Serum IgG antibody response to pneumocystis carinii among immunosuppressed, malnourished and healthy rats

In this work, humoral immune responses to Pneumocystis carinii were studied using IFAT during the period of infection and recovery of immunosuppressed and malnourished rats compared to healthy group. Serum IgG antibody titers to the organism were absents in rats administered corticosteroids, but arose after steroid tapering, with disappearance of the organism from their lungs due to reactivation of the immune system. While, in malnourished infected rats, clearance of the organism had occurred after regaining the protein diet with progressive increase in IgG level denoting their immunocompetent state. IgG antibody appeared in the serum of control healthy rats with the progress of age at low non diagnostic level, indicating the presence of dormant parasites in their lungs

Schistosomal nephropathy: effect of cyclosporine A [Csa] in murine schistosomiasis mansoni

The effect of ciclosporin A [CsA] on schistosomal nephropathy in infected mice with Schistosomal mansoni [S. Mansonj] has been investigated. Infected mice were orally treated with 50 mg/kg body weight of CsA for 5 consecutive days at the 8[th], 12[th], 16[th] week postinfection [p.i.]. Four weeks after drug therapy, CsA aborted and retarded the progression of glomerular injury in all stages of the disease; particularly with early drug therapy. This was evidenced by the reduction in electron dense deposits and weak positivity by fluorescent microscope. This response was accompanied by amelioration of hepatosplenomegaly. The effects of CsA could be related to its known immunosuppressive effect on T-helper [Th] cells. Moreover, CsA had a profound anti-schistosomal activity as demonstrated by the significant decrease in worm burden specially female worms, and the increase in the percentage of mature and dead eggs in intestinal mucosa in this study. So, CsA would ameliorate the glomerular lesion in early stages of schistosomal nephropathy, mainly by its immunosuppressive effect, but in later stages, the direct anti-schistosomicidal effect would take the upper hand

Gastro-vascular and micro-vascular changes in chronic murine schistosomiasis mansoni: response to propranolol

Histopathologic study of the gastric wall of mice infected with Schistosoma mansoni was carried out at 8, 12, 16 and 20 weeks postinfection [p.i.]. The gastric vascular structures were more sensitive to injury with the progression of liver disease than the glandular cells, with marked submucosal edema and thickening of submucosal and subserosal vessels. By transmission electron microscopy, the mucosal microvessels had thickened basement membrane and conspicuous endothelial cells with granular cytoplasm thrown into numerous intraluminal microprojections and with increased number and size of pinocytotic vesicles. When propranolol was administered orally as 20 mg/kg daily doses for two weeks at 6, 10, 14 and 18 weeks p.i., a striking regression of gastro-vascular and micro-vascular changes has been observed, particularly with early drug therapy. Based on the present study, it can be concluded that "structural autoregulation" of gastric vasculature to the emerging portal hypertension in chronic murine Schistosomiasis mansoni, is a dynamic process that could be reversed by propranolol therapy. This response could, possibly, improve gastric mucosal perfusion and functional abnormalities which may predispose the gastric mucosa to severe damage or hemorrhage

Effect of capillaria hepatica infection on schistosoma mansoni challenge in mice

The combined infection between Capillaria hepatica and Schistosoma mansoni was studied. The results of this work revealed that C. hepatica infection induced significant reduction of S. mansoni worm load in the two groups infected with C. hepatica and challenged with S. mansoni either during worm maturation period of C. hepatica, or at the time of presence of C. hepatica eggs in the liver. Reduction in total and tissue egg count was also reported, but eggs excreted in the stool showed no difference in count from that of S. mansoni-infected controls. Oogram pattern of the experimental groups revealed a higher percentage of dead eggs and absence of mature and some developing stages. Scanning electron microscopy demonstrated severe destruction of adult worm of both groups. All these data showed the vigorous destructive effect of C. hepatica infection on the challenged S. mansoni