摘要:

SummaryFundamental questions remain unanswered regarding the effect of the acceptor polypeptide structure on the fine structure of theN‐linked glycan of glycoproteins and conversely, the effect of the glycan structure of IgG on the function and structure of the protein. The construction of myeloma hybrids capable of secreting multiple IgG which differ with regard to the fine structure of theirN‐linked oligosaccharides would be a valuable model for studying these questions. P3X63Ag8 secretes an IgG1which possesses an oligosaccharide at Asn297that differs in fine structure from the analogous glycan of the IgG2bsecreted by Sp2/HLBu. Fusion hybrids of these cells secrete parental IgG1, and to a lesser degree IgG2b, as well as a heterodimeric IgG containing both the γ1and γ2bchains. The oligosaccharide of each chain is identical in structure to the appropriate parental IgG. Such cells allow for the analysis of acceptor properties that influence glycan fine structure, as well as the role of glycan structure on the stability of the IgG.

ISSN:0004-945X    

DOI:10.1038/icb.1991.23

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryEleven different monoclonal antibodies specific for H‐2K‐ and H‐2D‐encoded Class I molecules have been screened to determine Class I epitopes dependent on both carbohydrate and protein structures. Monoclonal antibodies have been identified which bind to carbohydrate‐defined antigens encoded by both the H‐2K and H‐2D gene regions. Sensitivity to glycosidases versus pronase has been used to classify antigens both expressed as cell surface molecules and when prepared as detergent solubilized antigen. Several simple sugars have also been found to act as inhibitors of antibodies which bind to carbohydrate‐defined sites. The genetic control of carbohydrate antigen expression by H‐2K‐ and H‐2D‐linked genes has been verified since a specific antibody does not bind to H‐2Kbor H‐2Dbmolecules encoded by several mutant strains of mice containing single amino acid substitutions in their protein product. All of these data are consistent with Class I antigenic structures being encoded in carbohydrate as well as protein moieties.

ISSN:0004-945X    

DOI:10.1038/icb.1991.24

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe number and frequency of spontaneous and cytokine‐inducible ‘natural’ immunoglobulin‐secreting cells (ISC) were determined in bone marrow (BM). spleen and Peyer's patch (PP),in vitro.Cells were cultured at limiting dilution in the presence or absence of exogenous recombinant cytokines and supernatants then assayed for total immunoglobulin (Ig) and Ig isotype using an ELISA. Most spontaneous ISC were found in the spleen and BM, with fewer in PP. The addition of recombinant interleukin 5 (rIL‐5) promoted a marked increase in both the ISC frequency and the amount of Ig secreted/lSC whereas recombinant IL‐6 (rlL‐6) promoted only a marginal increase. Recombinant IL‐4 (rIL‐4) promoted a marginal increase in ISC frequency only. The isotype profile of ISC was in the order IgM lgG2>lgA>IgG3IgG1.The exposure of cells to 1200 rad of γ‐radiation resulted in decreased numbers of spontaneous ISC in all tissues, but the addition of rlL‐5 or rIL‐6 to the irradiated cells increased both the ISC frequency and Ig secreted. The Ig isotype profile was similar to that of non‐irradiated ISC with a few minor exceptions. This large population of potential cytokine‐inducible ISC could contribute to ‘natural’ Ig secretionin vivo.

ISSN:0004-945X    

DOI:10.1038/icb.1991.25

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryDeoxyspergualin (DOSP) is a new immunosuppressive agent which probably inhibits various functions of monocytes, B cells and T cells. We examined the effects of deoxyspergualin on cellular cytotoxicity, including cytotoxic T lymphocyte (CTL) mediated killer, natural killer (NK) cell and lymphokine activated killer (LAK) cell killing. Deoxyspergualin inhibited cellular cytotoxicity generated by 7 days allo‐antigenic challenge: it also inhibited cell killing if added on day 6 of this 7 day culture period. The drug did not significantly inhibit NK or LAK cell killing. The inhibitory effects of deoxyspergualin, however, were dependent on the serum used in the culture medium. Normal human serum (NHS) was associated with less inhibition than fetal calf serum (FCS). Finally, interleukin 2 (IL‐2) was able to prevent the inhibitory effects of deoxyspergualin on antigen‐specific cytotoxicity.

ISSN:0004-945X    

DOI:10.1038/icb.1991.26

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryOur previous paper reported that it was difficult to induce tolerance using donor specific transfusion (DST) in Lewis rats, while in DA and PVG rats it was possible to induce tolerance using DST. In this paper we investigated the effects of DST in a local graft versus host reaction (GVHR) model using these rat strains. The following results were obtained: (i) DST suppressed the GVHR in the DA rat but not in the Lewis rat; (ii) DST did not suppress GVHR in PVG rat strain, but lymphocytes, prepared from the PVG rats that were tolerant of Lewis heart grafts induced by DST, could suppress the the GVHR; and (iii) in Lewis rats, intrathymic injection of whole blood suppressed the GVHR, suggesting this route of antigen delivery might be effective in prolonging allograft survival. Cardiac allograft survival in this strain was prolonged in some cases after pretreatment with intrathymic donor whole blood. These results suggest the value of the GVHR in the assessment of new protocols to induce allograft tolerance in rats.

ISSN:0004-945X    

DOI:10.1038/icb.1991.27

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe allergenicity of cow's milk whey proteins, purified by high performance liquid chromatography (HPLC), was examined by the radio‐allergosorbent test (RAST) against the sera of children immediately hypersensitive to milk. β‐lactoglobulin and α‐lactalbumin bound specific IgE in the sera of 63% and 75% of these patients respectively. These allergens were tested for cross reactivity with each other by RAST inhibition. Both inhibited the binding of IgE, in the sera of allergic patients, to the other protein. Two possible determinant peptides, one from β‐lactoglobulin and one from α‐lactalbumin, were selected by computer prediction of antigenic sites and synthesized by the fluorenylmethoxycarbonyl (FMOC)‐polyamide method. The peptides were adsorbed to nitrocellulose discs and used in further RAST studies with sera from the allergic children. Both peptides bound specific IgE in the RAST assay.

ISSN:0004-945X    

DOI:10.1038/icb.1991.28

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummarySeveral indices of splenic reactivity were measured daily after ultraviolet (UV) irradiation of mice. Spleen weight increased to a maximum after 5 days. Suppressor cell activity, manifested in various assays, peaked slightly earlier. The ability of passively transferred spleen cells to suppress the induction of contact hypersensitivity (CHS) was maximal after 4 days, as was the production of soluble suppressor factors in culture. The factors were detected by suppression of CHSin vivoand leucocyte adherence inhibition (LAI)in vitro.These assays appeared to detect different factors: an I‐J−factor active in CHS assays and an I‐J+factor active in LAI assays. The latter factor required CD4−, CD8+lymphocytes for its production.

ISSN:0004-945X    

DOI:10.1038/icb.1991.29

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryA new human colon cancer cell line (020588) has been derived by means of a combinedin vitromatrix‐in vivoxenograft technique. The tumour cell line is carcino‐embryonic antigen positive, displays a marker chromosome and proliferates in chemically‐defined scrum‐free culture medium. The chemosensitivity pattern for the tumour cell line was similar to that observed for the parent tumour cells. The novel method used to establish this continuous human tumour cell line may have several advantages over standard techniques.

ISSN:0004-945X    

DOI:10.1038/icb.1991.30

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryVascular leakage of [125I]‐human serum albumin into the skin of sheep was measured in response to intradermal injection of histamine, bradykinin, zymosan‐activated plasma (ZAP), platelet‐activating factor (PAF) and serotonin. Potency of the mediators was PAF>ZAP>bradykinin ∼ histamine>serotonin. Maximal leakage occurred in the first 10 min following injection of bradykinin, histamine and PAF, and for histamine and bradykinin had effectively ceased by 40 min. In contrast, ZAP and serotonin induced relatively constant plasma leakage over the first 40 min following their intradermal injection. Prostaglandins E1and E2enhanced plasma leakage induced by histamine and bradykinin thus confirming the applicability of the two‐mediator hypothesis of vascular leakage to permeability responses in skin of sheep.

ISSN:0004-945X    

DOI:10.1038/icb.1991.31

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

Books review in this article:NEW GENERATION VACCINESEdited by G. C. Woodrow and M. M. LevineMOLECULAR BIOLOGY OF THE MYCOBACTERIAEdited by J. McFaddenIMMUNOTHERAPY AND VACCINESEdited by S. CryzMETHOTREXATE THERAPY AND RHEUMATIC DISEASEEdited by William S. WilkeBIOCOMPATIBILITY: INTERACTIONS OF BIOLOGY AND IMPLANTABLE MATERIALS. VOLUME 1: POLYMERSEdited by F. Silver and C. Doillon

ISSN:0004-945X    

DOI:10.1038/icb.1991.32

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY