Experimental Angiostrongylus costaricensis infection in mice: immunoglobulin isotype responses and parasite-specific antigen recognition after primary low-dose infection

Abstract

Immunoglobulin isotype responses and parasite-specific antigen recognition were investigated in experimental Angiostrongylus costaricensis infection in two different mouse strains. Even in a low-dose infection with third-stage larvae (L3), BALB/c mice showed high mortality until 28 days postinfection (p.i.) in association with a low patency rate in surviving animals. On the other hand, low mortality and a high rate of patent infection was observed in C57BL/10 mice. Parasite-specific IgM, total IgG, and IgG subclasses against crude adult-worm antigen (AcAg) rose in both groups of mice from day 14 onward, with IgG and IgG1 being significantly elevated in BALB/c mice at 21 and 28 days p.i., respectively. For total IgE, significantly elevated concentrations were detected at 14 days p.i. in BALB/c mice as compared with C57BL/10 mice. A. costaricensis-specific antigen recognition by total IgG, IgG1, or IgG2a was similar in both mouse strains, intensifying from 3 to 4 weeks p.i., with recognition of immunodominant AcAg ranging between 80 and 210 kDa. This study provides evidence that in BALB/c and C57BL/10 mice, immunoglobulins, with the possible exception of IgE and IgG1, do not decisively contribute to the outcome of a primary A. costaricensis infection with respect to immunopathogenesis or parasite permissiveness.

Angiostrongylus costaricensis infection in C57BL/6 mice: MHC-II deficiency results in increased larval elimination but unaltered mortality

“…Soluble A. costaricensis adult worm antigen from fertile male and female worms was prepared as previously described (Geiger et al 1999). For the preparation of Ascaris lumbricoides antigen, one female worm was washed several times in PBS, cut into small pieces, transferred into a tissue grinder, and processed as described above.…”

“…In these mouse strains, striking differences in mortality were observed in the course of an A. costaricensis infection, and a genetic basis for resistance or susceptibility was proposed in which MHC genes may play an important role in the outcome of the infection (Ishii and Sano 1989;Ishih and Nishimura 1997). In previous experiments, the infection of C57BL/6 mice (haplotype H-2 b ) resulted in low mortality during prepatency and early patency (Ishii and Sano 1989;Geiger et al 1999). Whereas in C57BL/6 mice a mixed Th1-and Th2-type immune response was induced by mitogenic stimulation, in Balb/c mice, which show high mortality, a strong secretion of Th1-type cytokines was detected in the course of infection (Geiger et al 2001).…”

Intestinal granuloma formation in normal and SCID BALB/c mice infected with Angiostrongylus costaricensis

“…Previous experiments revealed mouse straindependent differences in susceptibility to A. costaricensis infections, suggesting a genetic predetermination for the different outcomes of infection (Ishii and Sano 1989;Ishih and Nishimura 1997). Geiger et al (1999) demonstrated no decisive contribution of immunoglobulins to mouse mortality in a primary A. costaricensis infection. In S. mansoni schistosomiasis, the formation of granulomas around eggs is the key pathogenic event in the liver, but granuloma formation also appears to benefit the host by protection against the direct toxic effect of the eggs (Amiri et al 1992).…”

“…According to the increasing possibility of human infection, due to the extension of the parasite's geographic distribution, this nematode has become increasingly important in medical and biological studies (Ishii and Sano 1989;Tungtrongchitr et al 1993;Geiger et al 1999;Ishih et al 2000). This nematode matures in mice experimentally, suggesting that the mouse is an alternative animal as a final host for experimental A. costaricensis infections (Ishii and Sano 1989), but little is known about the pathogenesis in mice infected with this nematode.…”

Ovos e órgãos reprodutores de fêmeas de Angiostrongylus costaricensis são reconhecidos mais intensamente por soros humanos de fase aguda na angiostrongilíase abdominal

“…Além dessas, foram usadas duas amostras oriundas de indivíduos portadores de outras parasitoses (CE = controle de especificidade): um paciente com diagnóstico de hidatidose e outro com sorologia positiva para toxocaríase. A amostra de soro de um indivíduo clinicamente sadio com reatividade muito baixa à pesquisa de anticor pos para angiostrongilíase por método imunoenzimático foi utilizada como controle normal (CN) 2 .…”