bluuebunny/crossref_metadata_2025_split huggingface dataset:
A second signal for T cell mitogenesis provided by monoclonal antibodies CD45 (T200)
Authors: Martorell Jaime , Vilella Ramón , Borche Luis , Rojo Isabel , Vives Jordi 
Published: March 2007

AbstractThe induction of T cell mitogenesis through CD3 is a complex process that requires at least two signals. The first one can be provided by Sepharose‐bound CD3. The second one is normally provided by monocytes. The signal provided by Sepharose‐bound CD3 is unable by itself to induce mitogenesis in monocyte highly depleted cells (MHDC).We describe here that the monoclonal antibody (mAb) 72‐5D3 belonging to CD45 (T200), which was not mitogenic by itself, could replace monocytes when MHDC were activated by Sepharose‐bound CD3. That is to say, in the absence of monocytes, mAb 72‐5D3 gave a second signal necessary for T cell proliferation. Using eleven anti‐CD45 mAb from other investigators we show that this effect is not a peculiar characteristic of 72‐5D3 mAb. The effect of the mAb 72‐5D3 was only effective in CD4‐positive cells and was not observed when MHDC were activated with either soluble CD3 or concanavalin A.As both phorbol myristate acetate and mAb 72‐5D3 can replace monocytes, a comparative study of their effects was undertaken. Phorbol myristate acetate but not mAb 72‐5D3 induced proliferation of MHDC when recombinant interleukin 2 (rIL2) was added. On the other hand mAb 72‐5D3 induced IL2 production in MHDC activated by Sepharose‐bound CD3 and increased the IL2 production in Sepharose‐bound CD3‐activated peripheral blood mononuclear cells.In conclusion, data presented in this report indicate that the T200 molecule could be involved in T cell proliferation by giving a signal that induces the production of IL 2 and bypasses the necessity of monocytes.
The human mononuclear phagocyte high‐affinity Fc receptor, FcRI, defined by a monoclonal antibody, 10.1
Authors: Dougherty Graeme J. , Selvendran Yogi , Murdoch Sarah , Palmer David G. , Hogg Nancy 
Published: March 2007

AbstractThe properties of the mononuclear phagocyte (Mph) high‐affinity Fc receptor, FcRI, were investigated using a novel monoclonal antibody (mAb) designated 10.1. This receptor was shown to be a protein of 71 kDa, presented chiefly on monocytes and the myeloid cell lines U937 and HL60. mAb 10.1 inhibited the binding to Mph of erythrocytes opsonized with rabbit IgG or human IgG3. It also blocked T cell proliferation induced by murine CD3 mAb of the IgG2a but not the IgG1 subclass. These results suggest that rabbit IgG, human IgG3 and murine IgG2a all bind to FcRI in a similar manner and that mAb 10.1 reacts with an epitope on FcRI near to the binding site for the Fc region of IgG. In addition, although it is well known that FcRI has a high affinity for both monomeric human IgG1 and IgG3, we show in this study that while erythrocytes opsonized with human IgG3 bind to Mph, equivalent cells opsonized with IgG1 surprisingly do not. These results define further the nature of the constraints on the interaction between Mph FcRI and particular IgGs.
Relationships between B‐lineage lymphocytes and stromal cells in long‐term bone marrow cultures
Authors: Witte Pamela L. , Robinson Margaret , Henley Anna , Low Martin G. , Stiers David L. , Perkins Steve , Fleischman Roger A. , Kincade Paul W. 
Published: March 2007

AbstractIn long‐term culture of mouse bone marrow, the growth and differentiation of B‐lineage lymphocytes depends on interaction with adherent cells or their products. The objectives of these studies were to characterize the types of cells present in the supporting adherent layer as well as the physical relationships of these cells with lymphocytes. With an extensive panel of antibodies against hemopoietic and lymphocyte antigens, two discrete nonlymphoid populations were identified: macrophages and undefined, large cells which we termed “stromal cells”. Lymphocyte clusters grew in actual contact with the latter cells only. Stromal cells lacked expression of most hemopoietic antigens, including the common leukocyte antigen, J11d, heat stable antigen (M1/69), Thy‐1 and BP1. Antigens expressed by stromal cells were detected by AA4.1, our 94.2 antibody, and antibody to the Forsmann antigen, but the most distinguishing characteristics of the lymphocyte‐binding stromal cells were production of basement membrane components, laminin and collagen IV, and the extremely low uptake of acetylated low density lipoprotein (LDL). Using acetylated LDL uptake as a sorting criterion, the lymphocyte‐binding stromal cells were separated from the macrophages, recultured and shown to support lymphocyte proliferation. We found the binding between stromal cells and lymphocytes to be highly selective and dependent on divalent cations; hence, specialized adhesion mechanisms may have a role in B cell development. Moreover, our studies suggest that phosphatidylinositolanchored cell surface molecules may be involved in this adhesion. Our findings demonstrate the possibility that a single cell type provides physical support and proliferation stimuli for early B‐lineage cells. This accessory cell is not a macrophage; rather, it has features of an endothelial or epithelial cell.
Two monoclonal anti‐CD3 antibodies can induce different events in human T lymphocyte activation
Authors: Roosnek Eddy E. , van Lier René A. , Aarden Lucien A. 
Published: March 2007

AbstractTwo monoclonal antibodies, WT32 and CLB‐T3/4.2a, directed against the CD3 complex were used to study the mechanism of activation of human peripheral T lymphocytes. WT32, a mouse monoclonal IgG2a antibody with a low avidity (≫ OKT3) for the CD3 complex, effectively induces mitogenesis of purified T lymphocytes when used in the 1 ng‐10 μg range in the presence of monocytes or recombinant interleukin 2 (IL 2). In contrast, CLB‐T3/4.2a, a mouse monoclonal antibody of the same isotype with a high avidity (< OKT3) for the CD3 complex, induces IL 2 receptor expression and IL 2 responsiveness only at very low concentrations (< 5 ng/ml), yet in the presence of monocytes this antibody induces proliferation within a similar dose range as WT32. Apparently, in the absence of accessory cells which can cross‐link the antibody CD3 complexes, the binding properties (avidity) of an antibody and thereby the number of receptors that are occupied are important parameters for induction of IL 2 responsiveness. Furthermore, we show that Ca2+ mobilization only occurs when the cells are stimulated by saturating amounts of antibody, so that, when the conditions are optimal for the induction of IL 2 responsiveness, no Ca2+ mobilization will be detected.
Recognition by major histocompatibility complex class I‐restricted cytolytic T lymphocytes of cells expressing vaccinia‐encoded viral and class I proteins
Authors: Andrew Marion E. , Coupar Barbara E. H. , Boyle David B. , Blanden Robert V. 
Published: March 2007

AbstractTarget cells expressing influenza virus hemagglutinin (HA) could be recognized by cytotoxic T lymphocytes (CTL) in conjunction with the murine major histocompatibility complex class I antigen, H‐2Kd, when both antigens were encoded by recombinant vaccinia virus. This recognition occurred if HA and H‐2Kd were encoded by separate vaccinia viruses following dual infection of target cells or if HA and H‐2Kd were encoded by a single recombinant virus. In contrast, target cells expressing nucleoprotein (NP) were only recognized by H‐2Kd‐restricted CTL if both NP and H‐2Kd were encoded by the same vaccinia virus. These results show that the requirements for association of H‐2Kd with different viral antigens derived from HA or NP can vary. Possible factors contributing to this difference are discussed.
CD43 monoclonal antibodies recognize the large sialoglycoprotein of human leukocytes
Authors: Borche Luis , Lozano Francisco , Vilella Ramon , Vives Jordi 
Published: March 2007

AbstractIn this study data are presented indicating that the molecule identified by the recently described CD43 cluster of monoclonal antibodies (mAb; Oxford, 1986) is the human analogue to the one originally described in rat as leukocyte sialoglycoprotein (LSGP). This conclusion is based on several criteria. Both molecular mass (105 kDa) and cellular distribution are similar to the antigens previously described in the rat with the mAb W3/13 and subsequently in humans with L10 mAb. Sialidase treatment of the molecule immunoprecipitated by 84‐3C1 mAb (CD43) resulted in a decreased electrophoretic mobility on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. L10 mAb inhibited the binding of 84‐3C1 mAb to the cell membrane suggesting that both mAb recognized the same molecule.Moreover, the presence in the CD3−4−8− thymic populations of the sialidase‐sensitive epitope recognized by mAb 84‐3C1 suggests that there is no simple correlation between the thymic maturation and the degree of sialylation.
In vitro production of human interleukin lα and interleukin 1β by peripheral blood mononuclear cells examined by sensitive sandwich enzyme immunoassay
Authors: Tanaka Koichiro , Ishikawa Eiji , Ohmoto Yasukazu , Hirai Yoshikatsu 
Published: March 2007

AbstractThe in vitro production of human interleukin 1α (hIL 1α) and interleukin 1β (hIL 1β) by peripheral blood mononuclear cells was examined by sensitive sandwich enzyme immunoassays which could discriminate hIL 1α and hIL 1β without cross‐reaction with human IL2. In culture supernatants of mononuclear cells, two components were detected by sandwich enzyme immunoassay for hIL 1α or hIL 1β. The molecular weight of one component was shown to be equal to that of recombinant hIL 1α or hIL 1β by gel filtration. The elution volume of the other component corresponded to a molecular weight of about 30000. The sum of the two components for both hIL 1α and hIL 1β in culture supernatants of peripheral blood mononuclear cells from healthy subjects increased 1.7 to 38‐fold by Escherichia coli lipopolysaccharide. The sum of the two components for hIL 1β was 13 to 97‐fold larger than that for hIL 1α.
Idiotype switching of CD4‐specific monoclonal antibodies can prolong the therapeutic effectiveness in spite of host anti‐mouse IgG antibodies
Authors: Jonker Margreet , Den Brok Jan H. A. M. 
Published: March 2007

AbstractImmunotherapy using murine monoclonal antibodies (mAb) is limited by the host anti‐mouse IgG response. Previous investigations demonstrated that a large proportion of the anti‐mouse response was specific for idiotypic determinants of the mAb. This study demonstrates the feasibility of idiotype switching of therapeutic mAb to evade this anti‐idiotype response. In this way prolongation of the therapeutic effectiveness of mAb treatment can be achieved. Using different CD4‐specific mAb consecutively in rhesus monkeys it was possible to obtain therapeutic effectiveness in spite of host anti‐mouse IgG antibodies, provided that no anti‐idiotypic antibodies were present. Anti‐constant part antibodies may even enhance therapeutic effectiveness.
Relationship of B cell Fc receptors to T cell recognition of Mls antigen
Authors: Nicolas Jean‐Francois , Wegmann Dale , Lebrun Philippe , Kaiserlian Dominique , Tovey Julie , Glasebrook Andy L. 
Published: March 2007

AbstractThe Mls locus on chromosome 1 controls the expression of cellular determinants that are responsible for stimulating mixed lymphocyte reactions between H‐2‐identical strains. However, the biochemical nature of Mls antigenic determinants remains undefined. It has been proposed that Ly‐17 lymphoid cell surface antigens (also known as Ly.m.20.2 and LyM‐1) and Mls antigens could be identical because they are both encoded by loci on chromosome 1 and display similar tissue distribution. The Ly‐17 locus encodes polymorphic alleles of the IgG Fc receptor (FcγR). In the present study, two approaches were used to address the question of whether FcγR are involved in T cell recognition of Mls antigen. In the first approach we tested the effect of FcγR blockade by heat‐aggregated mouse IgG or anti‐FcγR monoclonal antibodies (2.4.G2) on the ability of an Ia+, FcγR+ Mlsa‐expressing B cell hybrid (LBB.3.4.16) to stimulate interleukin 2 secretion by an anti‐Mlsa‐specific T cell hybrid. We show that blockade of FcγR does not inhibit the Mlsa‐specific stimulation of T cells during a 24‐h culture period in which FcγR remain blocked. In the second approach, we derived irradiation‐induced variants of LBB.3.4.16 to dissociate FcγR expression and Mls antigen expression. We describe 2 LBB variants which no longer stimulate Mlsa‐reactive T cells but do express FcγR. Compared to parental LBB cells, the capacity of variant LBB cells to present soluble antigen to Ia‐restricted T cells is unaffected. Collectively, these results indicate that FcγR expression and Mlsa antigen stimulation can be dissociated. We conclude that FcγR expression may be necessary, but not sufficient for T cell recognition of Mls antigen.
Identification of intrathymic T progenitor cells by expression of Thy‐1, IL 2 receptor and CD3
Authors: Nakano Naoko , Hardy Richard R. , Kishimoto Tadamitsu 
Published: March 2007

AbstractImmature (L3T4−/Lyt‐2− “double‐negative”) thymocytes were separated into several functionally distinct fractions based on their expression of IL 2 receptors, Thy‐1 and CD3. The majority (60–70%) of double‐negative thymocytes in young adult mice lack detectable IL 2 receptor expression, have high levels of Thy‐1 and rapidly “progress” to a L3T4+ or L3T4+/Lyt‐2+ stage when cultured for 20 h in simple medium. In contrast, the IL 2 receptor‐positive fraction retains the double‐negative phenotype for as long as it survives in culture and addition of IL 2 has little or no effect on such cells. IL 2 does generate strong proliferation from a fraction of cells expressing low levels of Thy‐1, but not detectable IL 2 receptors. Such culture generates an unusual population of double‐negative cells that expresses the pan‐B cell molecule B220 and which kill both the NK target cell line YAC‐1 and the NK‐resistant line EL4. This Thy‐1‐low fraction includes all of the double‐negative thymocytes capable of T cell reconstitution. Thy‐1‐low fraction could be further separated into two populations with regards to CD3 expression. CD3− but not CD3+ population could reconstitute mature T cells, indicating that Thy‐1‐low, IL 2R− and CD3− cells are the most enriched population of intrathymic T cell progenitors.
Inhibition by anti‐HLA class II monoclonal antibodies of monocyte‐dependent T cell proliferation induced by monoclonal antibody OKT3
Authors: Ruggiero Giuseppina , Manzo Ciro , Fontana Silvia , Scala Giuseppe , Pirozzi Giuseppe , Ferrone Soldano , Zappacosta Serafino 
Published: March 2007

AbstractThe inhibitory effect of monoclonal antibodies (mAb) to monomorphic (locusrestricted and locus‐shared) and polymorphic determinants of HLA class II antigens on the monocyte‐dependent proliferation of T cells stimulated with mAb OKT3 has been studied. The effect appears to be specific, dose dependent, is not mediated by the Fc portion of mAb and reflects their interaction with the corresponding determinants. The anti‐HLA class II mAb do not have to be present in the culture throughout the incubation period, but are essential in early phases of mAb OKT3 T cell activation. Both monocytes and T cells are the targets of the inhibition exerted by the anti‐HLA class II mAb. Their inhibitory effect involves several steps in the sequence of events which leads to T cell proliferation, including interleukin (IL) 1 and 2 secretion, and IL 2 receptor expression.
T cell receptor γ chain variable gene rearrangements in acute lymphoblastic leukemias of T and B lineage
Authors: Boehm Thomas L. J. , Werle Andreas , Ganser Arnold , Kornhuber Bernhard , Drahovsky Dusan 
Published: March 2007

AbstractThe status of immunoglobulin and T cell receptor genes in acute lymphoblastic leukemia (ALL) of T and B lineage has been studied. Our data indicate that illegitimate gene rearrangements at immunoglobulin heavy chain (in T cell ALL), and T cell receptor β chain (in pre‐B ALL) genes are only rarely found (2 out of 30 patients). In contrast, T cell receptor γ chain gene rearrangements, characteristically found in T‐ALL, are also present in 7 of 18 patients with pre‐B ALL. Several features distinguish these illegitimate T cell receptor γ chain gene rearrangements from those in normal and leukemic T cells. Vγ genes located far upstream of the Jγ/Cγ complexes (Vγ2, Vγ3, Vγ4, Vγ5) appear to be preferentially used in normal adult peripheral blood T cells. In contrast, Vγ genes located immediately 5′ to the Jγ/Cγ complexes (Vγ8, Vγ9, Vγ10, Vγ11) predominate in Vγ‐Jγ recombinations observed in T‐ALL and pre‐B ALL. Whereas the Jγ2 region is primarily used in T cell receptor γ gene rearrangements observed in T‐ALL, those in pre‐B ALL are confined mostly to the Jγ1 region. These data suggest a limited accessibility of the T cell receptor γ chain gene locus for recombination processes in early stages of B cell differentiation.
A novel serine proteinase (HuTSP) isolated from a cloned human CD8+ cytolytic T cell line is expressed and secreted by activated CD4+ and CD8+ lymphocytes
Authors: Fruth Uli , Sinigaglia Francesco , Schlesier Michael , Kilgus Jochen , Kramer Michael D. , Simon Markus M. 
Published: March 2007

AbstractA novel proteinase, termed human T cell‐associated serine proteinase (HuTSP), has been highly purified from a human CD8+ T lymphocyte clone. By using a panel of chromogenic model peptide substrates the enzyme was found to specifically recognize L‐arginine and to cleave Tos‐Gly‐Pro‐Arg‐nitroanilide with high efficiency at a pH optimum of 10.5–11. Exposure to class‐specific proteinase inhibitors revealed that HuTSP is a serine endopeptidase. The enzyme has a mol. mass of ∼ 50 kDa (non‐reduced) and of ∼ 25–30 kDa (reduced) when analyzed by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis suggesting HuTSP to be a disulfide‐linked dimer. The enzyme is shown to be inducible by lectin in both CD4+ and CD8+ lymphocytes. Moreover, HuTSP was detected in a number of independent CD4+ and CD8+ T cell clones and was found to be released from effector cells upon ligand binding to the CD3‐T cell receptor complex.
Rearrangement and organization of T cell receptor gamma chain genes in human leukemic T cell lines
Authors: Kimura Nobuhiro , Du Ran‐Pan , Mak Tak W. 
Published: March 2007

AbstractSeventeen T cell leukemic lines, which are arrested at different stages of differentiation, were analyzed for γ‐chain rearrangement and expression using the constant region gene and representatives of the different families of Vγ chain genes. With the exception of the T cell line P30/OKUBO, which is arrested at the earliest stage (stage I), all the leukemic lines have rearranged their γ‐chain genes and transcripts can be detected in all but MOLT‐4 and P30/OKUBO cell lines. Although Vγ1 genes were rearranged and expressed in leukemic lines arrested at stages II, III and IV, Vγ2 and Vγ3 were only rearranged and expressed in cells at stage III (0/5 in stage II, 5/9 in stage III and 0/1 in stage 4). Thus, there may be a sequential usage of Vγ gene during human T cell ontogeny (although it is possible that this may just be a coincidence), similar to that which has been shown during murine ontogeny. Based on the rearrangement data, the genomic order of 5′ Vγ1‐Vγ2‐Vγ3‐J‐C 3′ is proposed.
A genetically determined lack of oral tolerance to ovalbumin is due to failure of the immune system to respond to intestinally derived tolerogen
Authors: Mowat Allan McI. , Lamont Alan G. , Bruce Maureen G. 
Published: March 2007

AbstractIn this study we have examined whether differences between mouse strains in the induction of tolerance after feeding ovalbumin (OVA) are due to differences in intestinal processing of OVA or are determined by the systemic immune system. Compared with major histocompatibility complex (MHC)‐congenic BALB/c mice, BALB/B mice develop much less tolerance of systemic delayed‐type hypersensitivity (DTH) and humoral immunity after feeding OVA and this defect is also expressed partially in (BALB/B × BALB/c)F1 animals. Serum taken from either BALB/c or BALB/B mice fed OVA 1 h before produced significant suppression of systemic DTH responses in BALB/c, but not in BALB/B mice. Although OVA‐fed BALB/B serum was slightly less tolerogenic than BALB/c serum, we conclude that the defective induction of oral tolerance in BALB/B mice is due primarily to a MHC‐influenced defect with the immune system. These findings support the idea that clinical food‐sensitive enteropathy reflects an immune response gene‐controlled defect in tolerance to dietary proteins.
Two types of gamma T cell receptors expressed by T cell acute lymphoblastic leukemias
Authors: van Dongen Jacques J. M. , Wolvers‐Tettero Ingrid L. M. , Seidman J. G. , Ang Siew‐Lan , van de Griend René J. , De Vries Evert F. R. , Borst Jannie 
Published: March 2007

AbstractCD3+ cells, isolated from peripheral blood of two patients with T cell acute lymphoblastic leukemia (T‐ALL), did not react with the monoclonal antibody WT31, which is thought to recognize a framework determinant on the conventional T cell receptor (TcR), consisting of disulfide‐linked α and β chains. The T‐ALL cells of neither patient synthesized TcRα mRNA; the cells of patient DD contained only truncated (D‐J) TcRβ mRNA, while the cells of patient HZ contained truncated as well as mature (V‐D‐J) TcRβ mRNA. The leukemic cells of both patients made TcRγ mRNA. At the cell surface, the T‐ALL cells of patient DD expressed a CD3‐associated disulfide‐linked dimer, which contained the TcRγ protein. On the leukemic cells of patient HZ the TcRγ protein was present as a 41‐44‐kDa CD3‐associated subunit in a noncovalently linked form. The TcRγ genes in the T‐ALL cells of patient DD were rearranged exclusively to the Cγ1 locus, while in the T‐ALL cells of patient HZ both Cγ1 alleles were deleted and rearrangement to the Cγ2 locus had occurred. The Cγ1 gene segment, just like the TcRα and TcRβ gene segments, contains a cysteine codon in its second exon. This cysteine residue is involved in the formation of the interchain disulfide bond. The human Cγ2 gene segment, however, does not contain a cysteine codon in its second exon. The absence of the cysteine residue in Cγ2 encoded TcRγ chains explains the lack of an interchain disulfide bond in the TcR on the T‐ALL cells of patient HZ. The TcR gene configuration, as well as the expression of TcR mRNA and TcR protein as observed in these two leukemias, is consistent with a model for T cell differentiation in which the TcRγ gene rearranges first to the Cγ1 locus prior to or coinciding with D‐J joining of the TcRβ gene, followed by rearrangement to the Cγ2 locus and V‐D‐J joining of the TcRβ gene.