摘要:

Sera from 171 consecutive rheumatoid arthritis patients were tested for direct platelet aggregation. Thirty‐three of 146 rheumatoid factor (RF)‐positive sera and 3 of 25 RF‐negative sera gave platelet aggregation, indicating the presence of circulating IgG complexes equal to or greater than 19S. Forty randomly selected sera were analyzed by gel filtrations on Sepharose 4B and Sephadex G‐200 and by sedimentation analysis. IgG complexes, mainly of intermediate sizes, were demonstrated in 54% of sera with RF titers of 40 to 640 and in 80% of sera with an RF titer equal to or greater than 1280. The intermediate complexes could be absorbed on and eluted from cross‐linked human IgG, thus indicating IgG‐RF to be a dominant constituent of th

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01253.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The possible influence of cell membrane dynamics on complement activation and cytolysis was studied. The interaction between membrane‐bound antibodies and complement was investigated by use of purified human C1q protein. The following observations were made: [1] Binding of C1q to cells was proportional to the amount of membrane‐bound antibody. [2]Demonstration of C1q at the cell surface was critically influenced by a prozone effect generated by the interaction between C1q and anti‐C1q antibody. [s] C1q induced pronounced patching of membrane‐bound antibody at 0°C and at 37°C, but its capping effect was weak. [4]C1q seemed to exert an inhibitory action on the disappearance of membrane‐bound antibody. The antibody‐bound C1q disappeared very rapidly from the cell membrane in comparison with the antibody. [5] The cytolytic sensitivity of several cell types differed at different stages of redistribution of membrane‐bound antibody; maximal sensitivity corresponded to a predominantly patchy antibody distribution. Microfluorometry and the isotope antiglobulin method suggested that these changes in cytolytic sensitivity was due neither to differences in the amount of membrane‐bound antibody nor to a different accessibility of membrane‐bound ant

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01254.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The reaction patterns, especially the prozone effect, obtained by the isotope modification of the mixed hemadsorption technique (IMHT) were analyzed with reference to dependence on various factors. The results indicated that the prozone effect in IMHT was related to the relative concentrations of cross‐bridging antibody molecules on indicator and target cells This ratio seemed to have an optimum at which the reactivity was maximal. The existence of such an optimal ratio with regard to the concentrations of cross‐bridging antibody molecules presumably accounts for the previously noted different tendencies to prozone effect of different antigen‐antibody systems The results and indirect evidence suggested that the prozone effect is independent of the antigenic distribution on the cell membrane as influenced by antibody‐mediated redistribution of cell surface antigens. The high sensitivity of IMHT enabled studies of the rate of disappearance of membrane‐bound antibody where this was not possible by othe

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01255.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Tryptic digests of acid‐treated Fc from normal human IgG were separated into four peaks (I to IV) by gel filtration on Sephadex G‐100. Essentially all the material from peak I reacted with staphylococcal protein A. had a molecular weight (MW) of approximately 55,000, and was indistinguishable from intact Fc on electrophoresis and immunodiffusion. Peaks II and III, MW 42,000 and 32,000. respectively, contained both protein A‐reactive and protein A‐nonreactive material, whereas peak IV. MW 12,000, showed no reaction with protein A The protein A‐reactive material from peaks II and III had an intact Fc chain bound to another peptide, from which a part of the C‐terminal sequence had been removed. The protein A‐nonreactive material from peaks II and III lacked antigenic determinant(s) compared to intact Fc and gave fragments with MWs of 16.000 and 18,000. respectively, after reduction, suggesting that these fragments consist of Fc N‐terminal sequences joined by disulfide bonds. It is concluded that, in contrast to interchain interaction, intrachain interactions influence pro

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01256.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

A procedure to assess the cellular adherence displayed by lymphocytes, at the level of the single cell, is described. Adherence is defined as the capacity of a cell to hind acrylic acid polymer beads. 0.5 μm: in size, under standardized conditions These beads were found to adhere readily to lymphocytes that have a high density of surface immunoglobulin Such cells can be distinguished from other leukocytes with the same binding capacity by the extracellular localization of the beads on these cells Furthermore, adherence, as presently defined, is briefly characterized

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01257.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

A calcium‐binding IgG myeloma protein (A. L.) has previously been described It has now been characterized as an IgG1 lambda protein with two independent binding sites for calcium ions. The sites are localized in the Fab regions. Isolated heavy chains showed no unequivocal binding activity, whereas the light chains were active. The apparent intrinsic association constant for protein A.L., as found by equilibrium dialysis, was 104l/mo

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01258.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Cell‐mediated lysis of target monolayers intccted with lymphocytic choriomeningitis virus has previously been shown to be a property of specifically sensitized thymus‐derived lymphocytes (T cells). The cytotoxic potential of individual effector lymphocytes is maximally expressed when infected monolayers are confluent and overlaying immune spleen cells cover less than the total target area. The data presented support the following interpretations [l] Cell‐mediated injury depends on close association between sensitized T cells and infected L cells. [2]Any attachment made is readily reversible. [3] Effector lymphocytes may damage more than one target cell, operating, perhaps, in a rather circumscribed area. [4]Cell death is a ‘one hit’ phenomenon. [5] Cytolysis is a property of individual T cells, there being no obvious requirement for co‐operation between different populations of spleen cells, [6]Substances secreted into the medium at large are neither directly cytotoxic nor capable of sensitizing normal spleen cells. [7] Specific lysis occurs at temperatures ranging from 27°C to 40°C, being maximal at the high

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01259.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The structural pattern of lymphoid tissue in lymphoid thyroiditis was analyzed by thin‐section histology in ten thyroidectomy specimens representing focal and massive thyroiditis. Special attention was devoted to the identification of high‐endo‐thelium postcapillary venules, which were found in eight cases, they were absent only in two of the ‘focal’ cases. These specific vessels were always found immediately outside secondary nodules (‘cortex’), in a narrow zone obviously analogous to the paracortical zone of lymph nodes Thyroiditic tissue thus presented a three‐zonal stratification similar to that seen in lymph nodes, with the medullary zone represented by the lymphoid invasion zone within still preserved thyroid parenchyma. It appeared still more akin, however, to the subepithelial zone of gut‐associated lymphoid tissue. A striking finding in all cases was the predominance of mature plasma cells among the lymphoid cells invading still preserved

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01260.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Peripheral blood lymphocytes from eight patients with chronic lymphocytic leukemia (CLL) were studied. Characterization by different cell surface markers showed low percentages of lymphocytes that bound sheep erythrocytes and had receptors for activated human complement but markedly increased numbers of cells that carried surface immunoglobulins It is concluded that Ig‐bearing lymphocytes are mainly responsible for the lymphocytosis in CLL. The capacity of CLL lymphocytes to lyse51Cr‐labeled chicken erythrocyte in vitro in the presence of phytohemagglutinin (PHA) or antibodies against target cells was reduced A strong correlation was found between the percentages of complement receptor‐bearing lymphocytes and their antibody‐induced cytotoxicity. The ability of CLL lymphocytes to synthetize DNA after stimulation with PHA or pokeweed mitogen (PWM) was reduced The impairment of stimulation was more pronounced at low concentrations of PWM than at high concentrations. This observation is in line with the assumption that low doses of PWM activate mainly bone marrow‐derived lymphocytes and that the normal B‐lymphocyte population is replaced by leukemic c

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01261.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

In mice with meningitis induced by ectromelia virus, the influx of inflammatory cells into cerebrospinal fluid (CSF) was shown to be triggered by an immunologically specific, T cell‐dependent mechanism. These cells were counted, and their cytotoxicity assayed in vitro. Cell numbers reached a peak 6 days after infection and showed specific cytotoxicity for ectromelia‐infected target cells, an effect that reached a peak at day 6 and was retained for at least a further 4 days. Treatment with anti‐thymocyte serum 2 to 3 days before harvest of CSF cells depressed the numbers found and their cytotoxicity, suggesting that they reached the exudate from the

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01262.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY