anti-HSV IgG Research Articles

DEFECTIVE ADHERENCE-MEDIATED POLYMORPHONUCLEAR LEUKOCYTE (PMN) ANTIBODY-DEPENDENT CELLULAR CYTOTOXICITY (ADCC) IN PATIENTS WITH PMN SURFACE GLYCOPROTEIN 138 (GP 138) DEFICIENCY

Four unrelated patients with GP 138 deficiency, marked leukocyte adherence defects, and normal IgG Fc receptors (PMN-EA rosettes = 84±6%) were studied for the ability to mediate PMN and Mononuclear cell (MC) ADCC and MC natural killer cytotoxicity (NKC) in a 51Cr assay to herpes simplex virus-infected Chang liver cells. At multiple effector to target cell ratios (E:T), patients' PMN-ADCC was absent (E:T 100:1, 4.3±1.2) and significantly lower than that of adults (27.9±8.1, p<.025), infants (15.3±4.2, p<.005) or cord blood (34.7±6.5, p<.001). Patients' MC-NKC (E:T 30:1, 10.0±4.3, controls 39.6±9.4, p<.05) and MC-ADCC (E:T 30:1, 27.6±11.4, controls 45.2±7.6) were markedly lower than controls but variable. A single cell agarose conjugation assay demonstrated that anti-HSV IgG increased the percentage of normal PMN conjugation (from 1.5±0.5 to 4.5±0.8, p<.01) but had no effect on conjugation of patients' PMN (1.2±0.2 to 1.0±0.2). Low MC cytotoxicity was due to lytic defects. This model demonstrates for the first time that PMN-ADCC is dependent on an adherence-mediating leukocyte surface glycoprotein GP138 to mediate target binding in addition to intact IgG Fc receptors. Supported by NIH grant HD 13021

Measurement of Antibody Against Human IgG by the Neutralization of IgG-Sensitized Herpes Simplex Virus

Abstract Antibody to human IgG was measured by its ability to neutralize herpes simplex virus (HSV) that had been sensitized with human anti-HSV IgG. Incubation of IgG-sensitized virus with anti-IgG showed that a linear relationship existed between the amount of virus neutralized and the concentration of anti-IgG. The reciprocal of the highest dilution of the anti-IgG serum that neutralized at least 50% of the IgG-sensitized virus was taken as the titer of the serum. The titer of the anti-IgG was affected by the concentration of anti-HSV IgG used to sensitize the virus, the concentration of sensitized virus and the amount of non-viral-bound human IgG in the fluid phase of the reaction mixture. The measurement of anti-IgG by the neutralization of sensitized virus was shown to be as sensitive and possibly more sensitive than the measurement of anti-IgG by the hemagglutination technique.