To examine supernatants (SNs) of human squamous cell carcinoma of the head and neck cell lines for soluble tumor-derived factors capable of inducing activation and proliferation of human immune cells.
The SN of squamous cell carcinoma of the head and neck cell line PCI-50 was cultured in serum-free medium and tested for the ability to induce expression of activation antigens, proliferation, cytotoxicity against tumor cell targets and cytokine production by purified human natural killer (NK) and CD4+ T cells.
Supernatant of PCI-50 promoted expression of the following activation markers on NK and T cells: CD25 (interleukin-2R-α), HLA-DR (major histocompatibility complex class II), CD54 (ICAM-1), CD71 (transferrin receptor), and CD69 (activation-inducing molecule). In addition, SN induced and significantly sustained (P<.01) proliferation of human unseparated peripheral blood lymphocytes and NK or T cells in culture. Purified human NK or T cells cultured in the presence of the SN and IL-2 (120 IU/mL) had significantly higher antitumor cytotoxicity than that mediated by NK or T cells cultured in AIM-V medium and IL-2. The SN induced cytokine (interferon γ, tumor necrosis factor a, interleukin-6) production in purified NK or T cells. When the SN was fractionated by molecular weight-based filtration into fractions greater and less than 30 kd, the growth- and cytotoxicitypromoting activities were consistently detectable in the greater than 30-kd fraction.
Culture SN of squamous cell carcinoma of the head and neck cell lines contain a soluble factor(s) capable of activating NK and CD4+ T cells and of promoting growth and antitumor cytotoxicity of these lymphocyte subsets in vitro.(Arch Otolaryngol Head Neck Surg. 1995;121:285-292)
Hirabayashi H, Yasumura S, Lin W, Amoscato A, Johnson JT, Herberman RB, Whiteside TL. Production by Human Squamous Cell Carcinoma of a Factor Inducing Activation and Proliferation of Immune Cells. Arch Otolaryngol Head Neck Surg. 1995;121(3):285-292. doi:10.1001/archotol.1995.01890030025005