Intestine Of Infected Mice Research Articles

Synergistic action of a cyclic depsipeptide and piperazine on nematodes.

The present study describes the synergistic effects of the cyclic depsipeptide BAY 44-4400 and piperazine in the treatment against the nematodes Trichinella spiralis, Heligmosomoides polygyrus, and Heterakis spumosa. The in vitro anthelmintic activity of a combination of the two compounds (1.7 motility units) against T. spiralis larvae was significantly higher than the sum of the individual drug effects (1.3 motility units). With regard to the rate of expulsion of H. polygyrus worms from the intestine of infected mice, an additive effect was observed; piperazine alone exerted an efficacy of 54.4% and BAY 44-4400 alone, one of 44.4%, whereas the combination of these compounds had an efficacy of 97.5%. With regard to the expulsion of H. spumosa worms, the effect of the combination was more than 5 orders of magnitude greater than the sum of the effects of the single compounds, i.e., there was a considerable potentiation of the actions of BAY 44-4400 and piperazine. Moreover, the combination exerted a significantly higher degree of degenerative effects on the intestine and on the nerve chords of H. spumosa as compared with the single compounds.

Effects of a protein-free diet on worm recovery, growth, and distribution of Echinostoma caproni in ICR mice

The effects of a protein-free diet on the host-parasite relationship of Echinostoma caproni in ICR mice were studied. The experimental diet was a customized protein-free diet (PFD) in pellet form containing 0% protein. The control diet consisted of a standard laboratory diet containing 23% casein as a source of protein. A total of 24 mice were each infected with 15 metacercarial cysts of E. caproni. Twelve mice were placed on the experimental diet (experimentals) and the remaining mice (controls) were placed on the control diet. Experimental and control mice were necropsied at 2, 3, and 4 weeks postinfection (p.i.). The weight of mice on the PFD was markedly lower than that of mice on the control diet. The length and circumference of the small intestine of infected mice on the PFD were significantly lower than those of the controls at 3 weeks p.i. (Student's t-test; P < 0.05). Worm recoveries from mice on the PFD were significantly lower than those of the controls at 3 weeks p.i. There was a significant decline in worm body area in worms from the mice on the PFD compared with those on the control diet at 2, 3, and 4 weeks p.i. Worm dry weights from mice on the PFD were significantly lower than those on the control diet at 2 weeks p.i. Worms from hosts on the PFD were located more posteriad in the gut than those recovered from mice on the control diet. The findings suggest that the PFD contributes to growth retardation of E. caproni in ICR mice.

Gut-Derived Intraepithelial Lymphocytes Induce Long Term Immunity AgainstToxoplasma gondii

AbstractIntraepithelial lymphocytes (IEL) of the intestine represent an important barrier in the prevention of infection against orally acquired pathogens. Adoptive transfer of Ag-primed IEL into a naive host can protect against challenge. Using a murine model, we demonstrate in two genetically distinct mouse strains (C57BL/6 and CBA/J) that protective IEL can be isolated at specific times after oral infection with cysts containing bradyzoites. Adoptive transfer of IEL obtained from the intestine of infected mice at these specific times can provide long term protection, as determined by mortality and cyst number against challenge. The protective IEL appear to be CD8+, TCR-α/β and are at least partially dependent upon the presence of TCR-γ/δ T cells in the host. Endogenous production of the pivotal cytokine, IFN-γ, is essential for host immunity. These findings demonstrate that gut-derived IEL represent a potentially important mechanism to provide long term immunity to the host.

Vasoactive intestinal peptide stimulates T lymphocytes to release IL-5 in murine schistosomiasis mansoni infection.

In murine schistosomiasis, granulomas form around ova deposited in the liver and intestines of infected mice. The granulomas have eosinophils that produce vasoactive intestinal peptide (VIP) and T cells that display VIP receptors. IL-5 is a lymphokine important for the development and maturation of eosinophils. It seemed plausible that VIP, released from eosinophils, may interact with lymphocyte VIP receptors and modulate IL-5 production as part of a feedback regulatory circuit. Thus, we determined whether granuloma T cells make IL-5 and whether VIP modulates IL-5 production. Isolated granuloma cells enriched for T lymphocytes spontaneously released IL-5. Culture of these cells in the presence of VIP increased IL-5 secretion. Spleen cells were also studied. Spleen cells from infected mice did not spontaneously release IL-5 or express IL-5 mRNA and VIP did not stimulate these resting spleen cells to produce this IL. However, these cells did express IL-5 mRNA and secreted IL-5 in response to Con A or soluble egg Ag. VIP could not appreciably modulate IL-5 release when cells were cultured with VIP and the Ag or mitogen. Spleen cells washed free of Con A ceased IL-5 secretion within 24 h. These preactivated splenic T cells resumed vigorous IL-5 secretion in response to either Con A or VIP. Yet only Con A prominently induced IL-5 mRNA expression. VIP was an effective stimulus at concentrations equal to or above the kDa of the VIP receptor on both splenic and granuloma T cells (10(-8) M). It is concluded that, in murine schistosomiasis, VIP invokes IL-5 release from activated T cells that are not undergoing immediate TCR stimulation.

The effect of the intestinal worms and migrating L1 larvae of Trichinella spiralis on the production of antiparasitic IgE antibodies.

The effect of the adult worms and migrating L1 larvae of Trichinella spiralis on the production of specific IgE antibodies was determined in BCF1 mice. To achieve this, we combined the effect of two anthelminthics: thiabendazole, to produce chemosterilization of adult females, and napthalophos, to expel adult worms from the intestine of infected mice on the desired day. Our results demonstrate that when the natural route of infection is used the production of IgE antibodies is not dependent on the infection dose or the number of migrating L1 larvae, and that both intestinal worms and migrating L1 larvae contribute to the production of reaginic antibodies. In addition to this, an extended period of antigenic stimulation (10-12 days) is required for the induction of a detectable, specific IgE response by adult worms. Finally, our results seem to indicate that although the effects of adult worms and migratory L1 larvae on the IgE production are not additive, the presence of adult worms in the intestine of mice may stimulate a secondary exposure to common antigens released by the migrating L1 larvae.

Oral infection of mice with trophozoites of Giardia muris.

Giardia muris has been maintained for years in the mouse by administering by gavage 10,000 trophozoites taken from the small intestine of infected mice. Despite the growth of numerous protozoa in the intestine, absorption of tetracycline hydrochloride in infected mice was not changed to a statistically significant extent, as blood drug levels increased only slightly: behavior was similarly unaffected. Reasons for the apparent lack of virulence of this strain are discussed.

Purification and characterization of epizootic diarrhea of infant mice virus.

Epizootic diarrhea of infant mice virus has been purified from the intestines of infected mice using enzymatic digestion, precipitation with polyethylene glycol, extraction with Genesolv-D, and sucrose step-gradient centrifugation. The purified virus was found to be stable at -70 C or when treated with ether, chloroform, or sodium deoxycholate. Biochemical analysis of purified virions has suggested that the nucleic acid type of epizootic diarrhea of infant mice virus was of the ribonucleic acid type. Preparations of purified virions stained with phosphotungstic acid showed a particle with icosahedral symmetry, 54 +/- 2 nm in diameter and probably composed of 32 hollow capsomeres.

INACTIVATION OF MHV-3 VIRUS BY INTESTINAL CONTENT AND INTESTINE OF NORMAL MICE.

IN previous work we reported on certain biochemical changes in experimental (MHV-3 virus)1 and in human viral hepatitis2,3. This communication deals with the behaviour of MHV-3 virus4, eliminated with bile in the intestine of infected mice. Because of evidence of virus inactivation in the intestine, experiments were also carried out on the effect of intestinal content and intestine from normal mice on MHV-3 virus.

SCHISTOSOME OVA: RAPID SEPARATION FROM MOUSE TISSUE BY DIGESTION WITH PINGUINAIN.

High yields of ova of Schistosoma mansoni were obtained from the livers and intestines of infected mice by digestion of the homogenized tissue with the proteolytic enzyme pinguinain.