摘要:

SummaryThe characteristics of primaryNematospiroides dubius, mouse‐adaptedNippostrongylus brasiliensisandTrichuris murisinfections in C57BL mice and their broad effects on lymphoid tissue and reticuloendothelial function have been compared in an attempt to identify correlations between the effects of the parasites and common features of their life cycles.All three parasites increased the size of the spleen and mesenteric node, roughly in proportion to the intestinal worm burden.N. brasiliensisandT. muriscaused thymic atrophy, which was not evident withN. dubiuseven when it was administered intravenously (i.v.) to establish a tissue migration phase.N. brasiliensisaccelerated the clearance of I125‐labelled polyvinyl pyrrolidone (I125‐PVP) from the circulation by increasing uptake by the liver and lungs.N. dubiuscaused similar increases when given i.v., suggesting that macrophages in these organs are activated by migrating larvae, but did not affect the levels of I125‐PVP in circulation. An established intestinalN. dubiusinfection increased the levels in circulation and in peritoneal cells.

ISSN:0004-945X    

DOI:10.1038/icb.1983.35

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryInfection with Trichuris muriseggs orNematospiroides dubiuslarvae (orally administered) did not affect IgG or IgM antibody responses to 0·2 μg polyvinyl pyrrolidone (PVP) (intravenously (i.v.) or intraperitoneally (i.p.)) or 20 μg PVP (i.p.) in C57BL mice. However,Nippostrongylus brasiliensisL3 subcutaneously (s.c.) andN. dubiusL3 (i.v.) significantly increased responses to PVP (i.p.) so migrating larvae are probably responsible. Similar enhancement was obtained when extracts ofN. brasiliensisworms orN. dubiuslarvae were administered i.p. The activity ofN. brasiliensisextract was trypsin‐insensitive and unaffected by heat (1 h, 60°). Extracts ofA. suumdid not cause significant enhancement and BALB/c mice were not affected byN. brasiliensisextract. The possible roles of regulatory T‐cells, non‐specific mitogenesis and macrophage activation are discussed.

ISSN:0004-945X    

DOI:10.1038/icb.1983.36

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryNematospiroides dubius, Nippostrongylus brasiliensisandTrichuris murisinfections in C57BL mice increased background IgM titres to SRC but not to erythrocytes from other species. However, no cross‐reaction between parasite extracts and SRC could be demonstrated and the enhancement was not evident in other strains of mice. There were no comparable rises in total IgM levels, but declining IgM responses to ovalbumin were boosted byN. dubius, so the rise was probably caused by selective expansion of activated clones of cells.N. dubiusalso increased responses to low doses of SRC given intraperitoneally (i.p.) a few days after infection, whilst optimal SRC doses induced normal responses. In contrast,N. brasiliensisandT. murisoften depressed responses to SRC though the effect was variable and the timing of challenge was critical. Thus, whereas the enhancement of natural titres occurs in C57BL mice infected with any of the parasites tested here or in previous studies, the effects on responses to injected SRC depend on the species of parasite.

ISSN:0004-945X    

DOI:10.1038/icb.1983.37

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryA radioisotopic assay for acute granulomatous hypersensitivity (AGH) to lyophilized eggs ofSchistosoma japonicumhas been used to further examine responses to egg antigens in various inbred strains of mice. The ranking of responsiveness in mice from high (C57BL/6), intermediate (BALB/c) to low (CBA/H) was not influenced by high or low egg‐sensitization regimes. However, the low responsiveness of responder mice sensitized with eggs by the intraperitoneal compared with the subcutaneous route of injection appears to be an egg dose‐related phenomenon. The high AGH responsiveness of C57BL/6 mice can be increased further by sensitization with eggs in the presence of purified pertussigen fromBordetella pertussisbut CBA/H mice treated identically remain low responders.The monoclonal anti‐egg antibody, P.41, which produces a prominent blebtype circumoval precipitate with eggs, has been shown to be directed against major ‘immunopathologic antigen(s)’ofS. japonicumeggs. Thus, C57BL/6 mice were sensitized for AGH by injection of soluble extracted egg antigen (SEA) bound to an immunoabsorbent of P.41 antibody on Sepharose. No success has been achieved in modulating AGH in C57BL/6 mice by injection of hyperimmune antisera raised against lyophilized eggs in either high or low responder mouse strains. This failure is in line with previous results using antisera as well as monoclonal anti‐egg antibodies. The consistent failure to demonstrate a modulating effect of antibodies in this compared with other laboratories may be related to the use of lyophilized rather than viable eggs. The data suggest that activities of antisera in granuloma modulation in murine schistosomiasis japonica result from egg destruction or inhibition of production of immunopathologic antigens by eggs rather than through effects on immunopathologic immune responses.

ISSN:0004-945X    

DOI:10.1038/icb.1983.38

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryThe intestinal nematodeNematospiroides dubiuspersists for prolonged periods in mice after a single oral administration of infective larvae. After multiple administrations of larvae, some inbred mouse strains (termed ‘resistant’) develop the capacity to expel the majority of adult worms from the intestines. Other mouse strains such as CBA/H and C57BL/6 (and, in particular, males) are far more susceptible in that they expel few, if any, adult worms after repeated doses of larvae and may die with high worm burdens. One means to accelerate rejection of adult worms in a primary infection is to presensitize mice with a small number of living adult worms injected intraperitoneally. However, an impressive vaccination effect of ectopically implanted worms has only been demonstrated to date in resistant mouse strains. In this paper, success has been achieved in vaccinating geneticallysusceptiblemice against chronic primary infection withN. dubius. Young male specific pathogen‐free (SPF)‐derived C57BL/6 mice demonstrate>90% resistance after injection of adult worms but only when further injected with pertussigen fromBordetella pertussisas adjuvant. Accelerated rejection of adult worms appears to be the principal manifestation of resistance in vaccinated mice. A high degree of protection has also been obtained in recipients of pertussigen plus the supernatant of a crude worm extract equivalent to<10 adult worms per mouse. Although no information is available on the effector mechanisms responsible for worm rejection in vaccinated mice, pertussigen is known to increase both immediate and delayed type hypersensitivity responses and to increase tissue sensitivity to histamine. A strategy which sensitizes recipients such that a subsequent challenge infection is not sustained, and which is effective in highly susceptible hosts, opens the way to vaccination against chronic intestinal infections in those hosts most in need of protection.

ISSN:0004-945X    

DOI:10.1038/icb.1983.39

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

ISSN:0004-945X    

DOI:10.1038/icb.1983.40

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryWe investigated the development of astrocytes in mechanically dissociated primary cultures of foetal and neonatal rat brain grown in different culture media using immunofluorescence and antiserum to glial fibrillary acidic protein (GFAP). GFAP‐positive cells developed at a time corresponding to the 16th day of embryonic development and initially grew more slowly in Dulbecco's modified Eagle's Medium (DMEM) than in Medium 199 (M199) or Modified Eagle's Medium (MEM), but as the cultures matured a greater proportion of GFAP‐positive cells was obtained in DMEM, resulting in relatively pure populations of GFAP‐positive cells after 1–2 monthsin vitro. GFAP‐positive cells comprised process‐bearing and fibroblastoid cell types and cells with intermediate morphology. Cultures in DMEM were also characterized by the appearance after 8–18 daysin vitroof thick long bands of glial processes surrounding cyst‐like spaces. The morphological change may represent a gliotic reaction to necrosisin vitro.

ISSN:0004-945X    

DOI:10.1038/icb.1983.41

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryThis study investigated the inhibition by colostrum of the uptake of tritiated thymidine by both autologous and heterologous peripheral blood mononuclear cells (PBMC) stimulated with the mitogens phytohaemagglutinin (PHA), pokeweed mitogen (PWM) or Concanavalin A (Con A). This inhibition was not the result of an alteration in the dose response or kinetics of mitogenesis by the colostrum. The inhibitory factor in the colostrum was neither dialysable nor lymphocytotoxic. Lymphocytes which were briefly pre‐treated with colostrum, then washed and cultured, also incorporated much less labelled thymidine than control cells. The inhibitory factor was not adsorbed from colostrum by mononuclear cells. We conclude that colostrum contains a cytostatic factor which inhibits mitogenesis in PBMC.

ISSN:0004-945X    

DOI:10.1038/icb.1983.42

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummarySubsets of natural killer cells may be characterised by the target cell profile, cell surface markers and the effect of growth factors on the production of effector cells. The subset which appears in primary cultures (spontaneous or natural T killer cells) is enhanced by the supernatants of Con A‐stimulated rat spleen cultures. The enhancement can be attributed to an increased number of clones rather than an expansion of clone size in 5‐day cultures. With semi‐purified IL‐2 preparations, clones of spontaneous cytotoxic cells are also detectable in nu/nu spleen cultures. These results suggest such spontaneous cytotoxicity is a general phenomenon within cytotoxic responses.

ISSN:0004-945X    

DOI:10.1038/icb.1983.43

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY

摘要:

SummaryThe vaccinia‐virus‐immune cytotoxic T lymphocyte (CTL) response, associated with H‐2Kkin B10, A(2R) [KkDb] mice, is much more potent than that occurring in the context of H‐2Db. This differential reactivity is true for T‐cells recovered either from cerebrospinal fluid (CSF) of mice injected intra‐cerebrally (i.c.) with a low dose of virus or from spleen populations primed by intravenous (i.v.) inoculation of a large amount of virus. Further stimulation of CSF inflammatory cellsin vitrofor 7 days under limiting dilution conditions indicated that the hierarchy of cytotoxic T‐cell activity was a function of the relative frequencies of H‐2Kk‐ and H‐2Db‐restricted lymphocytes. We therefore conclude that the immune response gene effect described previously for cells found in lymphoid tissue is also expressed in a virus‐induced inflammatory exudate in the central nervous system.

ISSN:0004-945X    

DOI:10.1038/icb.1983.44

出版商:Nature Publishing Group    

年代:1983

数据来源: WILEY