摘要:

SummaryMuscle and neuronal cell lines were infected withTrypanosoma cruziand stained for the presence of parasite antigens by immunofluorescence. Up to 72 h post infection, fluorescence was limited to the intracellular amastigote stages. After the release of parasites, at about 96 h, fluorescence was also associated with the membranes of normal and infected cells. This finding was reproduced by passive sensitization of uninfected cells using amastigote antigens at protein concentrations as low as 10 μg ml‐1. Intriguingly, although both normal and transformed cells of muscle and nervous tissue origin adsorbed significant quantities of antigen, lymphocytes and erythrocytes failed to show any detectible upta

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1980.tb00039.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryThe histopathological responses to the nematodeStrongyloides rattihave been studied in rats following single and multiple percutaneous infections. Under these conditions, rats developed an effective immune response which was shown to be retrophasic, i.e. during primary infection, adult worms in the small intestine were the main target of the response: during secondary infection, the intestinal and, more strongly, the pulmonary phases were affected; following multiple infections, the response was principally effective during the cutaneous phase. An increase in the number of tissue eosinophils in all these sites was a common feature which varied according to the level of immunity acquired by the host. There was an increase in the percentage of degranulated mesenteric mast cells which coincided with the expulsion of the intestinal phase during primary and secondary infections. No direct contact between eosinophils and any stage of the parasite was seen in the small intestine or lungs of normal and immune rats during primary and secondary infections. However, in the skin of hyperimmune rats, eosinophils increased rapidly (within 3–6 h) forming eosinophil‐rich granulo‐mata in which eosinophils were seen in close contact with the cuticle of the invading larvae. This may suggest anin vivoeffector role for these cells. This and other possible roles of eosinophilsin vivohave been discussed in the light of thein vitroaction of eosinophils in other parasitic systems. Both the tissue eosinophil response and the percentage of degranulation of mesenteric mast cells, during the intestinal phase, were affected following treatment with corticoste

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1980.tb00040.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryConcentrations of C3b inactivator (C3bINA) and β1H globulin, two proteins which regluate turnover of the alternative complement pathway, have been measured in the sera of 38 patients with Gram‐negative bacteraemia at the onset of fever, prior to the onset of shock. The mean serum concentrations of these two proteins was reduced compared with normal controls (t = 1.8250, P<0.05 for C3bINA; t =3.9555, P<0.005 for β1H These reductions were most pronounced in those patients who subsequently developed shock, with or without a fatal outcome. Serum levels of C3bINA and β1H correlated well with levels of C3 factor B, but only poorly with C4. C3bINA, but not β1H, also correlated with properdin. As a result of these findings it has been suggested that low serum concentrations of C3bINA and β1H in Gram‐negative bacteraemia, may predispose to excessive alternative pathway

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1980.tb00041.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryAdultFasciola hepaticawere placed intraperitoneally into rats which had been sensitized by an oral infection of 20 metacercariae given 3–5 weeks previously. Implanted flukes were recovered at intervals during the next 24 h. Wax embedded sections of flukes and surface impressions of attached cells were examined by light microscopy (LM). Flukes were also examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In all stages, post transplantation, increased secretory activity was noted at the tegu‐mental surface both by the blebbing of membrane and the formation of microvilli. Monitoring of the surface by SEM revealed attachment of very few cells (less than 100/sq mm) in the first hour. By TEM some of these were found to be eosinophils. At 1.5 h local palisading of cells, mainly eosinophils, occurred. Many of these degranulated at a distance from the parasite. Between 2 and 4 h many more neutrophils and macrophages were found, with fewer eosinophils. In the period up to 4 h the tegumental syncytium became charged with abnormally high concentrations of secretory granules and the surface membrane was maintained often enclosing apparently damaged areas. No cells penetrated the syncytium at this stage. Between 4 and 12 h the number of secretory granules in the tegument declined. Around 12 h the remaining granules contributed to the formation of large irregular microvilli. It was at this stage that neutrophils, macrophages and occasional eosinophils moved into the syncytium and began to lift it from bene

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1980.tb00042.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryAntigenic variation has been demonstrated throughout a chronic infection ofTrypanosoma brucei(derived from TREU 667) in the mouse. The variant antigenic types (VATs) detected were compared with those appearing on transmission from various time points through the infection. Reversion of VAT was found to occur on transmission throughGlossinaregardless of the VAT(s) present at the time of ingestion. The first patent parasitaemia after transmission is heterogeneous with regard to VAT; three predominant VATs appearing consistently. Indirect evidence suggests that this VAT heterogeneity is most likely not reflected in the metacyclic population but comes about immediately on transmission and can occur in the absence of antibody.

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1980.tb00043.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryPretreatment of mice with cyclophosphamide (CY) increases susceptibility of adult mice to herpes simplex type I (HSV‐I) infection. In searching for a CY sensitive mechanism, our attention has been focused on natural killer (NK) cells. Activity of these cells was increased in spleens of adult mice after inoculation with HSV‐I and depressed after CY administration. The timing of recovery of NK cell activity after the administration of CY, was consistent with a role for these cells in collaboration with immune T lymphocytes when transferred to pre‐treated, virus infected animals. It is postulated that sensitized T lymphocytes reacting with virus antigens release products that activate macrophages which in turn produce interferon. Interferon increases NK cell activity and NK cells inhibit viral replication. A correlation between resistance to HSV‐I infection and NK cell activity of CBA or C57BL/10 mice was found. It is suggested that NK cells play a role in defence, not only against tumour cells, but also against a wide range of infective

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1980.tb00044.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY