ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02766.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

In mice, a restricted set of the Jh‐proximal Vh genes are preferentially expressed during early ontogeny. Recently, analyses of human Ig cDNA from a fetal liver revealed a restricted set of Vh genes which belong to the VhI, 3, 4, and 6 families. Although the Vh6 and some Vh5 genes are proximal to the Jh region, no Vh5 gene was found in the fetal liver, suggesting that the distance between the Jh genes and some early‐expressed Vh genes may not be the only factor responsible for Vh gene expression during early development. As an initial step in searching for other underlying mechanisms, we characterized two human germline Vh3 genes which belong to the developmentally restricted Vh repertoire, and found that they contain many enhancer‐like sequences which are identical, or highly homologous to, various transcriptional enhancer motifs. Hence, it is conceivable that, in addition to the established positional effects, cis regulatory elements may be important in the programmed expression of some Vh genes during early B‐lymphocyte deve

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02767.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

A number of studies have suggested that lymphocytes producing polyreactive antibodies belong to the CD5+B‐cell subset. In this study we have examined CD5 at the cell surface and mRNA levels in EBV‐driven cord blood and fetal liver clones previously characterized in terms of their antibody specificities. We show that EBV‐immortalized cells can express surface CD5, and that some of the clones not expressing surface CD5 express it at the mRNA level. The complete absence of CD5 mRNA in some polyreactive clones is consistent with the proposition that the production of auto‐antibodies and multispecific antibodies is not restricted to the CD5+B‐ce

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02768.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

In the present study we investigated the effects of inhibitors of glycoprotein processing on cytotoxicity of human large granular lymphocytes (LGL). The incubation of LGL for 36 h with 0.5 μg/ml swainsonine (SW), which is an inhibitor of mannosidase II, resulted in the augmentation of cytotoxicity of LGL against an NK‐resistant colon carcinoma cell line (Colo‐320DM) without increase of binding frequency of LGL to target cells or of cell proliferation. The enhanced cytotoxicity was associated with increased binding of concanavalin A to SW‐treated LGL. The augmentation of cytotoxicity was also seen by 1‐deoxymannojirimycin (1‐DMN), an inhibitor of mannosidase I, but much higher amounts of this agent were needed to get the same level of augmentation as that with SW. Other inhibitors of glycoprotein processing such as castanospermine and 1‐deoxynojirimycin (1‐DN) did not show any augmentative effects on LGL cytotoxicity. The enhancement of cytotoxicity by SW was abolished by the addition of rabbit anti‐human interleukin (IL‐2) antibody to the culture. This result suggests that IL‐2 is involved in the augmentation of cytotoxicity of LGL by SW. The presence of SW in the culture of LGL together with IL‐2 also enhanced LAK generation compared to that with IL‐2 alone. Thus, our results suggest that SW should be recognized as an efficient immunopotentiator and that modulation of carbohydrate moieties elicited by SW may shed further light on the mec

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02769.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Monoclonal antibodies to the human homologue of the bacterial 65 kD heat shock protein (hsp) were used to investigate the tissue distribution of endogenous hsp 65 in normal versus rheumatoid synovial tissue, in subcutaneous nodules of patients with rheumatoid arthritis (RA) and in several instances of non‐rheumatoid inflammation. A strong reactivity of the anti‐hsp antibody was found in the cartilage‐pannus junction in rheumatoid joints and in rheumatoid nodules, but not in normal joints or in normal or inflamed kidney or liver (irreversible graft rejection, chronic glomerulonephritis or primary biliary cirrhosis). The findings provide a new hypothetical explanation for a role of T cells reactive with the 65 kD hsp in the generation of both articular and extra‐articular lesions in chronic rheumatoid ar

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02770.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Ficoll‐separated leucocytes used for phenotyping may be contaminated with erythroblasts or erythrocytes, which can cause problems in cytofluorography, especially if erythroid lineage cells outnumber leucocytes in the preparation. Different means have been described for removing erythroid cells from leucocyte preparations, such as BD‐FACS lysing solution, hypotonic shock and ammonium chloride, but none of these is entirely satisfactory. In my hands all these techniques damaged the leucocytes to a greater or lesser extent and did not adequately eliminate the erythroblasts, sometimes not even the reticulocytes and erythrocytes. To obtain pure leucocyte suspensions, I developed a new technique based on an aggregating antibody (α‐Gly‐A, 733/8F7, from BioCarb, Sweden) directed against glycophorin‐A which is found on the cell surface of erythroid lineage cells. Agglutinated erythroid cells could be removed by filtration or low‐speed centrifugation. With the new technique there was no loss or damage of th

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02771.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

The influence of FK‐506 and ciclosporin (CsA), either alone or in combination, on PHA‐ and alloantigen‐induced human blood lymphocyte transformation was investigated. The concentrations of FK‐506 and CsA required to cause 50% inhibition of mitogen‐induced thymidine incorporation were 1.0 and 200 ng/ml respectively. Evidence of synergistic inhibition of DNA synthesis was obtained when doses of each drug below these concentrations were combined (FK‐506, ≤0.5 ng/ml; CsA ≤50 ng/ml). In contrast, FK‐506 and CsA failed to inhibit PHA‐induced increases in cell size and granularity determined by flow cytometric analysis at 1 and 3 days of culture. Moreover, no significant changes in the expression of the interleukin 2 receptor (IL‐2R; CD25), transferrin receptor (TR; CD7I) or HLA‐DR were observed in terms of percentage positive lymphocytes or mean cell surface membrane fluorescence intensity. In primary mixed lymphocyte cultures, 50% inhibition of thymidine incorporation was obtained with FK‐506 and CsA concentrations of approximately 0.25 and 25 ng/ml respectively. Evidence of synergy was obtained when lower doses of each drug were combined (FK‐506, ≤0.1 ng/ml; CsA ≤2 ng/ml). On their own, these concentrations of CsA were ineffective. In contrast to corresponding PHA‐stimulated cells, FK‐506‐treated alloactivated lymphocytes exhibited reductions in IL‐2R, TR and HLA‐DR antigen expression, which in the cases of IL‐2R and TR were further reduced by combination of FK‐506 with low‐concentration CsA. These data provide further evidence of the potential of combined low‐dosage FK‐506 and CsA for the control of human T‐cell activa

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02772.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

This study introduces a simple, reproducible assay for HLA class I antigen using antibodies against β2‐microglobulin and the heavy chain on HLA. The sandwich technique was named mixed enzyme‐linked immunosorbent assay (MELISA), and was designed for identification of plasma membranes in neutrophil subcellular fractions. The subcellular localization of HLA was identical to that of other plasma membrane markers, [3H]concanavalin A and detergent‐independent alkaline phosphatase, and was unchanged by stimulation of cells by weak and strong secretagogues. In addition to the presence as part of the HLA complex in the plasma membrane uncomplexed β2‐microglobulin is present in the specific granules of neutrophils. However, the release of β2‐microglobulin from intact neutrophils stimulated withformyl‐methionylleucyl‐phenylalanine was much higher than could be explained by exocytosis of specific granules. Subcellular fractionation studies demonstrated that β2‐microglobulin is localized in fractions characterized by latent alkaline phosphatase and released from this novel secretory compartment in response to stimulation withformyl‐methion

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02773.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

We have studied the effects of Fc receptor triggering on the free cytosolic Ca2+concentration, [Ca2+]i, in U937. These cells express two types of IgG Fc receptors, FcγRI and FcγRII. Binding of several anti‐FcγRI and anti‐FcγRII mouse monoclonal antibodies (MoAb) to Quin2‐ or Indo‐I‐loaded U937 cells had no direct effect on [Ca2+]i. After addition of a bridging anti‐mouse Ig antibody however, transient increases in [Ca2+]iwere observed for both types of FcγR. One of the anti‐FcγRII MoAb, CIKM5, was exceptional in that it could induce Ca2+increases in U937 cells by itself. Studies with F(ab′)2fragments of CIK M5 revealed that this MoAb simultaneously binds to FcγRII, via both its Fab and Fc fragments, which might induce cross‐linking of two FcγRII molecules. One anti‐FcγRI MoAb, 197, a mouse (m)IgG2a antibody directed to an epitope outside the IgG‐binding region, remarkably also caused an immediate increase in [Ca2+]i, but only when added to U937 precultured with gamma interferon (IFN‐γ). FcγRI can bind monomeric human IgG as well as mIgG2a, and cross‐linking of cytophilic Ig induced an increase in [Ca2+]i. Our results show that [Ca2+]iincreases can be induced only after cross‐linking of FcγR, either via anti‐FcγR MoAb or via Fc‐FcR interactions. Furthermore, we show that FcγR cross‐linking results in activation of the Ca2+/phosph

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02774.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Removal of the largest single lymphoid organ, the spleen, leads to an increase in severe infections. To prevent this, transplantation of splenic fragments can be performed, which may, however, cause an increase in CD8+lymphocytes in the blood of these patients. This is controversial since in the clinical situation it is often difficult to account for the different age of the patients, the time point after the operation and many other factors known to influence the number of lymphocyte subsets.Using a well‐defined animal model, B, T, CD4+, and CD8+lymphocytes were determined preoperatively in adult rats. Then, either sham splenectomy, splenectomy, or splenic autotrans‐plantation was performed and the animals were followed up for 15 months after the operation.The surgical procedure itself, the site of blood sampling and ageing all influenced the number of lymphocyte subsets profoundly. Furthermore, giving the data as relative or absolute numbers leads to different results.Splenectomy caused lymphocytosis, due to a significant increase in B and CD8+lymphocytes, as did splenic autotransplantation, which indicates that the number of lymphocyte subsets in the blood should not be used to argue in favour of or against splenic autotransplantation.This study demonstrates that the number of lymphocyte subsets in the blood is influenced by many factors and therefore should be determined in a highly standardized fash

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1990.tb02775.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY