摘要:

SUMMARYThe ability of human eosinophils to kill the newborn larvae (NBL) of Trichinella spiralis of different maturation status, in the presence of antibody, was studied. A cytotoxic in vitro test was performed using NBL less than 2h of age (NBL2) or NBL maintained in culture at 37°C for 20 h (NBL20), peripheral blood eosinophils, anti‐Trichinella serum and human fresh serum as source of complement. Under these experimental conditions eosinophils from normal individuals attached to NBL2as well as to NBL2o but only the latter were killed. On the other hand, eosinophils from volunteers with eosinophilia killed NBL regardless of larval age. Neither adherence nor significant mortality was observed in the absence of immune serum. These results indicate that NBL maturation and eosinophil activation status are crucial for antibody‐dependent cellular cytotoxic reaction (A

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb00998.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYBALB/c male mice acutely infected with Trypanosoma cruzi underwent a severe weight loss (around 20%, from day 18 to 31 post‐infection), when compared to age‐matched uninfected animals. Though mice regained weight later, when blood parasites were hardly detectable, wasting extended over the chronic phase of infection. The onset and the magnitude of weight loss were related to the mouse susceptibility to infection, since they were respectively earlier and higher in male mice which will die than in surviving ones, in males than in females, and in BALB/c than in B6D2 [(C57B1/6 × DBA/2)F1], a mouse strain more resistant to infection. Fat weight of infected mice (male BALB/c) was reduced by 60 to 80%, whereas lean mass was unaffected and water content rose by 6 to 10% in acute and chronic infection. Haematocrit was also decreased by 15–16% in acute infection. Animals failed to compensate their energetic loss since their food intake remained similar to that of uninfected animals. Injections of neutralizing anti‐TNF‐α monoclonal antibody into infected male mice, during the first two weeks but not later in infection, significantly attenuated the weight loss. Early administration of anti‐IL‐6 or anti‐IFN‐γ MoAbs did not improve the mouse wasting. Taken together, these data show that TNFis a key agent of cachexia occurring in the acute T. cru

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb00999.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYAlthough inbred strains of mice are classified as genetically resistant or susceptible to Leishmania major based upon their ability to control infection, other factors such as the strain, dose, and site of parasite inoculation can also affect the outcome of the disease. Here we used the Fl progeny of BALB/c (susceptible) and C57BL/6 (resistant) mice (designated CB6F1) to investigate whether mice or intermediate susceptibility to infection differed from the parental strains in their ability to control infections at different cutaneous sites. CB6F1 mice developed progressive disease when inoculated in the dorsal skin, but healed infections in the footpad. Consistent with these observations, mice inoculated in the footpad ultimately developed Th1 responses, known to be required for healing, while Th2 responses developed in mice inoculated in the dorsal skin. However, IL‐4 and IFN‐γ production during the first few weeks of infection was similar in CB6F1 mice inoculated at either site, suggesting that factors in addition to the relative levels of these cytokines produced early in infection may influence the nature of the antileishmanial immune response, and the eventual disease outcome. Infection in CB6F1 mice provides a model for the study of immunity to L. major in genetically identical animals, in which a prolonged mixed Thl/Th2 cytokine pattern initially develops, but ultimately diverges into more defined Th1 and Thl type respo

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01000.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYThe present investigation was undertaken to determine whether reserpine‐induced increase in the sulphation of the small intestinal goblet cell mucins of rats affects the establishment of intestinal helminths. When Wistar rats were given daily intraperitoneal injections of reserpine for seven days and were then implanted intraduodenally with 500 Strongyloides venezuelensis adult worms, the number of adult worms established in the intestine of reserpine‐treated rats was about half of that established in controls. Furthermore, when mast cell‐deficient Ws/Ws rats were treated with reserpine and implanted concurrently with S. venezuelensis and Nippostrongylus brasiliensis adult worms, the establishment of the former, but not the latter, was significantly suppressed. These results imply that the physicochemical properties of the mucins produced and secreted by the small intestinal goblet cells may be critical for the establishment of particular species of intestinal helm

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01001.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYIn an attempt to overcome T cell unresponsiveness to filarial antigens, 65 individuals belonging to the three clinical groups of elephantiasis patients, microfilaraemics, and asymptomatic amicrofilaraemics who exhibited unresponsiveness to Brugia malayi adult worm antigen (BmA) were studied. Peripheral blood mononuclear cells were co‐cultured with antigen and one of the following reagents that have been reported to be effective in reconstituting T cell proliferation: interleukin‐2 (IL‐2), interleukin‐7 (IL‐7), anti‐interleukin‐4, anti‐interleukin‐10, anti‐CD2, anti‐CD27, anti‐CD28, indomethacin, phorbol myristate acetate (PMA), or calcium ionophore (A23I87). We were able to overcome antigen‐specific unresponsiveness in only a minority of the individuals studied. Co‐culture with IL‐2, IL‐7, indomethacin and PMA were the only conditions which resulted in enhanced proliferation to BmA in these individuals. In general, unresponsiveness in elephantiasis patients was easier to reverse than in other clinical groups: in 50% of elephantiasis patients, in 12.5% of microfilaraemics and in 20% of asymptomatic amicrofilaraemics. The results indicate that more than one distinct immunological mechanism may account for the antigen‐specific unresponsiveness in individuals exposed to and

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01002.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYStem cell factor (SCF) is a growth factor with multiple activities which acts on numerous cell types including primordial germ cells, haemopoietic stem cells, melanocytes and mast cells. SCF is critical for the development of the mast cell hyperplasia associated with infection with the intestinal parasites Nippostrongylus brasiliensis and Trichinella spiralis. In the present study we have assessed the role of SCF in the mast cell and eosinophil responses to Schistosoma mansoni in the rat by blocking its effects in vivo with polyclonal antibody to SCF. Rats treated with sheep anti‐SCF antibody on days 21, 24, 27 and 30 of infection with S. mansoni showed a rapid decrease in serum concentrations of the mucosal mast cell‐associated protease rat mast cell protease II (RMCP II) by day 24, compared with normal sheep IgG‐treated controls. Similarly, the number of mucosal mast cells and RMCP II levels in both small intestine and liver were also significantly reduced by day 32 of infection. In contrast with the depeletion of mast cells and mast cell proteases, eosinophil numbers in liver or intestine did not change significantly after anti‐SCF treatment compared with controls. These results confirm that mast cell survival and hyperplasia are dependent on the presence of SCF whilst demonstrating that the eosinophil recruitment to liver and intestine associated with S. mansoni infection is SCF‐in

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01003.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYJirds support the entire life‐cycle of Strongyloides stercoralis. We therefore used this host as a model to define the mechanism of the immune response to a challenge infection, as well as the parasite stage effected by the response. Jirds given a primary infection of S. stercoralis are resistant to re‐infection. The use of implanted diffusion chambers containing larvae showed that the immune response killed the third‐stage larvae, and this was confirmed by subcutaneous infections. The larvae of a challenge infection are killed within 48 h, a time period too short to allow for the development of L4 and adult worms. The immune response is dependent on both a serum factor and cells, suggestive of an ADCC type res

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01004.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYHuman IgE responses to helminth infections have been described as both problematic and beneficial, in that type 1 hypersensitivity to parasite infections can reputedly cause pathology and/or parasite expulsion, (Pritchard, Quinnell&Walsh 1995). In the present communication, we can report that the IgE response to helminth infections may be beneficial in a diagnostic sense, in that antibodies of this isotype showed minimal cross‐reactivity against antigens from the parasites tested. This information may be of benefit to workers attempting to establish ELISA assays for the specific diagnosis of zoonotic hookworm infections, for example, Ancylostoma caninum (Croese 1988), particularly in regions where human hookworm infection is endemi

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01005.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY