ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01226.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The generation of antibody diversity can be discussed at two levels: genotype and phenotype. The genetic question is, does the germ line genome contain all antibody genes, or are some created (by mutation) during the life of the individual? An equally important question at the level of phenotype is, when is immune competence expressed during development of an individual, and, particularly, does antigen stimulation increase the repertoire of competent cells? In this short article we will concentrate on the last question, after first listing reasons why we prefer somatic mutation to germ line theories at the genetic level. We will draw attention to some of the considerable body of indirect evidence that supports antigen‐generated diversity and briefly discuss experiments that can directly test whether entirely new kinds of immunocompetent cells appear during the course of an immune respons

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01227.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The cleavage of pooled human IgG and IgG1, IgG2, and IgG3 myeloma proteins with α‐chymotrypsin has been studied. The products of digestion were analyzed by starch gel electrophoresis and fractionated by gel filtration, In addition to low molecular weight peptides an electrophoretically fast fragment from the Cγ3 homology region (ctFc') was detected in all cases. Pooled IgG, IgG1, and IgG3 proteins fielded appreciable amounts of an Fab‐like fragment. Finally, various high molecular weight fragments were released that appeared to resemble recently described fragments produced by papain. These were Fab/c‐like fragments from pooled IgG and IgG1, F(ab)2‐like fragments from IgG2, and Fch‐like fragment

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01228.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Precultivated autologous macrophages enhanced the early PPD‐induced blastogenic response of tuberculin‐sensitive lymphocytes. This effect was not caused by a diffusible macrophage product. Macrophages exposed to PPD and subsequently washed caused as high a response as did PPD in cultures without precultivated macrophages. Sensitive macrophages were not able to induce nonsensitive lymphocytes to respond to PPD. Precultivated macrophages from tuberculin‐negative patients with sarcoidosis enhanced the PPD‐induced transformation of sensitive lymphocytes, as did autologous macrophages Cord blood‐derived macrophages were significantly less

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01229.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The cytotoxicity of human peripheral blood lymphocytes against chicken erythrocytes sensitized by rabbit antibodies was inhibited by human immunoglobulin and immunoglobulin fragments. Myeloma proteins isolated in dimeric state or aggregated by heat treatment inhibited better than the corresponding monomeric proteins. Strong inhibition was observed with IgG1 and IgG3, and with IgG2after aggregation, while IgG4inhibited very little. No inhibition was found with IgM, IgA. IgD and IgE. The F(ab')2. and Fab fragments of IgG inhibited poorly or not at all. While‐ considerable inhibition was observed with the Fc fragment, the pFc’ fragment, which roughly corresponds to the C‐terminal half of the Fc portion, showed little inhibitory capacity. A fragment isolated from IgG3, containing an extension of the N‐terminal part of Fc (the Fch fragment), was an even better inhibitor than tin Fc fragment. The inhibitory capacity of the Fch and Fc fragments was greatly diminished following partial reduction and alkylation On the basis of the inhibitory pattern of IgG fragments, it is suggested that the region on the immunoglobulin molecule involved in binding to the Fc receptor of the effector lymphocytic cell may be located within the CH2

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01230.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Nude, putatively athymic mice injected with a single high dose of sheep erythrocytes fail to respond by producing splenic plaque‐forming cells when injected 1 week later with T cells plus sheep erythrocytes. Spleen cells from such mice are defective in their capacity to transfer at least an IgG plaque‐forming cell response to sheep erythrocytes when injected into irradiated recipients together with T cells. The results suggest that T‐cell‐independent antibody production in nude mice is shortly followed by a defect in B‐cell responsiveness. A recent hypothesis, which ascribes a protective function of T cells for B cells of high antigen‐binding capacity, is furthe

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01231.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Immunoelectrophoresis of serum Sö showed an abnormal albumin line extended cathodically into the β‐region and a thick IgM line extended anodically into the α2‐region. These abnormalities were caused by noncovalent binding of albumin to a monoclonal IgM and continuous dissociation of the complex during electrophoresis. The complex formation was immunologically specific in that human, hut not bovine, albumin combined with IgM Sö. The combining sites on IgM ‐were localised to the Fabμ fragment. Albumin was probably univalent in the reaction, since monomerk human serum albumin combined but did not precipitate with IgM Sö, whereas soluble aggregates of human serum albumin precipitated

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01232.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The kinetics of development of anti‐hapten‐Kactive T and B cells in groups of mice immunized against different dotes of two hapten‐protein conjugates was measured at different times. after a primary immunization with a single batch of conjugated sheep erythrocytes. In addition, the affinity of the receptors on the specific antigen‐reactive cells was determined. Immunogenic doses of NNP‐HGG varied from 40μg to 2mg, whereas 0.4μg even with adjuvant were nonimmunogenic .The affinity of antibodies secreted by single cells was measured by a modification of the local hemolysis in‐gel assay with different concentrations of free hapten incorporated in the .agar. which showed a marked shift in affinity for i.PFC in contrast to d.PFC with time The affinityof receptor bearing antigen‐binding cells of both T and B origin was also Studied by a hapten inhibition assay With the aid of specific antisera against T and B spleen lymphoid cells. pure population of T or B cells could be obtained from spleens of mice immunizedwith different hapten‐protein conjugates .The binding strength of antigen‐binding B cells increased with time after immunization, whereas that of antigen‐binding T cells did not. The results are discussed in the light of recent studies on the structure

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01233.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

Antibody activity in feces was investigated by testing for agglutinins to rabbit erythrocytes Extracts of freeze‐dried feces from 13 of 14 infants and children agglutinated the rabbit erythrocytes, as did the sera from ill all these individuals. Feces from I‐month‐old infants gave relatively high titres, whereas sera gave loss titres compared with what was found in older children. Thus, the intestinal agglutinins seemed to be produced independently of those in serum. The fecal agglutinins correlated well with the concentration of IgA in feces and were inhibited with antiseri In IgA. indicating that IgA in feces was mainly responsible for the agglutination Results of preparative ultracentrifugation and gel filtration as well as immunization studies were in line with this There is thus evidence that only IgA retains its, activity in the gut. even when IgG and IgM are present in feces. Since agglutinins to rabbit erythrocytes in serum are mainly confined to IgG and IgM, this activity in feces seems to be a useful market for locally produced intestina

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01234.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

51Cr‐ labelled chicken erythrocytes (E) were treated with human and C7 to form , susceptible to lysis by the terminal complement components C8 and C9 ('reactive lysis') Addition of purified and extensively washed human blood lymphocytes, but not of erythrocytes, to resulted in a similar but cell‐mediated reactive lysis. Contamination of the effector cell preparations with plasma was excluded. The reaction does not require living effector cells. Its dependency on C8 was proved by inhibition with rabbit anti‐human C8 as well as with its F(ab')2fragments. Although terminal complement components may be of importance for cell‐mediated lysis of complement‐carrying target cell, no effector role could be assigned to them in antibody‐dependent lymphocyte mediated lysis Thus, lysis of antibody‐coated chicken erythrocytes in the absence of added complement by purified human lymphocytes was not inhibited by the F(ab')2fragme

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1974.tb01235.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY