Systemic release of mucosal mast cell protease during infection with the intestinal protozoal parasite, Eimeria nieschulzi. Studies in normal and nude rats

Abstract

The systemic secretion of rat mucosal mast cell protease (RMCPII), a major product of rat mucosal mast cells (MMC), was examined during primary infections with the protozoan parasite, Eimeria nieschulzi in CFH/B, athymic (rnu/rnu) and euthymic (rnu/+) rats. Release of RMCPII into the blood stream (2.9 micrograms/ml of serum) of normal rats occurred within 1 day after infection. This response developed 3-6 hours after inoculation with oocysts, was dose-dependent, and was found in both naive and immune rats. Maximal release of RMCPII (4.5 micrograms/ml of serum) in naive rats occurs 9 days after primary infection, whereas the numbers of MMC and concentrations of mucosal RMCPII were maximal 14 days after infection, by which time the systemic RMCPII response had begun to decline. The numbers of MMC and concentrations of mucosal RMCPII in uninfected nude rats were similar to those in the heterozygous (rnu/+) litter-mates. After infection, the numbers of MMC and concentrations of mucosal RMCPII increased in the heterozygotes but not in nude rats. Similarly, RMCPII was detected systemically only in the heterozygotes.

Coccidia: A review of recent advances on immunity and vaccine development

“…Mucosal mast cells were also seen to respond during E. nieschulzi infection in rats. Release of a soluble serine protease was greater in infected rats than in controls (Huntley et al, 1985). Additionally, the number of mucosal mast cells per crypt and serine protease concentration were higher during a secondary response compared to the primary (Huntley et al, 1985), indicating the possibility of an anamnestic type response.…”

Immunity in rats against Eimeria separata : oocyst excretion, effects on endogenous stages and local tissue response after primary and challenge infections

“…This appears consistent since dierentiation and growth of mucosal mast cells are also regulated via Th2-type cytokines (reviewed by Else and Finkelman 1998). Mucosal mast cell hyperplasia is not uncommon in coccidial infections and has been described in several Eimeria sp.-host systems, particularly after challenge infections with E. nieschulzi in rats (Rose et al 1980;Huntley et al 1985), E. vermiformis in mice (Rose et al 1992b) and E. ovinoidalis in lambs (Gregory and Nolan 1981). In addition, mucosal mast cell protease was detected in the serum of rats after a primary E. nieschulzi infection (Huntley et al 1985), suggesting a functional role of these cells in the course of infection.…”

“…Similar observations were made in infections of chickens and turkeys with E. acervulina and E. meleagrimitis, respectively (Augustine and Danforth 1986) and in mice with E. falciformis (Mes®n and Bellamy 1979). Conversely, reduced numbers of sporozoites in enterocytes of immune animals were found with E. nieschulzi (Huntley et al 1985), E. tenella (Leathem and Burns 1967;Rose et al 1984;Augustine and Danforth 1986) and E. adenoeides (Augustine and Danforth 1986) infections. It is conceivable that the reduction of numbers of early intracellular stages in immune animals may be related to speci®c antibodies present in the mucus/mucosa of immune animals, which act by directly blocking invasion or by enhancing intraluminal destruction of sporozoites (see Rose and Hesketh 1987); however, there is no current explanation of why these antibodies act only in some avian or mammalian Eimeria infections and not in others.…”

“…Mucosal mast cell hyperplasia is not uncommon in coccidial infections and has been described in several Eimeria sp.-host systems, particularly after challenge infections with E. nieschulzi in rats (Rose et al 1980;Huntley et al 1985), E. vermiformis in mice (Rose et al 1992b) and E. ovinoidalis in lambs (Gregory and Nolan 1981). In addition, mucosal mast cell protease was detected in the serum of rats after a primary E. nieschulzi infection (Huntley et al 1985), suggesting a functional role of these cells in the course of infection. Mast cells can elaborate and secrete several in¯ammatory mediators such as leukotrienes and proteases, which may cause increasing mucosal permeability, facilitating a rapid accumulation of antibodies and eector cells to the mucosal surfaces, and can produce a variety of cytokines which in¯uence immune responses (reviewed by Miller 1996).…”

Murine Goblet Cell Hypoplasia during Eimeria pragensis Infection is Ameliorate by Clindamycin Treatment

“…Indeed, with E. nieschulzi (a small intestinal tropic parasite), the damage to the epithelial surface was greatly reduced in T cell-deficient nude rats despite a dramatic increase in the numbers of parasites developing in the gut [13]. A range of changes in the immune cell populations associated with coccidial lesion has been reported [6,16], including intraepithelial lymphocyte populations [20], mast cells [7,13] and polymorphonuclear cells [20].…”