摘要:

SummaryFourteen mAb specific for human sperm membrane antigens were selected to investigate their inhibitory effect on fertilization. The antigens were not expressed in other human somatic tissues but were present in sperm from other species. The antibodies were purified from ascites fluid produced in mice. The zona‐free hamster egg penetration assay was used for the evaluation of the blocking ability of these antibodies. The inhibition rate was generally related to a decrease in the number of adherent sperm. Three groups of antibodies were distinguished: (i) four mAb that have high inhibition at concentration; (ii) four mAb with an intermediate inhibitory effect, that is more dependent on the antibody concentration tested; and (iii) six mAb with little or no effect at any concentration. The presence of antibodies leads to a lower penetration index, or number of penetrating sperm per oocyte.MAb specific for head antigens promote high inhibition of fertilization; these antibodies show a patchy staining on the sperm head. The antibodies localized in the midpiece have an intermediate inhibitory effect. No inhibition is detected with the equatorial region binding pattern. Sperm agglutination does not play any role in the inhibition caused by the antibodies described here.

ISSN:0004-945X    

DOI:10.1038/icb.1994.1

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe peripheral blood of patients with rheumatoid arthritis (RA) contains oligocional γ/δ T cell populations which may contribute to the pathogenesis of the disease. To investigate whether there is persistent γ/δ T cell oligoclonality in RA peripheral blood, we screened polymerase chain reaction‐amplified T cell receptor (TCR) cDNA, derived from peripheral blood mononuclear cells (PBMC) of four RA patients, with sequence specific oligonucleotides (SSO). The SSO used were specific for TCR variable (V)δ1, Vδ2 and Vγ9 transcripts comprising V‐joining (J) junctions found over‐represented in PBMC of the same RA patients, when bled up to 3 years previously. The dominant transcripts were expressed in the new PBMC samples, although in most cases at a lower frequency than was originally detected. In one patient there was almost 100% oligoclonality of Vγ9‐(N)‐Jγ2 junctional region sequences among the Vγ9 cDNA clones. progressing from 55% oligoclonality in 15 months. These results indicate the persistence of clonally expanded γ/δ T cells in the peripheral blood of RA patients. Whether this reflects continual endogenous or exogenous antigenic stimulation remains to be investigated. The findings presented in this report may have important therapeutic implications in view of the potential for immuno‐intervention for the treatment of human autoimmune disorders, like RA.

ISSN:0004-945X    

DOI:10.1038/icb.1994.2

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryWe describe a novel activation antigen recognized by the monoclonal antibody CMRF‐37, which is absent or only weakly expressed on resting cells but is rapidly induced on T cells, B cells and monocytes following stimulation. Its kinetics of expression (12–24 h after the addition of the inductive signal) indicate that it is an early activation antigen. The cellular distribution and expression kinetics of the CMRF‐37 antigen differ from other known activation antigens and as such should be a useful marker of human leucocyte activation.

ISSN:0004-945X    

DOI:10.1038/icb.1994.3

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe Gerbich‐negative blood group types are rare in most populations, but reach appreciable frequencies in certain Melanesian groups in Papua New Guinea. The recent cloning of the human glycophorin C (GPC) gene, that encodes Gerbich (Ge) blood group antigens, has facilitated study of its genetic variants. We have obtained partial genomic clones of a normal GPC gene, for molecular analysis of Ge: −1,−2,−3 types in Melanesians, and have shown that a 3.5 kb deletion in the GPC gene that removes all of exon 3 accounts for at least one Gerbich‐negative phenotype in Melanesians. Population distributions of GPC RFLP have shown that the deletion‐type GPC is not confined to mainland Papua New Guinea as previously thought, but occurs sporadically in Melanesians from Fiji as well as in Micronesians.

ISSN:0004-945X    

DOI:10.1038/icb.1994.4

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryFeeding protein antigens to mice normally leads to the development of oral tolerance but under some circumstances, feeding can lead to immunity, for example, following pretreatment of mice with cyclophosphamide (CY). In both cases, however, it is possible to detect sensitized T cells in the spleen and mesenteric lymph nodes (MLN) byin vitrolymphokine release for granulocyte‐macrophage‐CSF (GM‐CSF) and IFN‐γ. This study examines the recognition of the immunodominant T cell epitope on ovalbumin (OVA) following intragastric priming and tolerance. T cells from CY/OVA treated mice and cells from mice injected subcutaneously with OVA in CFA responded well to both OVA and the H2drestricted peptide epitope pOVA323–339releasing GM‐CSF. On the other hand MLN or spleen T cells from tolerized mice which responded to the proteinin vitrodid not recognize the immunodominant determinant. The cells responding from tolerized mice were restricted by the class II MHC so these results show there can be differential recognition of T cell epitopes between oral priming and tolerance.

ISSN:0004-945X    

DOI:10.1038/icb.1994.5

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe balance between cell death and cell proliferation is a significant factor in the growth kinetics of normal and neoplastic tissues. Distinction between the two major forms of cell death, necrosis and apoptosis, is now recognized as important in understanding mechanisms regulating cell survival. A recent approach in the study of apoptosis has been the use of flow cytometry. with some reports indicating that, when stained with propidium iodide (PI), the DNA of apoptotic cells has decreased fluorescence compared with that of viable cells. In this study, we investigated a flow cytometric procedure which used the simultaneous analysis of DNA content and 90° light scatter (90LS). Significant differences in the PI staining pattern and a shift in 90LS were observed when apoptotic death, occurred at different stages of the cell cycle. Importantly, such differences only allowed accurate/quantification of apoptosis when it occurred in G1. While necrosis could be distinguished from apoptosis when examined during its early stages, a similar staining pattern to that found with apoptosis was observed when necrosis was examined during its latter stages. The results indicate that the measurement of DNA staining cannot be exclusively relied upon to detect apoptosis occurring in all models. However it is useful in the investigation of this process when the death occurs in G1, in that the method offers a rapid means for quantification.

ISSN:0004-945X    

DOI:10.1038/icb.1994.6

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe metabolic response of the tumour‐bearing host to methotrexate (MTX) therapy was investigated with particular attention to effects resulting from MTX‐induced anorexia. Biochemical changes in female Dark Agouti rats bearing mammary adenocarcinomas and treated with MTX (0.5 mg/kg. 2 i.m. injections, 24 h apart) were compared with untreated (CON) tumour‐bearing rats, and tumour‐bearing rats pair‐fed (PF) to the MTX group. MTX treatment halted progression of the tumour (tumour 6% of bodyweight) while the tumour burden doubled in the CON and PF groups.A number of biochemical and haematological changes were specific to MTX treatment and did not result from decreased food intake. MTX treatment was associated with significantly decreased plasma calcium, bilirubin, alkaline phosphatase, aspartate aminotransferase and the total white cell count. Decreases in plasma albumin and total protein concentrations were observed in both MTX and PF rats. Other parameters commonly used to assess renal and liver function were not significantly affected by MTX.MTX reversed the hypoglycaemia, hyperketonaemia and hypertriglyceridaemia induced by tumour‐bearing. In contrast, PF rats had an even more pronounced hypoglycaemia and hyperketonaemia than the CON rats. Measurement of glucose uptakein vivowith 2‐deoxy[U‐14C]‐glucose showed that MTX treatment halved the glucose requirement of the tumour (8.2% of bodyweight compared to 12.2% in the control). It is concluded that the potentially adverse effects of MTX treatment on host metabolism are outweighed by the beneficial effects of a reduced metabolic demand resulting from inhibition of tumour progression.

ISSN:0004-945X    

DOI:10.1038/icb.1994.7

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryWM65 is a murine mAb whieh recognizes a novel surface membrane antigen present on leukaemic and normal leucocytes. The present study further investigates the nature of this antigen, especially those features which relate to the possible therapeutic applications of the WM65 antibody. There are 1–3 × 104molecules of this antigen present on normal leucocytes, and the same or greater numbers of antigen molecules are present on a variety of leukaemic cells.In vitrodata showed that the WM65 antibody is internalized following interaction with its antigen on normal leucocytes. The affinity of this antibody was calculated using an FLISA method which required neither labelling of the antibody nor purification of the antigen and the affinity constant was found to be 3 × 107±2 × 107 (mol/L)−1. Further data are presented which suggest that this antigen is a differentiation antigen and an integral membrane protein. Despite the relatively low affinity of the WM65 antibody, a number of characteristics of the antigen suggest the antibody may possibly have therapeutic applications. These characteristics include its cellular distribution, the number of antigen molecules expressed on the cell surface and its ability to internalizein vitro.

ISSN:0004-945X    

DOI:10.1038/icb.1994.8

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryFour thymic epithelial cell lines (TEC) were derived from neonatal CBA and non‐obese diabetic (NOD) mouse thymus. From these cell lines a series of clones were produced by limit dilution and these have remained in stable culture for more than 1 year. Morphological characterization indicates that most cells are stellate with numerous short or long processes and ultrastructural studies show both active and quiescent cells with junctional complexes and bundles of tonofibrils. Immunohistochemical and flow cytometric analyses show that the cells express cytokeratin and appear to label for markers characteristic of cortical epithelial cells. Most clones express Thy‐1, Pgp‐l. ICAM‐1. HSA and B220 antigen, but are negative for LFA‐1. CD2, Mel 14, Fc receptor, Mac‐1, CD4 and CD8. All clones express low to moderate levels of class I MHC but are either negative or extremely low for class II MHC antigen. Most clones secrete IL‐6 and granulocyte‐macrophage‐CSF (GM‐CSF) in vitro, but generally do not produce IL‐2. IL‐3. IL‐4 or IFN‐γ.

ISSN:0004-945X    

DOI:10.1038/icb.1994.9

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryShiga toxin (ST) is a protein toxin ofShigella dysenteriaetype 1, a causative agent of severe diarrhoea and dysentery. In this report we describe the gastrointestinal secretory antibody response of mice following orogastric immunization with ST. Gastrointestinal secretions were sampled by a gastrointestinal lavage technique weekly for 5 weeks after initial immunization. Assay of lavage samples by ELISA showed that mice vaccinated orogastrically with various doses of ST developed gastrointestinal antibody to ST in a dose‐dependent manner. Serum anti‐ST activity developed by 5 weeks after initial immunization. The ability of ST to act as a mucosal immune adjuvant was investigated by coadministration of ST and keyhole limpet haemocyanin. In contrast to cholera toxin, a potent adjuvant, ST did not demonstrate adjuvant activity. The mouse gastrointestinal lavage model could be useful for further analysis of the cellular basis of ST immunogenicity.

ISSN:0004-945X    

DOI:10.1038/icb.1994.10

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY