摘要:

We investigated the role of interleukin 2 (IL‐2), a T cell‐derived lymphokine, in the generation of in vivo cytotoxic T‐cell responses to vaccinia virus. We made use of a recombinant vaccinia virus encoding and expressing the murine IL‐2 gene and recombinant IL‐2 to test the role of IL‐2 in the expression of major histocompatibility complex (MHC) class I determined immune response (Ir) gene defects in the response to vaccinia virus. IL‐2 expressed either by the vaccinia virus vector or exogenous IL‐2 does not alter Ir gene defects nor does IL‐2 under such conditions elevate the cytotoxic T‐cell

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01092.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The main object of this study was to see whether or not chromatin constituents are present in cell membranes. The binding of antinuclear antibodies (ANA) to plasma membranes of leucocytes was studied by using autoantibodies and induced antibodies to different histones and histone peptides, and autoantibodies to double‐stranded DNA (dsDNA) in adsorption–elution experiments. Eluates were subsequently tested for antinuclear antibodies by a solid‐phase ELISA. No ANA activities in the eluates were observed, except when true cross‐reacting ANA were employed in the study. Futhermore, no binding of these antibodies to plasma membranes could be visualized by indirect membrane fluorescence tests. The conclusion of these studies was that freshly isolated viable leucocytes did not carry detectable amounts of ectopic chromatin components at the level of plasma membranes. Thus, it seems fairly unlikely that chromatin autoantibodies in general exert some tissue damage by binding to homologous nuclear antigens associated with plasma membranes

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01093.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Human monocytes and alveolar and peritoneal macrophages were cultured in serum‐free medium with or without endotoxin (ET), agarose beads, or cycloheximide. The cell culture supernatants were collected after various intervals and examined by a monoclonal anti‐S‐protein antibody in Western blot and in a solid‐phase enzyme immunoassay. We found that the phagocytes synthesize and secrete S‐protein. ET stimulation or prolonged incubation of the cells did not favour S‐protein production, which was inhibited by cycloheximide. Agarose stimulation increased the S‐protein level in supernatants from monocyte but not from macrop

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01094.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

We investigated the cytotoxicity of human monocytes mediated by two types of receptors for the Fc portion of IgG, FcγRI and FcγRII. Erythrocytes sensitized with human IgG(EA‐human IgG1) were used to assay FcγRII function, and erythrocytes sensitized with mouse IgG1 (EA‐mouse IgG1) were used to assay FcγRII. Both types of FcγR were observed to mediate antibody‐dependent cell‐mediated cytotoxicity (ADCC), which was Further characterized by using different monoclonal anti‐FcγR antibodies (MoAb) and monomeric IgG. Lysis of EA‐human IgG was inhibited by both monomeric human IgG and mouse IgG2a in a dose‐dependent way, and also by anti‐FcγRI MoAb 10.1. Cytolysis of EA‐mouse IgGI was inhibited by monomeric mouse IgG1 and by two anti‐FcγRII MoAb, IV.3 and CIKM5. Antibodies of the mouse IgG2b isotype affected neither type of ADCC. The effectiveness of cytotoxicity mediated by either of the FcγR was studied by means of targets sensitized with a calibrated number of IgG molecules. At least 20 times more IgG molecules per target cell were necessary to obtain half‐maximal cytotoxicity mediated by FcγRII than for FcγRI‐mediated cytolysis. Furthermore, the previously described polymorphism of FcγRII was also reflected in FcγRII‐dependent cytotoxicity. These studies demonstrate that FcγRII can mediate ADCC, although a higher degree of target cell sensitization i

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01095.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The relationship of velocity of blood flow to density and microanatomical distribution of inflammatory cells in the dermis was studied in 20 human tuberculin tests. Must positive reactions showed maximal blood flow velocities (measured as red blood cell (RBC)flux) at the centre of the reaction, but the two most intense responses showed ‘central relative slowing’(CRS) with higher RBC flux at she periphery. Two of the four clinically negative reactions showed a considerable acceleration of blood flow, but the other two showed no such acceleration. The packing density of lymphocytes/monocytes in the perivascular zone was greater in the stronger positives than in the weaker reactions. The density of cells in the intervening dermis was markedly lower than in the foci: the lesions with CRS had the highest density of cells in the diffuse infiltrate of the reticular dermis. At the centre of the reaction, blood flow velocity was generally related to density of cellular infiltrate, except in those with CRS, which had a disproportionately lower blood flow velocity. The finding that the circulatory adaptation to a delayed hypersensitivity reaction can be inadequate may explain the dermal acidosis previously observed in intense skin test reactions, and may be the underlying mechanism of necrosis in hypersensitive reacti

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01096.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

To assess the role of, and age‐associated alterations in, intraluminal IgG in the intestine, total IgG and subclass distribution in small intestinal perfusates and pilocarpine‐stimulated intestinal secretions were measured under non‐fasting conditions in three groups of BALB/c mice: 2–3, 12–14, and over 24 months old. Total intraluminal IgG and its subclasses (i.e. IgG1, IgG2a, and IgG2b) increased with age. However, the binding capacities of natural intraluminal IgG antibody (Ab) for outer membrane antigen (Ag) from normal habitant bacteria (Escherichia coliandEnterobacter agglomerans) were markedly reduced in the aged lavage samples as compared with such binding in samples from the other two age groups. The striking similarity to serum in the magnitude of the increase of intraluminal IgG and also in the distribution patterns of its subclasses in the small intestinal perfusates from also age groups suggests that the serum is a major source of the IgG. The intraluminal IgG may play some role in humoral immune protection under physiologic conditions of the

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01097.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

We have attempted to develop an in vitro system wherepolyclonalB lymphocyte responses could be induced in ‘antigen‐like’ conditions, that is, where surface immunoglobulin‐dependant binding mediates interaction with a mitogen. Monoclonal anti‐μ and anti‐δ antibodies were covalently bound to lipopolysaccharide (LPS) and these complexes were shown to display mitogenic activity. Polyclonal plaque‐forming‐cell (PFC) responses, however, were diminished in cultures stimulated by anti‐μ‐LPS (but not by anti‐δ‐LPS) indicating that ‘anti‐μ inhibition’ of terminal B‐cell differentiation also applies to ‘specific’ antibody responses. Moreover, the analysis of the functional activity of monoclonal antibodies to major histocompatibility complex (MHC) class II molecules revealed a surprising synergy between low. non‐stimulatory concentrations of anti‐μ‐LPS (but not anti‐SdL‐LPS) with anti‐I‐A antibodies. These responses are T‐cell dependent and synergy with anti‐μ‐LPS conjugates can also be obtained with ‘naturally’ activated CD4+cells isolated from normal donors. A model of molecular and cellular interactions was derived, which accounts for the present findin

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01098.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Recombinant human tumour necrosis factor (rTNF) retained its cytotoxic activity after being fixed with paraformaldehyde to adherent cell monolayers. The cytotoxicity appeared to be mainly due to fixed rTNF and not to any free soluble rTNF that could have leaked out from the lived rTNF cell preparations. The fixed rTNF cell preparations also stimulated the growth of human diploid fibroblasts, under conditions where little growth‐Stimulatory activity was found in suspension. These results indicate that TNF may exert its effect on target cells without internalization, perhaps through a receptor‐mediated process that may alter the levels of a second messenger within the target cells. This signal transduction does not appear to involve cAMP or cGMP, since we were unable to detect significant changes in the levels of these two second messengers in TNF‐exposed WEHI 164 clone 13

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01099.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Natural killer (NK) cell activity and related markers were analysed in childhood acute lymphoblastic leukaemia (ALL). Children with untreated ALL, children with active disease, and children in remission for less than 1 month and undergoing induction therapy had significantly lower NK cell activity in peripheral blood than the control group (P<0.05,P=0.0005. andP0.05). However, their bone marrow cells showed an increased NK cell activity (P<0.0005). Cells positive for the Leu‐7 marker were reduced in the peripheral blood from untreated children (P0.05). However, children in complete remission for more than 3 months had a higher number of bone marrow cells expressing the Leu‐7 (P=0.005) and the Leu‐11b (CD 16) markers (P=0.05) than controls. Stimulation of mononuclear cell suspensions with recombinant alpha interferon and recombinant interleukin 2 were shown to cause a normalization of the NK cell activity in peripheral blood and bo

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01100.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The expression of HLA class II mRNA was investigated in the joints of patients with active rheumatoid arthritis (RA) in order to evaluate patterns of synthesis. Northern hybridization analysis showed that HLA class II gene transcripts in RA joints were of the correct sizes, and subsequent analyses were performed by slot blotting. All active RA samples expressed high levels of HLA‐DR, DP, and DQ mRNA with DP and DQ less than DR. Synovial fluid or membrane cells, chiefly B mixture of T cells and macrophages, were placed in culture, in the absence of any Stimulation. The levels of mRNA remained at a high level in vitro. The half life of HLA‐DR mRNA in joint cells was very brief(∼30 min), indicating that prolonged synthesis was due to re‐stimulation of the cells The effect of lymphokines on HLA class 11 regulation on joint cells was assessed. Gamma interferon was capable of augmenting HLA‐DR to some extent, but paradoxically interleukin 2 at concentrations optimal for stimulating T cells, diminished HLA‐DR

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1989.tb01101.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY