Antibody detection and kinetics of antibody production during early stages of immunization with hepatitis B virus vaccine

Abstract

Antibodies to influenza virus and human immunodeficiency virus are detectable in B cells during the early stages of the immune response, prior to their occurrence in plasma. To investigate similar phenomena in a model of immunization against hepatitis B virus (HBV) infection, medical students in Ghana were screened for HBV markers, HBV surface (HBs) antigen (HBsAg), and HBV core antibodies (anti-HBc). Consenting volunteers, 24 of whom were seronegative (susceptible) and 2 of whom were positive for anti-HBc (prior infection), were vaccinated on day 0, day 40, and 6 months. Two sets of 10 blood samples, sequentially collected at intervals of 2 days following each immunization on days 0 and 40, were processed into B-cell lysates and plasma. Solid-phase HBsAg coated on microtiter plates for enzyme immunoassay or nitrocellulose membranes for dot blot assay was used to detect anti-HBs activity by an indirect antiglobulin assay. A commercially procured sandwich immunoassay was used, along with an enzyme-linked immunosorbent assay and a dot blot assay, for the detection of anti-HBs in B-cell lysates and plasma. Following the first injection of vaccine, a single sample of B-cell lysate collected between 5 and 21 days revealed anti-HBs in 18/21 subjects with no plasma antibodies detectable by sandwich immunoassay. After the booster dose was injected on day 40, a single sample of B-cell lysate collected between 44 and 49 days showed anti-HBs in 16/19 subjects, and this was accompanied by plasma antibodies in 8 subjects. In contrast, between 8 and 13 days, both subjects with prior HBV infection showed anti-HBs in B-cell lysates and plasma. Thus, primary immunization with the HBV vaccine appears to transiently elicit low-affinity anti-HBs in B-cell lysates into plasma.

FIG. 1.

Anti-HBs expressed as optical density/cutoff values in B-cell lysate and plasma samples from two susceptible volunteers (volunteers 3 and 5) and two volunteers with anti-HBc only (volunteers 25 and 26). (Top and middle panels) The anti-HBs in B-cell lysates is shown as solid lines and circles, and that in plasma is shown as dashed lines and open circles; (bottom panel) the anti-HBs in plasma is shown as a solid line and circles for volunteer 25 and as dashed lines and open circles for volunteer 26. In all cases the first HBV vaccine injection was at time zero and the first booster injection was at 40 days. The ordinate indicates the EIA S/CO.

FIG. 2.

Days of occurrence and level of anti-HBs reactivity in B-cell lysate and plasma samples after the primary and the first booster injections of recombinant HBV vaccine to 24 susceptible volunteers. First row, numbers of volunteer with B-cell lysate reactivity at different time intervals after either injection; second row, reactivity and timing of B-cell lysate reactivity after the first boost injection; third row, reactivity of antigen sandwich anti-HBs assay with plasma after the primary injection of the vaccine; fourth row, numbers of volunteers with plasma anti-HBs reactivity after the first booster injection of the vaccine.