Antibody response to Syphacia obvelata infection was observed in AKR/J
mice by ELISA. Experimental infection with the pinworm eggs showed th
e presence of specific IgG against S. obvelata somatic antigens at 12
days postinfection, and that it increased steadily thereafter. Sera of
S. obvelata-infected mice showed cross-reactivity with somatic antige
ns of other Syphacia species such as S. mesocriceti and S. muris, but
not with Aspiculuris asiatica. Western blotting of S. obvelata antigen
with sera of S. obvelata-infected mice showed a corresponding increas
e in the number of bands during the course of infection. Infected mice
showed significantly higher antibody production to sheep red blood ce
lls than the uninfected control mice. Thus, S. obvelata infection is s
hown to alter the humoral response to nonparasitic antigenic stimuli.
These observations indicate that infection by helminths, which apparen
tly do not produce clinical symptoms, might modulate the immune system
of the host and, therefore, affect experimental results.