Affiliation:
1. Division of Infectious Diseases, Institute of Primate Research, National Museums of Kenya, Karen, Nairobi, Kenya,1 and
2. Division of Geographic Medicine, School of Medicine, Case Western Reserve University, Cleveland, Ohio2
Abstract
ABSTRACT
Allergic-type immune responses, particularly immunoglobulin E (IgE), correlate with protective immunity in human schistosomiasis. To better understand the mechanisms of parasite elimination we examined the immune correlates of protection in baboons (
Papio cynocephalus anubis
), which are natural hosts for
Schistosoma mansoni
and also develop allergic-type immunity with infection. In one experiment, animals were exposed to a single infection (1,000 cercariae) or were exposed multiple times (100 cercariae per week for 10 weeks) and subsequently were cured with praziquantel prior to challenge with 1,000 cercariae. Singly and multiply infected animals mounted 59 and 80% reductions in worm burden, respectively (
P
< 0.01). In a second experiment, animals were inoculated with
S. mansoni
ova and recombinant human interleukin 12 (IL-12). This produced a 37 to 39% reduction in adult worm burden after challenge (
P
< 0.05). Parasite-specific IgG, IgE, IgM, and peripheral blood cytokine production were evaluated. The only immune correlate of protection in both experiments was levels of soluble adult worm antigen (SWAP)-specific IgE in serum at the time of challenge infection and/or 6 weeks later. Baboons repeatedly infected with cercariae or immunized with ova and IL-12 developed two- to sixfold-greater levels of SWAP-specific IgE in serum than did controls, and this correlated with reductions in worm burden (
r
2
, −0.40 to −0.64;
P
, <0.01). Thus, in baboons and unlike mice, adult worm-specific IgE is uniquely associated with acquired immunity to
S. mansoni
infection. This similar association of parasite-specific IgE and protection among primates infected with schistosomiasis, along with similar pathology, anatomy, and genetic make-up, indicates that baboons provide an excellent permissive experimental model for better understanding the mechanisms of innate and acquired immunity to schistosomiasis in humans.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference53 articles.
1. Antibody detection and preparation;Andrew S. M.;Current protocols in immunology,1992
2. IL-12, as an adjuvant, promotes a T helper 1 cell, but does not suppress a T helper 2 cell recall response;Bliss J.;J. Immunol.,1996
3. Immunization of mice and baboons with the recombinant Sm28GST affects both worm viability and fecundity after experimental infection with Schistosoma mansoni;Boulanger D.;Parasite Immunol.,1991
4. Butterworth A. E. 1987. Immunity in human schistosomiasis. Acta Trop. 12 (Suppl.):31–40.
5. Role of anaphylactic antibodies in immunity to schistosomes;Capron A.;Am. J. Trop. Med. Hyg.,1980
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