The Antibodies Involved in the Human Immune Response to Leptospiral Infection

Immunogenicity of boiled compared with formalized leptospiral vaccines in rabbits, hamsters and humans

“…However, serum of subject 1 from day 17 had a hamster protective titre of 2 and serum from day 31 had a hamster protective titre of 1. These protective titres are consistent with the MAT titres of the sera, in view of the results obtained in passive protection experiments with human sera (Adler & Faine, 1978a). Thus the failure of sera of subjects 2 and 3 to protect was due to low protective titres correlated with their low MAT titres.…”

“…A possible criticism may be that IgG antibodies were not detected by agglutination tests because IgG is not as good an agglutinator as IgM. However, in an analogous situation IgG agglutinins were readily detectable in humans with naturally acquired leptospiral infection (Adler & Faine, 1978a).…”

“…The pomona vaccinees did not produce any detectable antibody up to 2 months after immunization, while the two who received serovar patoc BLV produced low titres of agglutinins and also antibodies to erythrocyte-sensitizing F4 antigen of serovar patoc (Fig. 3) (Adler & Faine, 1978a). Fractionation of their sera on sucrose density gradients showed that the reacting antibody in both tests was detected solely in the IgM-containing fractions.…”

“…The microscopic agglutination test (MAT) and hamster protection test were performed as described previously, as was the method for fractionating sera on sucrose density gradients (Adler & Faine, 1978a).…”

“…They were bled from the marginal ear vein. Hamsters were infected with leptospires of serovar pomona as described previously (Adler & Faine, 1978a). Dermal toxicity tests in guinea-pigs Adult albino guinea-pigs were injected ID in their shaved backs with 0-1 ml of the test material.…”