The Specific Protective Property of Serum from Rats Infected with Cysticercus Crassicollis

[摘要] The foregoing results demonstrate that the formation of humoral protective antibodies in rats infected with C. crassicollis tends to parallel the degree of infection within the described experimental range. This parallelism, so evident during the first two weeks of infection, is soon lost, and after 28 days the serums have approximately the same protective value regardless of the degree of infection responsible for antibody formation.While ascertaining protective titers based upon minimal amounts of serum required to protect a normal animal, it was found that as the “end-point” was approached for 28-day serums, a marked increase in the destruction of larvae after encystment occurred. No such reaction was observed with serum taken approximately two weeks after infection. These results indicate the presence of two antibody mechanisms, one which destroys the larvae before encystment (“early immunity”) and another which causes the destruction of larvae after encystment (“late immunity”). The two effects can hardly be explained by a dilution of only one antibody since the late destruction was not obtained with immune serum taken two weeks after infection.

[学科分类] 生物科学（综合）