It has been suggested that the effects of specific serum therapy in type I lobar pneumonia are due, not to the specific antibodies contained in the serum, but to the nonspecific action of the intravenously administered horse serum proteins. Miller1 and von den Velden,2 as well as Hallermann and Kähler,3 have made this suggestion because of the symptomatic changes they noted in lobar pneumonia following the injection of protein materials other than immune horse serum, such as typhoid vaccine, normal horse serum and normal human serum. Sonnenfeld4 and Lichtenstein5 have supported this suggestion because they occasionally observed striking clinical improvement in patients with pneumonia due to pneumococci other than type I following the administration of serum that presumably contained only type I pneumococcic antibodies.
An examination of the question from the point of view of those who have had extended experience with the specific serum,
SUTLIFF WD, FINLAND M, HUNNICUTT TN. DIRECT COMPARISON BETWEEN SPECIFIC AND NONSPECIFIC SERUM THERAPY FOR TYPE I LOBAR PNEUMONIA. Arch Intern Med (Chic). 1933;51(3):435-446. doi:10.1001/archinte.1933.00150220110008