Decreases in T-Cell Tumor Necrosis Factor α Binding With Interferon Beta Treatment in Patients With Multiple Sclerosis | Demyelinating Disorders | JAMA Neurology | JAMA Network
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Figure 1. 
Tumor necrosis factor α (TNF-α) bioassay results. A TNF-dependent cell lytic assay was performed with mouse L-929 fibroblasts used as the cell target. Cells exposed to culture medium alone are set at 0% lysis, and those exposed to 3-mol/L guanidine hydrochloride provide the end point of 100% lysis.

Tumor necrosis factor α (TNF-α) bioassay results. A TNF-dependent cell lytic assay was performed with mouse L-929 fibroblasts used as the cell target.31 Cells exposed to culture medium alone are set at 0% lysis, and those exposed to 3-mol/L guanidine hydrochloride provide the end point of 100% lysis.

Figure 2. 
Left, Competitive binding of radiolabeled and unlabeled tumor necrosis factor α (TNF-α) to T cells. T cells were incubated with iodine 125–labeled TNF-α (0.5 ng) and the indicated amounts of unlabeled TNF-α. The binding of radiolabeled TNF-α is expressed as a percentage of the binding in the absence of the unlabeled ligand. Right, Competitive binding analyzed according to the Scatchard method.

Left, Competitive binding of radiolabeled and unlabeled tumor necrosis factor α (TNF-α) to T cells. T cells were incubated with iodine 125–labeled TNF-α (0.5 ng) and the indicated amounts of unlabeled TNF-α. The binding of radiolabeled TNF-α is expressed as a percentage of the binding in the absence of the unlabeled ligand. Right, Competitive binding analyzed according to the Scatchard method.

Figure 3. 
Maximal receptor numbers of binding of iodine 125–labeled tumor necrosis factor α to T cells in patients with multiple sclerosis (MS) (before and 3 and 6 months after initiating treatment with interferon beta-1b) and age-matched healthy controls. Each point for controls represents the mean value of 3 assays (at the beginning and 3 and 6 months later). Horizontal lines indicate mean values.

Maximal receptor numbers of binding of iodine 125–labeled tumor necrosis factor α to T cells in patients with multiple sclerosis (MS) (before and 3 and 6 months after initiating treatment with interferon beta-1b) and age-matched healthy controls. Each point for controls represents the mean value of 3 assays (at the beginning and 3 and 6 months later). Horizontal lines indicate mean values.

Table 1. 
Clinical Features of Patients
Clinical Features of Patients
Table 2. 
T-Cell TNF-α Receptor Bmax Values in Patients With MS and Controls*
T-Cell TNF-α Receptor Bmax Values in Patients With MS and Controls*
Table 3. 
Peripheral-Blood Lymphocyte Subsets in Patients With MS and Controls*
Peripheral-Blood Lymphocyte Subsets in Patients With MS and Controls*
Original Contribution
January 1999

Decreases in T-Cell Tumor Necrosis Factor α Binding With Interferon Beta Treatment in Patients With Multiple Sclerosis

Author Affiliations

From the Section of Neurology, Department of Neurosciences, University of Pisa, Pisa (Drs Bongioanni, Mosti, Moscato, Lombardo, and Meucci), and Institute of Clinical Medicine, University of Turin, Turin (Dr Manildo), Italy.

Arch Neurol. 1999;56(1):71-78. doi:10.1001/archneur.56.1.71

Objective  To investigate the effects of interferon beta treatment on T-cell tumor necrosis factor α (TNF-α) binding (which is a possible marker for T-cell–dependent immune function) in patients with multiple sclerosis.

Design  The TNF-α binding on T lymphocytes from patients with stable relapsing-remitting multiple sclerosis was assayed before and 3 and 6 months after the start of treatment with interferon beta.

Setting  The study was performed on ambulatory patients in a tertiary care center.

Patients  Eighteen patients with clinically definite stable relapsing-remitting multiple sclerosis (13 women and 5 men; mean [± SD] age, 32.6±7.1 years) were selected consecutively. Clinical status was defined according to the Expanded Disability Status Scale. All patients were treated with 8×106U of interferon beta-1b subcutaneously every other day. Eighteen age- and sex-matched healthy subjects, with no family history of neuropsychiatric disorders, served as controls.

Results  T lymphocytes from untreated patients with multiple sclerosis had significantly more TNF-α receptors than those from controls (mean±SE, 837±33 vs 135±5 receptors per cell). After 3 months of treatment with interferon beta-1b, they showed a significant decrease (P<.001) in TNF-α binding (452±29 receptors per cell). After 6 months, T-cell TNF-α maximal receptor numbers were even lower (345±35 receptors per cell).

Conclusion  Given that increased TNF-α binding might be linked to lymphocyte activation, our data demonstrate that a major effect of interferon beta-1b treatment is to decrease T-cell activation.

MULTIPLE SCLEROSIS (MS) is characterized pathologically by areas of primary demyelination and perivascular inflammatory infiltrates of lymphocytes and macrophages. Immune-mediated factors, perhaps induced by viral infection, are likely to be implicated in the pathogenesis of MS.1,2 Cytokines are important central nervous system immunomodulators3; unbalanced immune responses in patients with MS may depend on a cytokine network derangement.

The cytokine tumor necrosis factor α (TNF-α) is a 17-kd protein, 157 amino acids long, produced primarily by macrophages but also by T and B lymphocytes, natural cytotoxic cells, astrocytes, and microglial cells, in response to a wide variety of stimuli.4,5 Besides its antitumoral activity, TNF-α is involved in inflammation, viral replication, and immune modulation.

Tumor necrosis factor α is linked to the inflammatory demyelinating process of MS and experimental autoimmune encephalomyelitis, an animal model for human MS. It has been identified immunohistochemically in the lesions of brains of patients with MS.6 It is able to induce the expression of major histocompatibility complex class II molecules on gliocytes7; antigen presentation by astrocytes positive for major histocompatibility complex may enhance the local immune response and, thus, facilitate continuous growth of lesions. Several authors have demonstrated a significant rise in TNF-α messenger RNA and production by blood mononuclear cells before onset of an acute exacerbation.8,9

Tumor necrosis factor α mediates its biological effects through binding to a single class of specific cell surface high-affinity receptors of 55- to 60-kd and 75- to 80-kd molecular size, referred to as p60 (type I) and p80 (type II). Increased concentrations of the former are measured in the serum of patients with MS.10,11 The p60 form of the TNF-α receptor contains 455 amino acid residues; the p80 form, 461 amino acids.12-14

Both receptor types bind TNF-α with equal affinity and transduce signals independent of each other. Receptor expression is regulated by a variety of agents, including cytokines (interferons, interleukin [IL] 1, IL-2, IL-4, IL-6, IL-8, and TNF-α), protein kinase activators, corticosteroids, and Ca++ ionophores.12 After TNF-α binds its receptor (either the p60 or the p80 form), the nuclear factor-κB–related transcriptional pathway is activated.

Since the early 1980s, interferons have been proposed for the treatment of MS, because of the evidence that an immunoregulatory derangement or a viral infection, or both, may have a pathogenetic role.15 Interferon gamma, however, has been proved to activate MS,16 and no effect was observed when interferon beta was given intravenously.17 On the contrary, intrathecally administered interferon beta has been reported to reduce the exacerbation rate in patients with relapsing-remitting MS,18 although with discordant results in other trials.19 Studies of parenterally administered human recombinant interferon beta in patients with relapsing-remitting MS showed fewer relapses20,21 and a significant reduction in the average number of gadolinium-enhancing lesions on magnetic resonance images in treated patients.21,22

In a pilot study, peripheral-blood monocytes from patients with MS who received interferon beta demonstrated decreased mitogen-driven IL-2 receptor (IL-2R) expression.23 Brod et al24,25 found, in patients with stable relapsing-remitting MS treated with interferon beta-1b, that after 3 months of treatment peripheral-blood mononuclear cells stimulated with concanavalin A secreted significantly more TNF-α, interferon (IFN) γ, IL-2, IL-6, and IL-10 and less IL-4 than concanavalin A–stimulated mononuclear cells before treatment.24 However, at 9 months, concanavalin A–induced TNF-α secretion decreased significantly below baseline, whereas IFN-γ secretion increased above baseline; there were no changes in concanavalin A–induced IL-2 and IL-10 secretion during the 9-month period or in IL-6 secretion during the 6-month period.25 Similar findings of no persistenteffects on inflammatory or counterregulatory anti-inflammatory cytokine synthesis also have been reported in other studies.26

The majority of patients with MS treated with interferon beta-1b show a decreased number of IFN-γ–producing blood lymphocytes,27,28 but there are also discordant findings in the literature.29

Costimulatory molecules help determine T-cell responses. CD80 (B7-1) and CD86 (B7-2), costimulatory proteins on antigen-presenting cells, bind to CD28 on T cells. During MS exacerbations, the number of circulating CD80+ B lymphocytes is significantly increased; therapy with interferon beta-1b markedly reduces the number of these cells and increases CD86+ monocyte number.30

Therapy with interferon beta-1b is associated with a remarkable increase in soluble vascular cell adhesion molecule 1, and this effect correlates with the resolution of contrast-enhancing lesions on magnetic resonance images31; moreover, patients with MS treated with interferon beta-1b show a reduced expression of vascular cell adhesion molecule 1 ligand, the very late antigen 4, on their lymphocytes.32

We studied T-cell TNF-α binding in untreated patients with MS.33 We found that lymphocytes from patients bear significantly more receptors than those from healthy controls; among patients with MS, subjects in relapse showed higher T-cell TNF-α binding than those in stable phase. In the present work, we assayed TNF-α receptor binding on T lymphocytes from patients with relapsing-remitting MS treated with human recombinant interferon beta-1b, to study the effects of interferon beta-1b on T-cell activation in vivo.

Subjects and methods

Eighteen patients with clinically definite stable relapsing-remitting MS34 were consecutively enrolled at the Section of Neurology, Department of Neurosciences, University of Pisa, Pisa, Italy. Relapsing-remitting MS was characterized by clearly defined acute attacks with full recovery or with sequelae and residual deficit on recovery.35 Clinical status was defined according to Kurtzke's36 criteria (Expanded Disability Status Scale). There were 5 men and 13 women, aged 24 to 46 years (mean±SD, 32.6±7.1 years). Ages at onset ranged from 16 to 41 years; disease duration, 1 to 11 years; and Kurtzke Expanded Disability Status Scale scores, 1 to 3.5 (Table 1).

T-cell TNF-α binding was measured in all patients before the initiation of alternate-day subcutaneous treatment with 8×106U of interferon beta-1b37 and after 3 and 6 months during therapy. Serum IL-2 and soluble IL-2R levels were used as markers for circulating activated T cells38; for IL-2 and soluble IL-2R immunoenzymatic assays, commercial kits were purchased (Genzyme, Milan, Italy).

Patients were monitored for side effects during the 6-month period, including systemic symptoms, local injection-site reaction, and changes in peripheral total leukocyte count and lymphocyte count.

At the time of the first observation and blood sampling, none of the patients had received corticosteroids for at least 1 month, or immunosuppressive drugs for at least 6 months; during interferon beta-1b treatment, none of them received corticosteroids or immunosuppressive medications. No subject showed any symptoms or signs of concurrent infection either before or during interferon beta-1b therapy.

The control population consisted of 18 age- and sex-matched healthy subjects selected among blood donors or laboratory personnel, aged 18 to 51 years (mean±SD, 31.7±9.6 years).

T-cell TNF-α binding was also assayed in 10 patients with rheumatoid arthritis (mean±SD age, 53.7±15.8 years), and in newly diagnosed neurologic patients suffering from myasthenia gravis (n=8; mean±SD age, 41.8±16.8 years), idiopathic Parkinson disease (n=7; mean±SD age, 68.4±17.6 years), and dementia of the Alzheimer type (n=10; mean±SD age, 72.3±14.4 years), as disease controls.

Patients and controls gave their informed consent before their inclusion in the study.

Separation of t cells from peripheral blood

All subjects underwent venipunture between 7 and 8 AM to avoid circadian variations of lymphocyte subsets.39 Patient and control samples were processed together in the same way, providing sex- and age-matched controls for patients with MS.

After mixing with an equal volume of Ca++- and Mg++-free Hanks balanced saline solution (Sigma-Aldrich, Milan, Italy), blood was centrifuged with Ficoll-Paque (Amersham Pharmacia Biotech Italia, Milan) at 400g for 30 minutes at room temperature. Buffy coats of mononuclear cells, carefully transferred with sterile pipettes into centrifuge tubes, were spun at 800g for 10 minutes at 4°C to obtain cell pellets. After cell counting with a Neubauer hemocytometer, lymphocytes and monocytes in Dulbecco modified minimal Eagle medium (Sigma-Aldrich) with 10% fetal calf serum (Bio-Whittaker International PBI, Milan) were plated overnight in plastic Petri dishes at 4°C to separate peripheral-blood lymphocytes from macrophages that adhere to the floor of Petri dishes. To obtain pure T cells, lymphocytes were incubated in Dulbecco modified minimal Eagle medium with 10% fetal calf serum at 4°C for 2 hours in petri dishes coated with mouse anti–human IgG (Sigma-Aldrich).

Such a panning procedure was repeated thrice, so that we obtained 98% pure T-cell suspensions; T lymphocytes were identified morphologically and as CD3+ cells by flow cytometry.

Radioiodination of Human TNF-α

Recombinant human TNF-α was purchased (Sigma-Aldrich; specific activity, 2×107 U/mg of protein). Fifty micrograms of concentrated TNF-α was reacted for 12 hours on ice with 37 MBq of Bolton-Hunter reagent labeled with iodine 125 (125I) (DuPont de Nemours, Milan) in 0.1 mL of 50-mmol/L sodium phosphate buffer (pH 7.4) with 5% sucrose.

The reaction was quenched with 0.2-mol/L glycine (Sigma-Aldrich) in 50-mmol/L sodium phosphate buffer (pH 7.4). Unconjugated iodine was separated from conjugated iodine over a fine column (Sephadex G-25, Amersham Pharmacia Biotech) equilibrated with 50-mmol/L sodium phosphate buffer (pH 7.2) containing 5% sucrose (Sigma-Aldrich), 1-mmol/L dithiothreitol (Sigma-Aldrich), and 1-mg/mL gelatin (Sigma-Aldrich). The 125I–TNF-α eluted from the gel column as a monomer with a molecular weight of 17 kd. The peak fractions containing 125I–TNF-α were pooled and stored at −70°C in 20-µL samples. The 125I–TNF-α was biologically active, as shown by the cytotoxicity assay on mouse L-929 fibroblast cells,40 where TNF-α and 125I–TNF-α are equipotent (Figure 1). The initial specific activity of the 125I–TNF-α of different preparations ranged between 0.37 and 0.74 MBq/µg, defined as bindable counts per minute per microgram of biologically active TNF-α.40

125I–TNF-α Binding

Before use in binding assays, 125I–TNF-α was diluted in 50-mmol/L sodium phosphate buffer (pH 7.2), 5% sucrose, 1-mmol/L dithiothreitol, and 1-mg/mL bovine serum albumin (Sigma-Aldrich); each dilution was centrifuged for 5 minutes at 15,000g at 4°C. In standard binding assays, 2×106 T cells from each subject were incubated in duplicate at 4°C in 750 µL of Dulbecco modified minimal Eagle medium with Hepes buffer (10 mmol/L, pH 7.2) and 10% fetal calf serum for 2 hours with different amounts of 125I–TNF-α (from 0.1 to 0.5 ng). In competitive binding experiments, increasing amounts of unlabeled TNF-α were added to standard binding assays.

Nonspecific binding was determined by adding in duplicate a 100-fold excess of unlabeled TNF-α; at this point, the addition of greater amounts of unlabeled TNF-α did not further reduce the binding of 125I–TNF-α. At the end of incubation, samples were layered over 300 µL of a di-n-butylphthalate and dinonylphthalate mixture (Sigma-Aldrich) in microfuge tubes and spun for 4 minutes at 15,000g at 4°C.

Supernatants (containing free 125I–TNF-α) were discarded, and cell pellet radioactivity was counted in a gamma counter (Beckman Italia, Milan) with 55% efficiency. A blank reaction, without cells, bound less than 50 counts per minute over the machine background: such a blank was subtracted from all bound counts per minute reported. Final results about binding variables were achieved through the Scatchard equation, using McPherson's41 LIGAND program, which determines the maximal receptor number (Bmax) and the dissociation constant (Kd).

Peripheral-Blood Lymphocyte Treatment With Anti–TNF-α Receptor Antibodies

To identify the receptor type, in a subset of patients' and controls' samples (n=10 each), we preincubated T lymphocytes (2×106 cells) with 2 anti–TNF-α receptor monoclonal antibodies42 for 1 hour at 4°C.

In group 1, we used an anti-p60 antibody (htr-9), at a concentration of 15 µg/mL; in group 2, an anti-p80 antibody (utr-1), at 15 µg/mL; in group 3, both antibodies; and in group 4, none (only preimmune serum). Afterward, we assayed TNF-α binding as above.

Flow cytometry

In a limited set of patients (n=10) and controls (n=10), peripheral blood (3 mL per subject) was collected in EDTA test tubes. White blood cell count and leukocyte differentiation were performed routinely by means of an automated cell counter (Coulter Electronics Ltd, Luton, England) and May-Grünwald Giemsa staining.

One hundred microliters of blood was incubated at room temperature in the dark for 30 minutes with 10 µL of fluorescein isothiocyanate, phycoerythrin, or Quantum Red conjugated monoclonal antibodies against the following antigens: CD4, CD8, CD25 (IL-2Rα), CD120a (p60TNF-α receptor), and CD120b (p80TNF-α receptor).

With triple labeling technique, CD4+p60+IL-2R+, CD4+p80+IL-2R+, CD8+p60+IL-2R+, and CD8+p80+IL-2R+ cell subsets were assayed. The erythrocytes were lysed with a solution containing formic acid (0.1%), and the cells were stabilized and fixed by successive passages in sodium carbonate (50 mmol/L), sodium chloride (250 mmol/L), sodium sulfate (220 mmol/L), and paraformaldehyde (330 mmol/L). Then the samples were counted through a flow cytometer (Epics XL-MCL; Coulter Electronics Ltd) equipped with single 15-mW argon ion laser (excitation wavelength of 488 nm in combination with 530-nm, 575-nm, and 670-nm bandpass filters for fluorescein isothiocyanate, phycoerythrin, and Quantum Red, respectively).

Fluorescein isothiocyanate–conjugated mouse IgG1, phycoerythrin-conjugated mouse IgG1, and conjugated monoclonal antibodies–conjugated mouse IgG1 were used to evaluate nonspecific fluorescence (always less than 0.1%). As autofluorescence control, 10 µL of diluent (0.01-mol/L phosphate buffered saline, pH 7.4, containing 1% bovine serum albumin and 0.1% sodium azide) instead of 10 µL of fluorochrome-conjugated monoclonal antibodies was added to whole blood in test tubes. To exclude monocytes, other leukocytes, and debris, gates were selected on lymphoid cells, as determined by forward and right-angle scatter.

Data were recorded on xyz plots, with antibody-linked fluorescence intensity (in log unit) reported on each axis, ie, anti-CD4, anti-p60 (or alternatively anti-p80), and anti–IL-2R antibody fluorescence values for CD4+CD25+CD120a+ (or CD4+CD25+CD120b+) cells, and anti-CD8, anti-p60 (or anti-p80), and anti–IL-2R antibody fluorescence values for CD8+CD25+CD120a+ (or CD8+CD25+CD120b+) cells. Results were expressed as percentages of each subset to total lymphocytes, and as arbitrary units for fluorescence intensity. All analyses were performed without knowledge of the clinical diagnosis.

Statistical analysis

Statistical evaluation was performed by analysis of variance, with the SigmaStat software package (SigmaPlot 5.0; Jandel Scientific GmbH, Erkrath, Germany). A value of P<.05 was accepted as significant.


Human T cells from patients with MS and healthy controls constitutively expressed high-affinity TNF-α receptors. The binding of 125I–TNF-α was specific, since it was inhibited only by unlabeled TNF-α, whereas IFN-α, IFN-β, and IFN-γ were ineffective at inhibiting TNF-α binding.

Figure 2 shows a representative experiment of competitive binding of 125I–TNF-α and unlabeled TNF-α to T cells. Highly enriched T-cell suspensions were incubated with 500 pg of 125I–TNF-α and different amounts of unlabeled TNF-α: a 100-fold excess of unlabeled TNF-α was able to prevent greater than 80% of the 125I–TNF-α binding on T cells (Figure 2, left). Scatchard analysis of the data produced a linear plot (Figure 2, right) suggestive of a single-binding-site model. Saturation binding experiments gave similar results.

No significant differences in Kd values were found among patients with MS, rheumatoid arthritis, myasthenia gravis, Parkinson disease, and dementia of the Alzheimer type, and healthy controls (mean±SE, 67.9±4.4, 70.2±4.9, 67.2±3.8, 66.7±5.6, 67.5±4.7, and 69.1±4.7 pmol/L, respectively), or among pretreatment and treatment groups. However, highly significant (P<.001) differences in Bmax values were observed between patients with MS and controls: 837±33 vs 135±5 (mean±SE) receptors per cell (Figure 3). Significant differences in T-cell TNF-α binding also were observed between patients with MS and subjects with rheumatoid arthritis (756±34 receptors per cell; P=.04), and among patients with MS and subjects with myasthenia gravis, Parkinson disease, and dementia of the Alzheimer type (663±20, 633±28, and 701±22 receptors per cell, respectively; P<.001 for all).

Interferon beta-1b therapy caused a decrease in T-cell TNF-α receptor number; Bmax values were significantly (P<.001) lower 3 months after initiation of treatment (452±29 receptors per cell). At 6 months, Bmax values significantly decreased further (345±35 receptors per cell). In any case, however, TNF-α binding values in patients with MS remained significantly (P<.001) higher than those of controls.

Linear regression analysis performed in patients with MS (both pretreatment and treatment groups) resulted in no significant correlations between TNF-α receptor Bmax values and serum IL-2 levels (or soluble IL-2R levels).

In a subset of patients and controls (n=10), we found that anti-p60 antibody reduced T-cell TNF-α receptor Bmax values by 39% and 37% in patients and controls, respectively, whereas with anti-p80 antibody treatment, TNF-α receptor binding decreased by 56% in patients with MS and 58% in healthy controls (Table 2). Therefore, in both subject groups, p60 and p80 forms were approximately 40% and 60% of total T-lymphocyte TNF-α receptors, respectively. No significant differences were observed in the relative percentages, nor in the Kdvalues of both TNF-α receptor forms, between patients and controls (data not shown).

Three-color fluorescence analysis showed that the proportions of CD4+CD25+CD120a+, CD4+CD25+CD120b+, CD8+CD25+CD120a+, and CD8+CD25+CD120b+ cells did not significantly differ in patients and controls, ranging from 0.010 to 0.040. In both subject groups, similar proportions of cells expressed the p60 and the p80 forms of TNF-α receptors: 0.410±0.130 and 0.590±0.100, respectively, in patients and 0.440±0.170 and 0.610±0.190, respectively, in controls (Table 3). By overlaying histograms from patients and healthy controls and comparing them by means of nonparametric statistics, we found that in MS TNF-α binding is significantly (P<.001) up-regulated in both CD4+ and CD8+ cells. There were no significant differences in anti-p60 (or anti-p80) antibody fluorescence intensity in both patients and controls between CD4+CD120a+ and CD8+CD120a+ histograms, and between CD4+CD120b+ and CD8+CD120b+ histograms, respectively; this suggests similar TNF-α receptor expression in CD4+ and in CD8+ cells. As far as IL-2R is concerned, anti-CD25 antibody fluorescence intensity was significantly (P=.02) higher in patients with MS than in healthy controls.


In MS, disease-related immune changes are also found in peripheral-blood lymphocytes.33,43-53 Data from various laboratories suggest that the signals resulting from the binding of TNF-α to its receptor have a role in lymphocyte activation54-56; an enhanced number of high-affinity TNF-α receptors on activated T cells with respect to resting T lymphocytes has been reported in studies on TNF-α receptor expression in vitro modulation.57,58

We found previously33 that untreated patients with MS have significantly more T-cell TNF-α receptors than healthy controls do. In the present work, we confirmed such findings and demonstrated that both p60 and p80 TNF-α receptor forms are up-regulated in patients with MS, with the same ratio (2:3) as in controls.42

In the present study, moreover, we found that systemic treatment with interferon beta-1b is able to cause a decrease in T-lymphocyte TNF-α binding, in proportion to the duration of therapy. In separate in vitro experiments with T lymphocytes from normal subjects, we observed a decreased expression of high-affinity TNF-α receptors (Kd, 71.2±4.2 pmol/L) on concanavalin A–stimulated T cells treated with interferon beta-1b (500 U/mL), as compared with untreated control T lymphocytes activated with concanavalin A (5 ng/mL): 674±26 vs 1228±39 receptors per cell. Similar results were found in T-cell subsets: interferon beta-1b in vitro down-regulated TNF-α binding on concanavalin A–activated CD4+ and CD8+ T cells from normal donors, causing a significant (P<.001) decrease in TNF-α receptor Bmax from 1187±33 to 662±31 receptors per cell and from 1243±44 to 707±29 receptors per cell in CD4+ and CD8+, respectively. Such findings in vitro parallel our results in vivo: it is likely that interferon beta-1b counteracts T-cell activation.

Given the immunopathogenesis of MS (namely, the activation of peripheral T cells that, after having traversed the blood-brain barrier interacting with endothelial cells, encounter target self-antigens presented by perivascular macrophages and microglia), lymphocytes, monocytes and macrophages, blood-brain barrier endothelia, and microglia emerge as main targets for the action of interferon beta.59

Studies on microglia and astrocytes have shown complex findings. No inhibition by interferon beta on HLA-DR up-regulation by IFN-γ was found in adult human microglia,60 and the reported antagonism of interferon beta on the IFN-γ–mediated major histocompatibility complex class II molecule expression on cultured human astrocytes and an astrocytoma cell line61,62 has not been observed in studies on fetal astrocytes.60 However, Satoh et al63 demonstrated a counteracting effect of interferon beta on IFN-γ–mediated proliferation of human astrocytes in vitro. Moreover, interferon beta inhibits the ability of IFN-γ–primed rodent microglia and human macrophages to mount a respiratory burst59,64; by contrast, interferon beta up-regulates microglial and macrophage FcR expression approximately 3- to 4-fold,59 an effect implying enhanced phagocytosis. Microglia produce nitric oxide in response to both IFN-β and IFN-γ alone,65 and each synergizes with the other and with TNF-α.59 Pretreatment of astrocytes with interferon beta impairs IFN-γ induction of nitric oxide synthase.66 Interferon β increases TNF-α secretion by tissue macrophages and stimulated microglia, and no antagonism between interferon beta and IFN-γ has been reported.59

Interferon β inhibits IFN-γ–mediated up-regulation of major histocompatibility complex class II molecules on endothelial cells,67 therefore decreasing lymphocyte adhesion, since class II molecules might act as lymphocyte adhesion receptors on endothelium.68 Interferon beta-1a selectively down-regulates endothelial basal levels of the adhesion molecule very late antigen 4 and inhibits its up-regulation by interferon gamma.69

In patients with MS, very late antigen 4 (and very late antigen 5) expression is significantly higher on cerebrospinal fluid lymphocytes and reduced on peripheral T cells compared with normal controls, suggesting that this adhesion molecule is instrumental in selective lymphocyte recruitment in MS.32,70 Recently, discordant findings of no down-regulation by interferon beta-1a on the inducible expression of intercellular adhesion molecule 1, vascular adhesion molecule, or E-selectin have been reported.71

In vitro studies demonstrate interferon beta–mediated inhibition of T-cell receptor–dependent and independent proliferation of both CD4+ and CD8+ T cells.23,72-74 Interferon beta partially suppresses both antigen- and IL-2–driven proliferation of myelin basic protein–specific T-cell clones from patients with MS that are secreting helper T (TH) 1 cytokines.75 The mechanisms of interferon beta–mediated inhibition of T-cell proliferation are not clear so far. Down-regulation of IL-2R-α chain expression might be responsible, indirectly supported by elevated IL-2 levels in culture supernatants because of reduced consumption. It seems that at least a proportion of T cells fail to express high-affinity IL-2R in the presence of IFN-β.23,72,73,75 Moreover, several IFN-β inhibitory effects on T cells may be caused by indirect rather than direct effects. In this regard, the observation of IL-10 induction by interferon beta could be important,73,76 since IL-10, which is a mainly inhibitory cytokine suppressing the production of proinflammatory TH1 cells and favoring a TH2 (regulatory) environment, may directly inhibit T-cell proliferation and IL-2 production.77

In addition, interferon beta impairs other aspects of T-cell activation, namely up-regulation of IL-2R, transferrin receptors, CD2 expression, and the production of IFN-γ and TNF-α.23,72,74,75,78,79 Migration of activated T cells through the blood-brain barrier also depends on the ability of lymphocytes to cleave the component of the basement membrane surrounding cerebral endothelium.

Interferon beta-1b markedly decreases in vitro the activity of T-cell matrix metalloproteinases 2 (gelatinase A) and 9 (gelatinase B), lymphocyte enzymes that degrade subendothelial basement membrane constituents, such as fibronectin.80,81 Thus, interferon beta might hinder the migration of T cells through intracerebral vessel walls, leading to disruption of the blood-brain barrier and recruitment of other inflammatory cells. In support of this notion, interferon beta was most efficient in reversing blood-brain barrier dysfunction in patients with MS, documented by gadolinium-enhanced magnetic resonance imaging.82

On human peripheral-blood monocytes, interferon beta exhibits contrasting effects on individual class II antigens: interferon beta inhibits IFN-γ induction of HLA-DQ but not that of HLA-DR or HLA-DP69; on the contrary, in some reports, interferon beta actually increases the expression of HLA-DR and HLA-DP.83,84 In vitro interferon beta induces IL-10 secretion by peripheral-blood monocytes from patients with MS85 and significantly improves the nonspecific suppressor activity of mitogen-treated peripheral-blood monocytes.86

Interferon γ and TNF-α, the main T-cell–derived proinflammatory cytokines, are present in active MS plaques and have been functionally implicated in the disease process6,7,87,88; interferon beta given to patients with MS acts on a background of endogenous IFN-γ and TNF-α production. In the active disease, antagonism between exogenously administered interferon beta and endogenous IFN-γ and TNF-α would impair the ability of microglia to mount a respiratory burst and also to up-regulate major histocompatibility complex class II expression, leading to impaired cytotoxic function, decreased recruitment of activated T cells into the central nervous system, and decreased propagation and maintenance of the TH-cell arm of the immune response. In addition, the direct antiproliferative effect of IFN-β on T cells and on secretion of regulatory cytokines, such as IL-10, would help maintain the anti-inflammatory environment.

A decrease in the number of T-cell TNF-α receptors dependent on interferon beta-1b treatment might be caused, at least in part, by the antagonistic action of interferon beta-1b on TNF-α, and IFN-γ, which is able to up-regulate TNF-α receptors.89

Accepted for publication April 24, 1998.

Reprints: Paolo Bongioanni, MD, PhD, Department of Neurosciences, University of Pisa, Via Roma 67, 56100 Pisa, Italy (e-mail:

O'Gorman  MOger  J Cell-mediated immune functions in multiple sclerosis.  Pathol Immunopathol Res. 1987;6241- 272Google ScholarCrossref
Hartung  H-P Neurological progress: immune-mediated demyelination.  Ann Neurol. 1993;33563- 567Google ScholarCrossref
Ransohoff  RMBenveniste  EN Cytokines and the CNS.  London, England CRC Press Inc1996;31- 102
Aggarwal  BB Tumor necrosis factor. Gutterman  JUAggarwal  BBeds. Human Cytokines Handbook for Basic and Clinical Researchers New York, NY Blackwell Scientific Publishers1992;270- 285Google Scholar
Nicola  NA Guidebook to Cytokines and Their Receptors.  Oxford, England Oxford University Press1994;162- 194
Raine  CS The Dale E. McFarlin Memorial Lecture: the immunology of the multiple sclerosis lesion.  Ann Neurol. 1994;36(suppl 4)S61- S72Google ScholarCrossref
Bongioanni  P Tumor necrosis factor induces class II major histocompatibility complex antigen expression on cultured rat type-1 astrocytes.  J Chemother. 1991;332- 34Google Scholar
Chofflon  MJuillard  CJuillard  PGauthier  GGrau  GE Tumor necrosis α production as a possible predictor of relapse in patients with multiple sclerosis.  Eur Cytokine Netw. 1992;3523- 531Google Scholar
Rieckmann  PAlbrecht  MKitze  B  et al.  Tumor necrosis factor-α messenger RNA expression in patients with relapsing-remitting multiple sclerosis is associated with disease activity.  Ann Neurol. 1995;3782- 88Google ScholarCrossref
Rieckmann  PMartin  SWeichselbraun  I  et al.  Serial analysis of circulating adhesion molecules and TNF receptor in serum from patients with multiple sclerosis: cICAM-1 is an indicator for relapse.  Neurology. 1994;442367- 2372Google ScholarCrossref
Hartung  H-PReiners  KArchelos  JJ  et al.  Circulating adhesion molecules and TNF receptor in MS: correlation with MRI.  Ann Neurol. 1995;37289- 297Google ScholarCrossref
Smith  RABaglioni  C Characterization of TNF receptors. Aggarwal  BBVilcek  Jeds. Tumor Necrosis Factor Structure, Function and Mechanism of Action New York, NY Marcel Dekker Inc1992;131- 148Google Scholar
Fuchs  PStrehl  SDworzak  MHimmler  AAmbros  PF Structure of the human TNF receptor 1(p60) gene (TNFR1) and localization to chromosome 12p13.  Genomics. 1992;13219- 224Google ScholarCrossref
Dembic  ZLoetscher  UGubler  U  et al.  Two human TNF receptors have similar extracellular, but distinct intracellular domain sequences.  Cytokine. 1990;2231- 237Google ScholarCrossref
Jacobs  LO'Malley  JFreeman  AMurawski  JEkes  R Intrathecal interferon in multiple sclerosis.  Arch Neurol. 1982;39609- 615Google ScholarCrossref
Panitch  HSHirsch  RLSchindler  JJohnson  KP Treatment of multiple sclerosis with gamma interferon: exacerbations associated wth activation of the immune system.  Neurology. 1987;371097- 1102Google ScholarCrossref
Huber  MBamborschke  SAssheuer  JHeiss  WD Intravenous natural beta interferon treatment of chronic exacerbating-remitting multiple sclerosis: clinical response and CSF/MRI findings.  J Neurol. 1988;235171- 173Google ScholarCrossref
Jacobs  LSalazar  AMHerndon  R  et al.  Multicenter double-blind study of effect of intrathecally administered natural human fibroblast interferon on exacerbations of multiple sclerosis.  Lancet. 1986;21411- 1414Google ScholarCrossref
Milanese  CSalmaggi  ALa Mantia  L  et al.  Double-blind study of intrathecal beta-interferon in multiple sclerosis: clinical and laboratory results.  J Neurol Neurosurg Psychiatry. 1990;53554- 557Google ScholarCrossref
IFNB MS Study Group, Interferon beta-1b is effective in relapsing-remitting multiple sclerosis, I: clinical results of a multicenter, randomized, double blind, placebo-controlled trial.  Neurology. 1993;43655- 661Google ScholarCrossref
Jacobs  LCookfair  DRudick  R  et al. and the MS Collaborative Research Group, Intramuscular interferon beta-1a for disease progression in relapsing multiple sclerosis.  Ann Neurol. 1996;39285- 294Google ScholarCrossref
IFNB MS Study Group, Interferon beta-1b is effective in relapsing-remitting multiple sclerosis, II: MRI analysis results of a multicenter, randomized, double blind, placebo-controlled trial.  Neurology. 1993;43662- 667Google ScholarCrossref
Rudick  RACarpenter  CSCookfair  DL  et al.  In vitro and in vivo inhibition of mitogen-driven T-cell activation by recombinant interferon-beta.  Neurology. 1993;432080- 2087Google ScholarCrossref
Brod  SAMarshall  GD  JrHenninger  EMSriram  SKhan  MWolinsky  JS Interferon-β1b treatment decreases tumor necrosis factor-α and increases interleukin-6 production in multiple sclerosis.  Neurology. 1996;461633- 1638Google ScholarCrossref
Brod  SANelson  LDKhan  MWolinsky  JS Interferon β1b treatment of relapsing multiple sclerosis has no effect on CD3-induced inflammatory or counterregulatory anti-inflammatory cytokine secretion ex vivo after nine months.  Int J Neurosci. 1997;90135- 144Google ScholarCrossref
Byskosh  PVReder  AT Interferon β1b effects on cytokine mRNA in peripheral mononuclear cells in multiple sclerosis.  Mult Scler. 1996;1262- 269Google Scholar
Petereit  HFBamborschke  SEsse  ADHeiss  WD Interferon gamma producing blood lymphocytes are decreased by inteferon beta therapy in patients with multiple sclerosis.  Mult Scler. 1997;3180- 183Google ScholarCrossref
Crucian  BDunne  PFriedman  HRagsdale  RPross  SWiden  R Detection of altered T helper 1 and T helper 2 cytokine production by peripheral blood mononuclear cells in patients with multiple sclerosis utilizing intracellular cytokine detection by flow cytometry and surface marker analysis.  Clin Diagn Lab Immunol. 1996;3411- 416Google Scholar
Dayal  ASJensen  MALledo  AArnason  BG Interferon-γ–secreting cells in multiple sclerosis patients treated with interferon β1b Neurology. 1995;452173- 2177Google ScholarCrossref
Genc  KDona  DLReder  AT Increased CD80+ B cells in active multiple sclerosis and reversal by interferon β1b therapy.  J Clin Invest. 1997;992664- 2671Google ScholarCrossref
Calabresi  PATranquill  LRDambrosia  JM  et al.  Increases in soluble VCAM-1 correlate with a decrease in MRI lesions in multiple sclerosis treated with interferon β1b Ann Neurol. 1997;41669- 674Google ScholarCrossref
Calabresi  PAPelfrey  CMTranquill  LRMaloni  HMcFarland  HF VLA-4 expression on peripheral blood lymphocytes is down-regulated after treatment of multiple sclerosis with interferon beta.  Neurology. 1997;491111- 1116Google ScholarCrossref
Bongioanni  PMeucci  G T-cell tumor necrosis factor-α receptor binding in patients with multiple sclerosis.  Neurology. 1997;48826- 831Google ScholarCrossref
Poser  CMPaty  DWScheinberg  L  et al.  New diagnostic criteria for multiple sclerosis: guidelines for research protocols.  Ann Neurol. 1983;13227- 231Google ScholarCrossref
Lublin  FDReingold  SC Defining the clinical course of multiple sclerosis: results of an international survey.  Neurology. 1996;46907- 911Google ScholarCrossref
Kurtzke  JF Rating neurologic impairment in multiple sclerosis: an expanded disability status scale (EDSS).  Neurology. 1983;331444- 1452Google ScholarCrossref
Quality Standards Committee, American Academy of Neurology, Practice advisory on selection of patients with multiple sclerosis for treatment with Betaseron.  Neurology. 1994;441537- 1540Google ScholarCrossref
Trotter  JLClifford  DBMcInnis  JE  et al.  Correlation of immunological studies and disease progression in chronic progressive multiple sclerosis.  Ann Neurol. 1989;25172- 178Google ScholarCrossref
Bertouch  JVRoberts-Thompson  PJBradley  J Diurnal variation of lymphocyte subsets identified by monoclonal antibodies.  BMJ. 1983;2861771- 1772Google ScholarCrossref
Aggarwal  BBKohr  WJ Human tumor necrosis factor.  Methods Enzymol. 1985;116450- 451Google Scholar
McPherson  GA Kinetic, EBDA, Ligand, Lowry: A Collection of Radioligand Binding Analysis Programs.  Amsterdam, the Netherlands Elsevier Science Ltd1985;
Brockhaus  MSchönfeld  HJSchläger  EJHunziger  WLesslauer  WLötscher  H Identification of two types of tumor necrosis factor receptors on human cell lines by monoclonal antibodies.  Proc Natl Acad Sci U S A. 1990;873127- 3131Google ScholarCrossref
Noronha  ARichman  DPArnason  BG Detection of in vivo stimulated cerebrospinal fluid lymphocytes by flow cytometry in patients with multiple sclerosis.  N Engl J Med. 1980;303713- 717Google ScholarCrossref
Golaz  JSteck  AMoretta  L Activated T lymphocytes in patients with multiple sclerosis.  Neurology. 1983;331371- 1373Google ScholarCrossref
Brinkman  CJNillesen  WMHommes  OR T-cell subpopulations in blood and cerebrospinal fluid of multiple sclerosis patients: effect of cyclophosphamide.  Clin Immunol Immunopathol. 1983;29341- 348Google ScholarCrossref
Hafler  DAFox  DAManning  ME  et al.  In vivo activated T lymphocytes in the peripheral blood and cerebrospinal fluid of patients with multiple sclerosis.  N Engl J Med. 1985;3121405- 1411Google ScholarCrossref
Selmaj  KPlater-Zyberk  CRockett  KA  et al.  Multiple sclerosis: increased expression of interleukin-2 receptors on lymphocytes.  Neurology. 1986;361392- 1395Google ScholarCrossref
Konttinen  YTBergroth  VKinnunen  ENordström  DKouri  T Activated T lymphocytes in patients with multiple sclerosis in clinical remission.  J Neurol Sci. 1987;81133- 139Google ScholarCrossref
Corrigan  EHutchinson  MFeighery  C Fluctuations in T helper subpopulations in relapsing-remitting multiple sclerosis.  Acta Neurol Scand. 1990;81443- 447Google ScholarCrossref
Ofosu-Appiah  WMokhtarian  FMiller  AGrob  D Characterization of in vivo-activated T cell clones from peripheral blood of multiple sclerosis patients.  Clin Immunol Immunopathol. 1991;5846- 55Google ScholarCrossref
Calopa  MBas  JMestre  MArbizu  TPeres  JBuendia  E T cell subsets in multiple sclerosis: a serial study.  Acta Neurol Scand. 1995;92361- 368Google ScholarCrossref
Bongioanni  PFioretti  CVanacore  R  et al.  Lymphocyte subsets in multiple sclerosis: a study with two-colour fluorescence analysis.  J Neurol Sci. 1996;13971- 77Google ScholarCrossref
Bongioanni  PLombardo  FFioretti  CMeucci  G T-lymphocyte immunointerferon receptors in patients with multiple sclerosis.  J Neurol. 1996;243605- 610Google ScholarCrossref
Scheurich  PThoma  BUcer  UPfizenmaier  K Immunoregulatory activity of recombinant human tumor necrosis factor (TNF)–α: induction of TNF receptors on human T cells and TNF-α–mediated enhancement of T-cell responses.  J Immunol. 1987;1381786- 1790Google Scholar
Ware  CFCrowe  PDVanarsdale  TL  et al.  Tumor necrosis factor (TNF) receptor expression in T lymphocytes: differential regulation of the type I TNF receptor during activation of resting and effector T cells.  J Immunol. 1991;1474229- 4238Google Scholar
Tartaglia  LAGoeddel  DVReynolds  C  et al.  Stimulation of human T-cell proliferation by specific activation of the 75-kDa tumor necrosis factor receptor.  J Immunol. 1993;1514637- 4641Google Scholar
Munker  RDi Persio  JKoeffler  HP Tumor necrosis factor: receptors on hematopoietic cells.  Blood. 1987;741730- 1734Google Scholar
Santis  AGCampanero  MRAlonso  JLSanchez-Madrid  F Regulation of tumor necrosis factor (TNF)–α synthesis and TNF receptors expression in T lymphocytes through the CD2 activation pathway.  Eur J Immunol. 1992;223155- 3160Google ScholarCrossref
Hall  GLWing  MGCompston  DAScolding  NJ Beta-interferon regulates the immunomodulatory activity of neonatal rodent microglia.  J Neuroimmunol. 1997;7211- 19Google ScholarCrossref
McLaurin  JAntel  JPYong  VW Immune and non-immune actions of interferon β1b on primary human neural cells.  Mult Scler. 1995;110- 19Google Scholar
Barna  BPChou  SMJacobs  BYen-Lieberman  BRansohoff  RM Interferon-β impairs induction of HLA-DR antigen expression in cultured adult human astrocytes.  J Neuroimmunol. 1989;2345- 53Google ScholarCrossref
Ransohoff  RMDevajyothi  CEstes  ML  et al.  Interferon-beta specifically inhibits interferon-gamma-induced class II major histocompatibility complex gene transcription in a human astrocytoma cell line.  J Neuroimmunol. 1991;33103- 112Google ScholarCrossref
Satoh  JPaty  DWKim  SU Counteracting effect of IFN-β on IFN-γ–induced proliferation of human astrocytes in culture.  Mult Scler. 1996;1279- 287Google Scholar
Garotta  GTalmadge  KWPink  JRDewald  BBaggiolini  M Functional antagonism between type I and type II interferons on human macrophages.  Biochem Biophys Res Commun. 1986;140948- 954Google ScholarCrossref
Deguchi  MInaba  KMuramatsu  S Counteracting effect on interferon-α and -β on interferon-γ–induced production of nitric oxide which is suppressive for antibody response.  Immunol Lett. 1995;45157- 162Google ScholarCrossref
Stewart  VCGiovannoni  GLand  JMMcDonald  WIClark  JBHeales  SJ Pretreatment of astrocytes with interferon-α/β impairs interferon-γ induction of nitric oxide synthase.  J Neurochem. 1997;682547- 2551Google ScholarCrossref
Huynh  HKOger  JDorovini-Zis  K Interferon-β downregulates interferon-γ-induced class II MHC molecule expression and morphological changes in primary cultures of human brain microvessel endothelial cells.  J Neuroimmunol. 1995;6063- 73Google ScholarCrossref
Goodall  CACurtis  ASLang  SC Modulation of adhesion of lymphocytes to murine brain endothelial cells in vitro: relation to class II major histocompatibility complex expression.  J Neuroimmunol. 1992;379- 22Google ScholarCrossref
Soilu-Hanninen  MSalmi  ASalonen  R Interferon-β downregulates expression of VLA-4 antigen and antagonizes interferon-γ–induced expression of HLA-DQ on human peripheral blood monocytes.  J Neuroimmunol. 1995;6099- 106Google ScholarCrossref
Svenningsson  AHansson  GKAndersen  OAndersson  RPatarroyo  MStemme  S Adhesion molecule expression on cerebrospinal fluid T lymphocytes: evidence for common recruitment mechanisms in multiple sclerosis, aseptic meningitis, and normal controls.  Ann Neurol. 1993;34155- 161Google ScholarCrossref
Jiang  HWilliams  GJDhib-Jalbut  S The effect of interferon β1b on cytokine-induced adhesion molecule expression.  Neurochem Int. 1997;30449- 453Google ScholarCrossref
Noronha  AToscas  AJensen  MA Interferon β decreases T-cell activation and interferon γ production in multiple sclerosis.  J Neuroimmunol. 1993;46145- 154Google ScholarCrossref
Rep  MHHintzen  RQPolman  CHvan Lier  RA Recombinant interferon-β blocks proliferation but enhances interleukin-10 secretion by activated human T-cells.  J Neuroimmunol. 1996;67111- 118Google ScholarCrossref
Milo  RPanitch  H Additive effects of copolymer-1 and interferon-β1b on the immune response to myelin basic protein.  J Neuroimmunol. 1995;61185- 193Google ScholarCrossref
Pette  MPette  DFMuraro  PAFarnon  EMartin  RMcFarland  HF Interferon-β interferes with the proliferation but not with the cytokine secretion of myelin basic protein–specific, T-helper type 1 lymphocytes.  Neurology. 1997;49385- 392Google ScholarCrossref
Rudick  RARansohoff  RMPeppler  RMedendrop Vander-Brug  SLehmann  PAlam  J Interferon beta induces interleukin-10 expression: relevance to multiple sclerosis.  Ann Neurol. 1996;40618- 627Google ScholarCrossref
Taga  KTosato  G IL-10 inhibits human T-cell proliferation and IL-2 production.  J Immunol. 1992;1481143- 1148Google Scholar
Noronha  AJensen  MAToscas  ASihag  S IFN-beta down-regulates tumor necrosis factor release.  Neurology. 1992;42(suppl 3)159- 160Google Scholar
Abu-khabar  KSArmstrong  JAHo  M Type I interferons (IFN-α and -β) suppress cytotoxin (tumor necrosis factor-α and lymphotoxin) production by mitogen-stimulated human peripheral blood mononuclear cells.  J Leukoc Biol. 1993;52165- 172Google Scholar
Stuve  ODooley  NPUhm  JH  et al.  Interferon beta-1b decreases the migration of T lymphocytes in vitro: effects on matrix metalloproteinase-9.  Ann Neurol. 1996;40853- 863Google ScholarCrossref
Leppert  DWaubant  EBurk  MROksenberg  JRHauser  SL Interferon beta-1b inhibits gelatinase secretion and in vitro migration of human T cells: a possible mechanism for treatment efficacy in multiple sclerosis.  Ann Neurol. 1996;40846- 852Google ScholarCrossref
Stone  LAFrank  JAAlbert  PS  et al.  The effect of interferon-beta on blood-brain barrier disruptions demonstrated by contrast-enhanced magnetic resonance imaging in relapsing-remitting multiple sclerosis.  Ann Neurol. 1995;37611- 619Google ScholarCrossref
Spear  GTPaulnock  DMJordan  RLMeltzer  DMMerritt  JABorden  EC Enhancement of monocyte class I and II histocompatibility antigen expression in man by in vivo beta-interferon.  Clin Exp Immunol. 1987;69107- 115Google Scholar
Goldstein  DSielaff  KMStorer  BE  et al.  Human biologic response modification by interferon in the absence of measurable serum concentrations: a comparative trial of subcutaneous and intravenous interferon-beta serine.  J Natl Cancer Inst. 1989;811061- 1068Google ScholarCrossref
Porrini  AMGambi  DReder  AT Interferon effects on interleukin-10 secretion: mononuclear cell response to interleukin-10 is normal in multiple sclerosis patients.  J Neuroimmunol. 1995;6127- 34Google ScholarCrossref
Noronha  AToscas  AJensen  MA Interferon beta augments suppressor cell function in multiple sclerosis.  Ann Neurol. 1990;27207- 210Google ScholarCrossref
Panitch  HSFolus  JSJohnson  KP Beta interferon prevents HLA class II antigen induction by gamma interferon in MS.  Neurology. 1989;39(suppl 1)171- 172Google Scholar
Storch  MLassmann  H Pathology and pathogenesis of demyelinating diseases.  Curr Opin Neurol. 1997;10186- 192Google ScholarCrossref
Aggarwal  BBEessalu  TEHass  PE Characterization of receptors for human tumor necrosis factor and their regulation by gamma-interferon.  Nature. 1985;318665- 667Google ScholarCrossref