Anisakis simplex: antigen recognition and antibody production in experimentally infected mice

Abstract

The kinetics of antibody response to intraperitoneal infection of mice with third stage larvae of Anisakis simplex was investigated by ELISA. Maximum antibody response to excretion-secretion (ES) antigens was reached before maximum response to somatic (SA) antigens. Total immunoglobulin (Ig) production (consisting mainly of IgM and IgG1 isotypes) was very similar in both cases. Immunoblotting was used to characterize the antigens recognized by the host in the presence or absence of the metabolic products released by the parasite in vivo. Sera from mice infected with live larvae (anti-L3 L serum) and immunized with dead larvae (anti-L3 D serum) recognized a similar pattern of bands in immunoblots of ES and SA antigen preparations. In the latter, however, three bands at 14, 17 and 18 kD were only recognized by the anti-L3 L serum. A possible explanation is that these low molecular weight antigens are ES products released only in vivo. Finally, the immune response in mouse was compared using ELISA and immunoblotting with the response of a human anisakiasis reference serum, and was found to display considerable similarities. This suggests that the mouse may be a useful model for studying the immunobiology of A. simplex in man.

Immune reactions and allergy in experimental anisakiasis

“…Specific rabbit IgM reached a peak 2 weeks after a primary infection, and then decreased (Quan et al, 1991). By way of contrast, the specific mouse IgM was elevated immediately after L3 infection, and continuously increased for 8 weeks (Iglesias et al, 1993).…”

“…Specific rabbit IgM reached a peak 2 weeks after a primary infection, and then decreased (Quan et al, 1991). By way of contrast, the specific mouse IgM was elevated immediately after L3 infection, and continuously increased for 8 weeks (Iglesias et al, 1993).In sera obtained from rats infected via peritoneal L3 inoculation, the levels of IgM specific for the L3 product were correlated with the numbers of infecting L3 (Amano et al, 1995). L3 product-specific IgM levels were elevated quickly after a primary infection, and then slowly from 4 weeks to 8 weeks PI.…”

“…No specific IgE was isolated after L3 inoculation into the peritoneum of mice (Iglesias et al, 1993). Baeza et al (2005) successfully induced L3-specific IgE via the immunization of mice with L3 worm crude extracts, using pertussis toxin and alum as adjuvants (Baeza et al., 2005).…”

“…This suggests that some other cell type may facilitate the production of specific IgE. Although the production of specific IgG 2a in mice was also observed after the inoculation of L3 into the peritoneum (Iglesias et al, 1993), the production of specific IgG 2a induced by the injection of L3 crude extracts was greater than that seen with specific IgG 1 , which indicates a Th1 response in the immune reaction greater than that associated with Th2. In addition, ESP tends to be preferred over crude larval extracts, as the detection of specific IgE against the ESP of A. simplex larvae has proven superior to that observed against crude extracts, and a high level of specific antibody production against small volumes of ESP has been observed in other nematode infections (Sugane and Oshima, 1983;Sugane et al, 1985; Cho, 2000).…”

Anisakis simplex: from Obscure Infectious Worm to Inducer of Immune Hypersensitivity

“…Several research groups have investigated the kinetics of specific antibody production in mice and rabbits (118,119,133,149), but these results cannot be directly extrapolated to allergic responses in humans. In 2006, Cho et al described the specific antibody response in rats that were infected orally with L3 on two occasions at intervals of 9 weeks.…”