ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb01608.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb01609.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb01610.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Injection of mice with rat erythrocytes (RRBC) has long been thought to provide an experimental model in which suppressor T cells (Ts) control autoimmunity. The basis of this is that whilst mice immunized with RRBC produce an antibody response, of which a proportion cross‐reacts with autologous red cells, the RRBC‐immunized recipients of RRBC‐primed spleen cells make no, or little, autoantibody, and secondly because the transfer of this autoantibody‐specific suppression can be abrogated by T‐cell depletion of transferred spleen cells. Here an alternative explanation of these phenomena is

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb02934.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

We have defined a strategy for the development of a T‐cell vaccine for blood stage immunity, taking into consideration the central role of T cells and MHC restriction in malaria immune responses. We have used the AMPHI computer algorithm lo identify putative T‐cell epitopes from conserved regions of 11Plasmodium falciparumasexual stage proteins. Ten of the eleven proteins arc currently candidates for vaccine development. Using this algorithm we selected 22 putative T‐cell epitope peptides und 8 control peptides. These peptides were used to test the T‐cell responses of three defined populations of Caucasians who have (1) recovered fromP. falciparummalaria. (2) been exposed, but never clinically infected, (3) never been exposed or infected. Preliminary analysis of our data shows population differences in T‐tell responses to putative T‐cell epitope peptides. Ultimately, these studies will help to identify those T epitopes that can be incorporated into a T‐cell vaccine for protec

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb01611.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

The binding of a 34‐kDa (mol. wt.) acylpoly(1,3)galactoside (APG) extracted from a membrane proteoglycan ofKlebsiella pneumoinaeto human blood leucocytes was investigated. APG is made of a long polyl (1,3)galactose chain, a core‐like region and a lipid moiety which comprises two glucosamine residues bound to a phosphate group and two βOHmyristic acids, Fluoresceinated APG was shown to bind preferentially to monocytes and to a lesser extent to polymorphonuclear neutrophils, as determined by flow cytometry. Binding of fluoresceinated APG was inhibited by unlabelled APG; it was concentration dependent, but not saturable, with rapid kinetics. It occurred at +4°C but was markedly increased at 37°C. It involved trypsin‐sensitive molecules on the membrane of monocytes. Neither the parent proteoglycan nor lipopolysaccharide fromK. pneumoniaeorSalmonella minnesotacompeted for APG binding. A minor non‐specific binding to lymphocytes, occurring predominantly on B cells, was observed. Unlike that of lipopolysaccharide, the APG binding was not blocked by polymyxin B sulphate. Interaction between the galactose chain of APG and the galactose receptor does not account for the binding of APG to monocytes because the galactose receptor (Mac‐2) is expressed at high density on activated macrophages but not on monocytes. Despite its strong binding to human blood monocytes, APG displayed a much weaker activity thanK. pneumoniaemembrane proteoglycan with respect to induction of monocyte cytokine synthesis. When administered as a Technetium 99 conjugate, APG was shown to label inflammatory foci in experimental animals, and its property as a marker of macrophages is currently being evaluated in cli

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb02935.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Malarial infections are rarely observed in neonates. It has been postulated that some immunity may be passively transferred during nursing, but anti‐malarial antibodies (Abs) have not been detected m human milk. In this study, milk samples, collected 2‐14 days after parturition from women at the Central Maternity Hospital, Yaounde, were evaluated for total IgG and IgA antibody levels by radial diffusion, protein composition by SDS PAGE, anti‐malarial antibodies using an isotype‐specific immunofluorescence assay, and the ability to immunoprecipitatePlasmodium falciparumantigens metabolically labelled with35S‐methionine. Results showed that anti‐P. falciparumantibodies were present in breast milk, and that paired milk and serum samples from individual women contained Abs that recognized similar malari

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb01612.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

We report a case of common variable immunodeficiency (CVI) that shows low levels of IgG and IgA, but a normal quantitative or qualitalive level of IgM. T‐cell functions were not disturbed. Increased numbers of surface IgM (sIgM) and sIgD, sIgM and sIgA, sIgM and sIgA double bearing B cells were observed as compared with a control. No IgG and IgA induction upon stimulation withStaphylococcus aureusCowan I (SAC)and recombinant interleukin‐2(rIL‐2), or pokeweed mitogen (PWM) and rIL‐4 or rIL‐6 was observed, although there was proliferation. Although; μ mRNA was expressed as much as in a healthy control, transcription of γ mRNA and α mRNA was very low. Furthermore, no enhanced effects of γ mRNA and α mRNA were recognized upon stimulation with rIL‐4 and rIL‐6. These results suggest that the patient's B cells might be detective at the switching process from μ, μ and δ, μ and

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb02936.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Pilot experiments were carried out to assess the immunizing potential of radiation‐attenuated cercariae ofS. mansoni.Groups of 4 monkeys each were vaccinated 4‐5 times at 3‐5‐week intervals using cercariae which had received 10, 20, 40 or 60 krad of gamma radiation. Animals were vaccinated with 1000 or 2000 cercariae per kilogram of body weight. Overall the difference in trans burdens between the vaccinated and unvaccinated groups was highly significant (P>0.01). The highest level of protection achieved was 44.4%. This was in monkeys which were immunized live times with 2000, 20‐krad cercariae at 3–4‐week intervals. Protection levels of 33.3%, 36.6% and 37.0% were achieved in groups which had received, respectively, 1000 20‐krad cercariae, 1000 10‐krad cercariae, 2000 40‐krad cercariae and 2000 60‐krad cercariae. Vaccination reduced faecal egg counts markedly and intestinal tissue egg cotints by 20–40%. Antischistosomular antibody was detectable in vitro 3 weeks after the first vaccination. Schistosomule kill rates of up to 60%

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb01613.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

IL‐1 is a mediator of the acute inflammatory response and plays a key role in influencing growth and differentiation of immunocompetent lymphocytes. It can enhance transcription and secretion of the T‐cell growth factor interleukin‐2 (IL‐2) and can stimulate the expression of membrane receptors for IL‐2. However, the regulation and control of IL‐1 activities are poorly understood. Recently an IL‐1 inhibitor, interleukin‐1 receptor antagonist (IL‐1ra), has been described and cloned. This protein is a monokine originally found in the urine of febrile patients and in supernatants of human monocytes adhering to an IgG‐coated surface, with an approximate molecular weight of 17 kDa, which is similar to IL‐1β but having no IL‐1‐like activity and antagonizing IL‐1 by binding to its cell surface receptor.These studies have examined some biological properties of hrIL‐1ra, such as its effects on the secretion of IL‐1α or IL‐1β and IL‐2, the surface expression of 1L‐2R and DNA synthesis by peripheral blood mononuclear cells (PBMC). PBMC from normal volunteers were separated and used at a concentration of 2.5 x 106cells/ml. The cells were pretreated for 2h with hrIL‐1ra (0.025‐250 ng/ml), treated with LPS (10 ng/ml), and IL‐1α and IL‐1β secretion were determined by an ELISA method. In addition the influence of hrIL‐1ra (25 ng/ml) on IL‐2 generation was determined. In another set of experiments, flow cytometric analysis with an anti‐CD25 monoclonal antibody was determined on PHA‐stimulaled PBMC pretreated wilh hrIL‐1ra (2 h) and cultured for 48 h. The inhibition by hrIL‐1ra of IL‐2R expression was dose‐dependent and when hrIL‐1ra was used at 250 ng/ml the IL‐2R was completely abolished. Lymphocyte DNA synthesis calculated from the net uptake of [3H]‐thymidine (3H‐TdR) was also inhibited by hrIL‐1ra (0.025‐25 ng/ml). In this report we found that hrIL‐1ra inhibits, in a dose‐dependent manner, the secretion of IL‐1α, IL‐1β, IL‐2, the surface expression of IL‐2R and3H‐TdR incorporation in PBMC in vitro. These data suggest a new biological activity of hrIL‐1ra and further extend the immunomodulatory potential and significance of this new cytokine. The action of IL‐1ra on

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb02937.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY