bluuebunny/crossref_metadata_2025_split huggingface dataset:
Membrane Ig on human lymphocytes: rate of turnover of IgD and IgM on the surface of human tonsil cells
Authors: Ferrarini M. , Carte G. , Viale Giovanna , Durante Maria L. , Bargellesi A. 
Published: February 2007

AbstractThe turnover of IgM and IgD molecules present on the membrane of human tonsil cells has been studied using immunofluorescence and peroxidase‐catalyzed membrane radioiodination. With the first of the two techniques cells were treated with pronase to remove membrane immunoglobulin (mIg), placed in culture and stained at intervals to check the reappearance of membrane IgD and IgM on the cell membrane. These experiments showed that membrane IgD (in contrast to membrane IgM) are extremely susceptible to proteolysis. Furthermore, cells treated with a concentration of pronase found to be optimal to remove membrane IgM failed to re‐express membrane IgD in vitro. The large majority of tonsil lymphocytes has both membrane IgM and IgD. Due to the different behavior of re‐appearance of the two membrane molecules after treatment with pronase, it was not possible to obtain the simultaneous re‐expression of membrane IgM and IgD by the cells “stripped” with pronase. However, the two molecules were re‐ex‐pressed in vitro by the cells treated with different pronase concentrations with a similar timing, i.e. 50 % or more of the cells re‐expressed membrane IgD and IgM after 8 h in culture. 131I‐radioiodinated membrane IgD and IgM were also released from the cell surface with a. similar timing, the half‐life of permanence on the cell membrane being about 4 h for both molecules. These findings thus indicate that IgM and IgD molecules have a similar turnover and that a cell is capable of placing two different Ig molecules at a time on its surface.
Lymphocyte proliferation in vitro induced by soluble protein antigens. II. Cellular requirements
Authors: Hertel‐Wulff Birgit , Rubin B. 
Published: February 2007

AbstractImmune guinea pig lymph node cells were fractionated on Ig anti‐Ig or HSA anti‐HSA affinity columns or on plastic surface in medium containing carbonyl iron. These techniques selectively removed B lymphocytes, K lymphocytes or adherent cells. The residual cells (Fc receptor‐negative T lymphocytes) responded to soluble antigen in vitro in the same way or even better compared with nonfractionated cells. In addition, there was no indication that antigen‐antibody complexes were superior to antigen in triggering lymph node cells or purified lymph node T lymphocytes into DNA synthesis. The results obtained suggested that memory T lymphocytes can be stimulated by antigen autonomously.
Genetic control of the immune response: ability of antigens of defined amino acid sequence to be recognized by the Ir‐1 gene system
Authors: Seaver Sally S. , Brown A. , Hämmerling G. , McDevitt H. O. 
Published: February 2007

AbstractMice were injected with a series of (T, G)‐A–L [poly (L Tyr, L Glu)‐poly(DL Ala)– poly (L Lys)]‐like compounds with side chains of homogeneous sequences: T‐A–L, GT‐A–L, GGT‐A–L, and TG‐A–L. T‐A–L was not immunogenic. However, T‐A–L was able to bind antibodies to (T, G)‐A–L 509, and this binding could not be blocked by A–L. When complexed with bovine serum albumin, T‐A–L, was immunogenic in both responder and nonresponder strains of mice. GT‐A–L and GGT‐A–L were both immunogenic and elicited the characteristic responder‐nonresponder difference induced by (T, G)‐A–L. TG‐A–L was also immunogenic, but there was considerable overlap in the response of responder and nonresponder strains. On the average, responder mouse serum had a slightly higher antigen‐binding capacity than nonresponder mouse serum. In contrast to antibodies against GGT‐A–L, antibodies against TG‐A–L bound heterologous antigens poorly.These data, along with the results of other investigators, are consistent with the hypothesis that there are multiple Ir‐1 genes which recognize different sequences. The specificity of the Ir‐1 genes is extraordinary. The polypeptides TG‐A–L, TGTG‐A–L and GTTG‐A–L do not appear to be recognized by these genes.
Nature of cells binding anti‐IgE in rats immunized with Nippostrongylus brasiliensis: IgE synthesis in regional nodes and concentration in mucosal mast cells
Authors: Mayrhofer G. , Gowans J. L. , Bazin H. 
Published: February 2007

AbstractThe possibility that IgE is a secretory immunoglobulin has been examined by studying the tissue and cellular localization of IgE in rats infested with the enteric parasite, Nippostrongylus brasiliensis. The lamina propria of the small intestine and the colonic and pulmonary mucosal surfaces contained numerous anti‐IgE‐binding cells, but these were shown to be mast cells and not plasma cells. The major site of IgE synthesis was the regional lymph node of the small intestine, the mesenteric node, which contained large numbers of IgE‐secreting plasma cells. Smaller numbers of IgE‐secreting plasma cells were also found in the axillary node, which drained the site of larvae injection. Peyer's patches, the intrapulmonary bronchial lymphoid tissue and the spleen contained few, if any, IgE‐secreting plasma cells. The significance of the IgE which was readily demonstrated in germinal centers of the mesenteric lymph nodes, the Peyer's patches and the axillary lymph nodes, is not known. In contrast to the infested animals, the lymphoid organs of normal rats rarely contained any IgE‐containing cells. An unexpected observation was that mast cells in mucosal organs appear to contain intracellular IgE, differing in this respect from connective tissue mast cells. Mast cells lying between epithelial cells, the “globule leukocytes”, also appear to contain intracellular IgE, and it is suggested that such cells may be responsible for the presence of IgE in exocrine secretions. This study does not support the suggestion that IgE is a secretory immunoglobulin with a Physiology analogous to that of IgA.
Deletion of hinge region of human myeloma lgG1 molecule (protein LEC) associated with nonexpression of G1m(3) and Km(1,2) allotypes. A possible genetic explanation at the DNA level
Authors: Rivat C. , Rivat Liliane , Ropartz C. , Schiff Claudine , Fougereau M. 
Published: February 2007

AbstractIn this paper we report the structural basis for the nonexpression of G1m(3) and Km(1, 2) allotypes in an IgG1 (K) human myeloma protein (protein LEC). Heavy and light chains spontaneously dissociate in sodium dodecyl sulfate polyacrylamide gels. Light chains appear to be covalently S‐S bonded. Analysis of cysteine‐containing peptides shows that the heavy chain of the IgG protein LEC has a deletion of residues 21 6‐230, thus encompassing the entire hinge region. An arginine residue, characteristic of the G1m(3) marker is present at position 214. An alanine at position 153 and a leucine at position 191 of the light chain, characteristic of the Km (1, 2) allotypes, are present. It is likely that the double Km and Gm lack of expression is the result of the deletion. The genetic implications of the sequence of this protein are discussed.
Immunological properties of murine thymus‐dependent lymphocyte surface glycoproteins
Authors: Trowbridge I. S. , Mazauskas Catherine 
Published: February 2007

AbstractThe immunological properties of two murine thymus‐dependent (T) lymphocyte surface glycoproteins, T200 and T25, were investigated. T200 is a lymphocyte‐specific antigen with a high degree of species specificity. It shares antigenic determinants with molecules present on thymus‐independent (B) lymphocytes.T25 has antigenic determinants which cross‐react with antigens on mouse brain, rat thymocytes and rat brain. An antiserum against a purified rat brain glycoprotein which carries Thy‐1.1 reacts with T25. Absorption of this antiserum with BALB/c thymocytes or brain homogenate produces a Thy‐1.1 ‐specific serum which reacts with T25 from AKR/J thymocytes but not with T25 from AKR/Cum thymocytes. These results confirm that T25 is the molecule on the surface of mouse T cells which carries the Thy‐1 antigen. T25 also carries antigenic determinants, recognized by anti‐thymocyte serum (ATS), which were found on secondary mouse embryo fibroblasts and untransformed fibroblast cell lines but which were not detected on fibroblast cell lines transformed with murine sarcoma virus (MSV) or with Simian virus 40 (SV40).A third T lymphocyte‐specific antigen with an apparent mol. wt. of 35 000 Daltons, that is recognized by ATS and is expressed on thymocytes and spleen cells, was detected. In contrast to T25 this molecule is not present on brain nor on BW5147, a T cell lymphoma.
HLA‐B specificities and w4, w6 specificities are on the same polypeptide
Authors: Ayres Janet , Cresswell P. 
Published: February 2007

AbstractThe human alloantigenic specificities w4 and w6, which are products of a diallelic system genetically associated with the HLA‐B locus, have been solubilized by papain digestion of membranes from the lymphoblastoid cell line, RPMI 4265. The w4 and w6 specificities copurified with the HLA‐B locus products, HLA‐B7 and HLA‐B12. Sequential immunoprecipitation experiments were performed using alloantisera to HLA‐B7, HLA‐B12, w4 and w6, and a purified HLA‐B7, B12, w4, w6 antigen pool labeled with 125I‐Bolton‐Hunter reagent. These experiments demonstrated directly that HLA‐B7 and w6, which are genetically associated with each other, are different antigenic determinants on the same molecule, while HLA‐B12 and w4, also genetically associated, are distinct antigenic determinants on a second molecule. Arguments are presented which suggest that the HLA‐B determinants and w4, w6 determinants are in fact on the same polypeptide, and the genetic implications of the findings are discussed.
Malarial immunodepression in vitro: adherent spleen cells are functionally defective as accessory cells in the response to horse erythrocytes
Authors: Warren H. S. , Weidanz W. P. 
Published: February 2007

AbstractThe basis for the depressed response of malarial infected mice to horse red blood cells (HRBC) has been studied in vitro. Results presented show that the adherent spleen cells from infected mice (a) are defective in their ability to allow nonadherent spleen cells of both normal and infected mice to respond to HRBC whereas a response does occur with adherent spleen cells from normal mice (b) do not suppress the response of unfractionated spleen cells from normal mice to HRBC (c) contain phagocytic cells as measured by the uptake of neutral red in numbers which are of the same order of magnitude as in adherent spleen cells from normal mice, but which are unable to take up HRBC. We conclude that a splenic adherent cell, probably the macrophage, is functionally defective as an accessory cell in the response to HRBC of mice infected with Plasmodium berghei yoelii.
Antigenic specificity of the cytolytic T lymphocyte (CTL) response to murine sarcoma virus‐induced tumors. I. Preferential reactivity of in vitro generated secondary CTL with syngeneic tumor cells
Authors: Plats F. , Cerottini J.‐C. , Jongeneel V. , Brunnera K. T. 
Published: February 2007

AbstractIncubation of spleen cells from mice having rejected a Moloney sarcoma virus (MSV)‐induced tumor with syngeneic irradiated lymphoma or sarcoma cells bearing MSV‐associated antigens in secondary mixed leukocyte‐tumor cell cultures (MLTC) resulted in the generation of highly active cytolytic T lymphocytes (CTL) specifically directed against syngeneic target cells bearing MSV‐associated antigens. When MSV‐immune spleen cells from C57BL/6 (H‐2b) and BALB/c (H‐2d) mice were compared with respect to their ability to generate CTL in syngeneic secondary MLTC, it was found that both lymphoid cell populations were equally able to mount an anamnestic CTL response to MSV‐associated antigens as assessed by a short‐term 51Cr release assay. However, quantitative analysis of the activity of both CTL populations on either H‐2b or H‐2d tumor cells indicated that target cells sharing the same major histocompatibility complex (MHC) as the effector cells were lysed 10‐ to 100‐fold more efficiently than allogeneic target cells. As suggested by the results of inhibition experiments using mixtures of 51Cr‐labeled and unlabeled target cells, preferential lysis of syngeneic versus allogeneic tumor cells might be related to the establishment of effective adhesions between the former and CTL.Direct evidence for the role of MHC in determining the antigenic specificity of CTL directed against MSV‐associated antigens was provided by results obtained using MSV‐immune spleen cells from congenic resistant mice. Furthermore, studies of the response of F1 (H‐2b/d) hybrid mice showed that stimulation of immune spleen cells with tumor cells from one parental strain or the other in secondary MLTC resulted in the generation of CTL capable of lysing tumor target cells of the same parental strain as the stimulating cells, but not of the other. The results thus suggested the presence of two sets of CTL precursor cells in F1 MSV‐immune spleens, each set responding exclusively to tumor antigens associated with only one of the two parental phenotypes.
Lack of effect of thymectomy on spontaneous recovery from tolerance to levan
Authors: Howard J. G. , Courtenay Barbara M. , Hale Christine 
Published: February 2007

AbstractAdult CBA mice were made tolerant with 1 mg levan and tested subsequently for spontaneous recovery by plaque‐forming cell assay in response to immunizing challenge. Weakening of tolerance was first detectable only after 100 days, while return to full normal responsiveness required 400 days. Thymectomy 2 weeks prior to tolerization neither retarded nor diminished the recovery process. Loss of tolerance which had been induced by 1 mg dextran B512 was much slower in onset (> 250 days), yet not delayed by thymectomy (full recovery was not followed).These findings in relation to other considerations imply that associative recognition by T cells is not required for B cell responses to these “thymus‐independent” antigens.
Immunoglobulin‐like messenger RNA in a mouse T cell lymphoma
Authors: Babbitts T. H. , Forster A. , Smith M. , Gillam S. 
Published: February 2007

AbstractRNA‐driven complementary DNA (cDNA) hybridization experiments have been carried out in order to detect complementary sequences in RNA prepared from a mouse T cell lymphoma line (EL4). In conditions where efficient hybridization of L‐chain cDNA with homologous P3 myeloma mRNA was observed, poor hybridization was observed with EL4 mRNA unless a low criterion of hybrid formation was employed (i.e. hydroxyapatite fractionation). The hybrid formed between EL4 mRNA and L‐chain cDNA was found to melt about 5 °C below the homologous hybrid indicating that the sequence detected in EL4 mRNA is similar but not identical with the P3 mRNA sequence. However, a similar sequence was detectable in a Cλ‐producing myeloma cell line but in this line the concentration of the sequence was found to be an order of magnitude lower than in EL4 cells.
Induction and characterization of “autologous” anti‐idiotypic antibodies
Authors: Cosenza H. , Augustin A. , Julius M. H. 
Published: February 2007

AbstractUpon immunization with phosphorylcholine (PC), conventional BALB/c mice produce anti‐PC antibodies bearing predominantly the idiotype characteristic of the BALB/c PC‐binding myeloma protein TEPC 15 (T1 5). To investigate whether BALB/c mice are able to produce antibodies to the autologous T15 idiotype, conventional (T1 5‐positive) and neonatally suppressed (T1 5‐negative) BALB/c mice were immunized with purified T15 myeloma protein. Both groups of mice produced IgG antibodies specific for the T1 5 idiotype. However, anti‐T 15 antibodies were more readily induced in neonatally suppressed mice which in turn produced higher anti‐T15 titers than conventional mice. Such “autologous” anti‐T 15 antibodies are able to (a) change the idiotypic pattern of the anti‐PC response of conventional BALB/c mice in situ and, (b) inhibit the induction of an anti‐PC response in vitro by spleen cells from T15‐positive but not T15‐negative BALB/c mice. Thus, BALB/c mice are capable of producing anti‐T 15 antibodies upon immunization with an isologous myeloma protein which bears the autologous T1 5 idiotype. We suggest that idiotypes should not be strictly considered as “self‐antigens” since the dramatic increase in their concentration, subsequent to antigen stimulation, might confer upon them immunogenic properties not shared by self‐antigens.
Reducèd in vitro response to concanavalin A and lipopolysaccharide in senescent mice: a function of reduced number of responding cells
Authors: Abraham Carmella , Tal Y. , Gershon Harriet 
Published: February 2007

AbstractStudies of the cell cycle of cells responding to Con A and to LPS from 12 and 28‐month‐old mice demonstrate that the generation time of individual proliferating cells does not alter with age. Nor does it differ for the B cells responding to LPS or the T cells responding to Con A. These studies also demonstrate that the proliferating cells from senescent mice are equally capable of repeated cell divisions as are the cells from the 1‐year‐old adult mouse. It is concluded that the defect in senescent mice which leads to a reduced in vitro response to the polyclonal mitogens LPS and Con A is a reduction in the number of responding cells and not an alteration in the capacity of those cells which do respond to divide.The proliferative capacity of spleen cells from C57BL/6J female mice of various ages (3‐28 months) to the polyclonal mitogens concanavalin A (ConA) and lipopolysaccharide (LPS) was examined. It was found that both the T and B cell population of the spleen demonstrate an age‐related decrease in their capacity to respond in vitro. Peak responses to both mitogens occurs at about 1 year of age. This age‐related reduction in response is expressed in the degree of incorporation of [3H]thymidine into DNA, the total number of cells generated in vitro, the number of labeled cells per culture and the number of blast cells per culture. The day of peak response in vitro does not change with age.
Suppressor cell induction in vitro
Authors: Kontiainen Sirkka , Feldmann Marc 
Published: February 2007

AbstractAntigen‐specific suppressor T cells induced in vitro release, after a further period of culture in vitro with antigen factors into the supernatant which have suppressor activity. These suppressor factors (SF) have the same antigen specificity as the suppressor cells (SC). SF only works on the early phase of thymus‐dependent responses in cultures. SF inhibits thymusdependent IgM, but not thymusindependent IgM responses in vitro. SF is destroyed by proteolytic enzymes, and inactivated at 80°C for 30 min. The release of SF from SC is dependent on the presence of antigen and metabo‐lically active cells.
Characterization of B cell subpopulations by velocity sedimentation, surface la antigens and immune function
Authors: Press Joan L. , Strober S. , Klinman N. R. 
Published: February 2007

AbstractAn in vitro splenic focus assay for B cell cloning was used to analyze the responses of primary and secondary B cells obtained after fractionation on (1 × g) velocity sedimentation gradients. When nonimmune adult bone marrow cells are fractionated, the small cell (slowly sedimenting) fraction contains the majority of primary B cells specific for the 2,4‐dinitrophenyl determinant (DNP). When nonimmune adult spleen cells are fractionated, all of the cell fractions contain B cells specific for DNP or for fluorescein (FL), and the large and medium cell fractions contain approximately 50 % of the activity. There is a differential expression of IgM vs. IgG1 anti‐hapten monoclonal antibody, in that the majority of primary splenic B cells which give rise to clones producing only IgM antibody are found predominantly in the large and medium cell fractions. All of the cell fractions contain B cells which can generate clones producing both IgM and IgG1, or only IgG1 antibody. Ia‐“negative” B cells which give rise to clones producing only IgM antibody are found in the large and medium cell fractions, whereas all the cell fractions contain la‐positive B cells. When secondary spleen cells are fractionated, all of the cell fractions contain secondary B cell activity. The large and medium cell fractions contain half of the DNP‐specific secondary B cells, whereas the medium and small cell fractions contain more secondary B cells specific for FL or hemocyanin. The large and medium cell fractions of secondary spleen cells are not enriched for B cells giving rise to clones producing only IgM antibody.
Increase in T cell mitogen responsiveness in rat thymocytes by thymic epithelial culture supernatant
Authors: Kruisbeek Ada M. , Kröse Tonny C. J. M. , Zijlstra Jelly J. 
Published: February 2007

AbstractSupernatants from rat thymic epithelial cultures (TES) increased [14C]thymidine incorporation into rat thymocytes stimulated with phytohemagglutinin (PHA) or concanavalin A, whereas supernatants from nonthymic control tissue cultures had no effect. It was demonstrated that the increased mitogen responsiveness was at least partially due to an increase in the number of responsive cells. Furthermore, our data suggest that the target cell for TES resides among the cortisone‐sensitive population of thymocytes. The continuous presence of TES provided the best conditions for enhancement of mitogen stimulation. The addition of TES had very little effect on mitogen‐stimulated spleen and lymph node lymphocyte cultures.The data suggest that, in the presence of TES, a cortisone‐sensitive, PHA‐nonre‐sponsive subpopulation of rat thymocytes is induced to respond to PHA.
Mechanisms of B cell tolerance
Authors: Abbas A. K. , Klaus G. G. B. , Mcelroy P. J. 
Published: February 2007

AbstractExposure of 2, 4‐dinitrophenyl (DNP)‐hemocyanin‐primed spleen cells to DNP‐conjugated pneumococcal polysaccharide (DNP‐S3) in vivo or in vitro renders such cells unresponsive to DNP‐hemocyanin challenge following adoptive transfer. The unresponsiveness is hapten‐specific, independent of the presence of T cells and adherent cells, and not due to either toxic effect of S3 or carry‐over of tolerogenic amounts of cell‐bound DNP‐S3, and thus presumably represents a model of B cell tolerance. The degree of suppression induced depends upon the dose of the tolerogen and most strikingly on the duration of exposure of cells to the tolerogen. Thus 2 to 6 h exposure to DNP‐S3 has an insignificant effect on anti‐DNP responses, while 24 and 48 h exposures in vitro and in vivo are highly suppressive. Such a dynamic process of tolerance induction suggests a “multiple hit” phenomenon, implying the generation of suppressive signals by repeated cycles of tolerogen‐receptor interactions. The process can be interrupted by removal of extracellular DNP‐S3, although this does not reverse the unresponsiveness that has already been induced.