bluuebunny/crossref_metadata_2025_split huggingface dataset:
Induction of lymphocyte locomotor capacity by a substratum‐dependent factor from mononuclear cells
Authors: Sundqvist Karl‐GÖSta , Otteskog Per 
Published: March 2007

AbstractMedia conditioned by human mononuclear cells contain a factor which renders freshly purified T lymphocytes motile and which is distinct from interleukin 1 and interleukin 2. The motility induced by this factor is morphologically indistinguishable from spontaneous lymphocyte motility. The factor is most effective when allowed to attach to the substratum. The effect of the factor on lymphocyte motility is detectable within 30 min but increases over a period of several hours. The relatively rapid action taken together with the ability to interact with both lymphocytes and the substratum point to the possibility that the factor rendering lymphocytes motile is a ligand which mediates cell‐substrate adhesion. Attempts to characterize this putative ligand using gel filtration chromatography yielded activity peaks at 500 to 600 kDa.
Human recombinant interleukin 4 induces normal B cells to produce soluble CD23/IgE‐binding factor analogous to that spontaneously released by lymphoblastoid B cell lines
Authors: Bonnefoy Jean Yves , Defrance Thierry , Peronne Catherine , Menetrier Christine , Rousset Françoise , Pène Jerome , Vries Jan E. De , Banchereau Jacques 
Published: March 2007

AbstractSurface‐labeled Epstein‐Barr virus (EBV)‐transformed lymphoblastoid RPMI 8866 cells release in their supernatant a radiolabeled 25‐kDa polypeptide which reacts with the Fee RL/CD23‐specific monoclonal antibody (mAb) 25 and which binds to IgE but not IgG (IgEBF/sCD23). IgE BF/sCD23 had an isoelectric point of 4.5–5.0. The reactivity of mAb 25 with IgE BF/sCD23 allowed us to set up a radioimmunoassay for detection of IgE BF/sCD23 in cell culture supernatants. Supernatants from Fee RL/ CD23+ cell lines were found to contain IgEBF/sCD23. Addition of human recombinant interleukin 4 (IL4) to normal human B cells cultures induced the production of IgEBF/sCD23. Activation of B cells with anti‐IgM antibody coupled to beads enhanced the IL4‐induced production of IgEBF/sCD23 when compared to nonactivated B cells. This correlates with the finding that anti‐IgM antibody‐activated B cells cultured with IL4 express more FceRL/CD23 than B cells cultured with IL4 alone. The biochemical characteristics of radiolabeled IgE BF/sCD23 immunoprecipitated by mAb 25 from the supernatants of normal B cells cultured with IL 4 were identical to those of the IgEBF/sCD23 isolated from EBV‐transformed cell line supernatants. Addition of interferon‐γ to B cells cultured with IL 4 strongly decreased the level of IgE BF/sCD23 in culture supernatants correlating with the observed decrease of FceRL/CD23 on B cell surface. These data demonstrate that normal human B cells cultured in the presence of IL 4 produce an IgE‐binding factor (sCD23) biochemically and antigenically equivalent to that spontaneously produced by EBV‐transformed lymphoblastoid cell lines.
Anti‐CD3 antibodies induce T helper function for human B cell differentiation in vitro by an interleukin 2‐independent pathway
Authors: Sauerwein Robert W. , Van Meer Walter G. J. Der , Oostveen Johan W. Van , Miedema Frank , Aarden Lucien A. 
Published: March 2007

AbstractPreviously we have shown that interleukin 2 (IL 2) is an essential mediator in T cell‐dependent B cell differentiation induced by pokeweed mitogen. Here we show that activation with monoclonal anti‐CD3 antibodies of peripheral blood T cells led to the induction of helper activity for IgM secretion by human B cells from a prolymphatic leukemia. With the use of monoclonal antibodies against the IL2 receptor and CD3+ CD4+ CD8− chronic lymphatic leukemia T cells with a strongly reduced capacity to produce IL2, it was demonstrated that the anti‐CD3‐driven Ig secretion was obtained by an IL 2‐independent pathway. The T cell help in this system is mediated by soluble factors.
The induction of organ‐specific antibodies during the graft‐vs. ‐host reaction
Authors: Kupers Rudolf C. , Suiter Tobias , Gleichmann Ernst , Rose Noel R. 
Published: March 2007

AbstractDuring the parent (P) into F1 hybrid graft‐vs.‐host reaction (GVHR), nuclear, leukocyte and erythrocyte autoantibodies are commonly seen. The specificity of these autoantibodies is reminiscent of those found in systemic lupus erythematosus (SLE) patients and SLE‐prone mice. Organ‐specific antibodies, however, including thyroglobulin (Tg) antibodies do not arise spontaneously. There have been conflicting reports about the ability of exogenous Tg to induce an anti‐Tg response during the GVHR. We have re‐examined this question in greater detail.Using the murine P → F1 GVHR system, the results of this work demonstrate that mouse thyroglobulin (MTg)‐specific antibodies can be induced during a GVHR. However, mice must both be undergoing a GVHR, and have received exogenous MTg. The highest autoantibody response occurs if mice are injected with mouse thyroid extract or purified MTg at the time of P → F1 cell transfer. The anti‐MTg response is MTg dose dependent. The ability to induce anti‐MTg antibody was not major histocompatibility complex restricted, for both the DBA/2→B6D2F1 (low responder H‐2 haplotypes to MTg), and AKR or DBA/2→ AKD2FI (high/low responder → high responder haplotype) GVHR gave similar responses. The anti‐MTg titers peaked between days 7–10 and declined thereafter. In contrast, antibodies to dsDNA were not present at this early time, but developed after several weeks. We conclude that organ‐specific autoantibodies can be induced during a GVHR if the appropriate antigen(s) are presented near the time of GVHR induction.
Signals involved in T cell activation. T cell proliferation induced through the synergistic action of anti‐CD28 and anti‐CD2 monoclonal antibodies
Authors: Lier René A. W. Van , Brouwer Miranda , Aarden Lueien A. 
Published: March 2007

AbstractMonoclonal antibodies (mAb) directed against the T cell differentiation antigen CD28 (Tp44) induce proliferation of resting T lymphocytes in the presence of phorbol esters. Moreover, it has been reported that such antibodies augment and sustain T cell proliferation induced by soluble antigens, phytohemagglutinin and anti‐CD3 mAb. Recently, we have shown that in monocyte‐depleted T cell suspensions, anti‐CD28 mAb 9.3 and Kolt‐2 were able to circumvent the requirement for interleukin 2 (IL2) in T cell proliferation induced by soluble anti‐CD3 antibodies. Apart from the synergy of anti‐CD28 antibodies with phorbol myristate acetate and anti‐CD3 antibodies, we found that anti‐CD28 mAb were able to induce T cell mitogenesis in combination with an E rosette‐blocking anti‐CD2 antibody. In this report, we show that antibodies directed against different epitopes on the CD2 antigen can synergize with anti‐CD28 mAb. Furthermore, we demonstrate that proliferation induced through the synergistic action of anti‐CD28 mAb with anti‐CD2 antibodies can be induced in the absence of accessory cells and is accompanied by the production of IL 2 and the excpression of IL2 receptors. We were unable to induce detectable Ca2+ mobilization through the simultaneous binding of anti‐CD28 and anti‐CD2 mAb. Taken together, these data show that IL2‐dependent proliferation can be induced through the simultaneous binding of anti‐CD28 and anti‐CD2 antibodies, possibly through phosphatidyl inositol‐independent pathways. The observations may provide further insight into the activation mechanisms of human T cells.
Nonrandom TRGγ variable gene rearrangement in normal human T cells and T cell leukemias
Authors: Migone Nicola , Casorati Giulla , Celle Paola Francia Di , Lusso Paolo , Foa Robin , Lefranc Marie‐Paule 
Published: March 2007

AbstractTo estimate the extent of the TRGγ variable (V) gene repertoire used in human T cell ontogeny, we have analyzed the variety of Vγ, gene rearrangements in a large series of T and non‐T acute and chronic leukemias. A limited heterogeneity of rearranged fragments was observed: only 13 types of differently rearranged fragments, four of which occurred only once, were found among 80 rearranged chromosomes. Furthermore, in the leukemic population as a whole, the frequency distribution of the most common types of rearranged Vγ, gene‐containing fragments appeared to be nonrandom (p < 0.01). Of interest is the clear preference for functional vs. nonfunctional V, genes (nonfunctional genes being those which carry frameshifts or nonsense mutations but which presumably can still rearrange due to their conserved signal sequences). We discuss the possibilities that this preference may result either from selection of the TRGγ product at some stage during T cell development or, alternatively, from an intrinsic, antigen‐independent polarity in Vγ, gene activation.
Down‐regulation of the T cell receptor by a mitogenic anti‐Thy‐1 antibody
Authors: Tomonari Kyuhei 
Published: March 2007

AbstractAntigen‐specific unresponsiveness lasting at least 2 weeks can be induced in a T cell clone by 24‐h pretreatment with mitogenic anti‐T cell receptor antibodies. In this report the relationship is explored between the antigen‐specific unresponsiveness and activation pathways triggered via the T cell receptor and Thy‐1: the latter pathway is dependent on the former. A mitogenic anti‐Thy‐1 antibody (KT16) made the T cell clone unresponsive to specific antigen and to an anti‐T cell receptor antibody coupled to Sepharose. The unresponsiveness lasted for at least 7 days. However, cells made unresponsive to specific antigen in these ways (the T cell receptor and Thy‐1) could be activated by both interleukin 2 and KT16. KT16 down‐modulated the T cell receptor immediately after the pretreatment, but not on day 7 after the pretreatment. These facts indicate that the state of the unresponsiveness was caused by blocking transduc‐tion of an activation signal triggered by the T cell receptor to an activation pathway shared by the T cell receptor and Thy‐1.
The T11 (CD2) cDNA encodes a transmembrane protein which expresses T111, T112 and T113 epitopes but which does not independently mediate calcium influx: analysis by gene transfer in a baculovirus system
Authors: Alcover Andres , Chang Hsiu‐Ching , Sayre Peter H. , Hussey Rebecca E. , Reinherz Ellis L. 
Published: March 2007

AbstractTo determine whether a full‐length human T11 (CD2) cDNA encodes a protein which expresses all three T11 epitopes (T 111, T112, T113) and independently triggers activation in a cell other than a T lymphocyte, a baculovirus expression system was employed. Here we show that a recombinant T11 cDNA‐containing baculovirus can induce high‐level expression of T111, T112 and T113 epitopes on the surface of gut epithelial SF9 cells. However, in this environment the T11 protein cannot be triggered to transduce a signal resulting in an elevation of the cytosolic free Ca2+ as is known to occur in T lymphocytes. These results support the notion that T11 functions in a coordinate fashion with other intracellular lymphoid components.
Recombinant human granulocyte‐macrophage colony‐stimulating factor induces secretion of autoinhibitory monokines by U‐937 cells
Authors: Lindemann Albrecht , Riedel Detlev , Oster Wolfang , Mertelsmann Roland , Herrmann Friedhelm 
Published: March 2007

AbstractColony‐stimulating factors are required for survival proliferation, differentiation and functional activation of granulocytes, macrophages and their precursor cells. In the present report, however, we demonstrate antiproliferative activity of recombinant human (rh) granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) on mono‐blast cell line U‐937 and provide evidence for the involvement of tumor necrosis factor alpha TNF‐α and interleukin 1 beta (IL 1β) in its growth inhibitory action. GM‐CSF (but not granulocyte CSF, G‐CSF or macrophage CSF, M‐CSF) suppressed DNA synthesis and self renewal of U‐937 cells. Similarly, medium conditioned by U‐937 cells in response to GM‐CSF (GM‐CSF U‐937‐CM) was able to reduce clonogenicity and [3H] thymidine uptake by U‐937 cells. Since neutralization of GM‐CSF present in GM‐CSF U‐937‐CM by monoclonal antibody to GM‐CSF did not abrogate the autoinhibitory activity present in GM‐CSF U‐937‐CM, we considered the possibility that other soluble molecules are released by U‐937 cells upon GM‐CSF stimulation. Neutralization by antibodies to IL1β and TNF‐α suggested that both monokines could be the antiproliferative principle operating in GM‐CSF U‐937‐CM. Moreover, employing IL 1β‐specific enzyme‐linked immunosorbent assay, TNF‐α specific radioimmunoassay, Northern analysis using a cloned TNF‐α‐specific cDNA and an oligonucleotide probe for IL 1β, we demonstrate GM‐CSF‐inducible IL 1β and TNF‐α gene expression by U‐937 cells at the mRNA and protein level. Although M‐CSF expression was induced under similar conditions, M‐CSF failed to inhibit growth of U‐937 cells.
The molecular interactions with helper T cells which limit antigen‐specific B cell differentiation
Authors: Julius Michael H. , Rammensee Hans‐Georg , Ratcliffe Michael J. H. , Lamers Marinus C. , Langhorne Jean , Köhler Georges 
Published: March 2007

AbstractHelper T (Th) cell‐dependent activation requirements for 2,4,6‐trinitrophenyl (TNP)‐specific resting B cells obtained from mice transgenic for Sp‐6 μ,χ genes were analyzed. Carrier‐specific T cell help required linked recognition of TNP carrier and was functionally restricted by the B cell major histocompatibility complex. However, histoincompatible T cell‐B cell conjugates formed by bridging surface immunoglobulin and Th cell receptor for antigen (TcR) through TNP‐conjugated anti‐TcR antibodies resulted in the efficient differentiation of TNP‐specific B cells. Thus, Th cell‐dependent cognate recognition of B cells is not obligatory. Specific conjugate formation could be obviated by using unconjugated fragments of anti‐TcR antibodies. If dimeric, these fragments supported the Th cell‐dependent differentiation of co‐cultured histoincompatible resting B cells. Unconjugated monomeric fragments were ineffective, demonstrating the necessity for TcR cross‐linking. Resting B cells from Sp‐6' mice rendered TNP‐conjugated monomeric fragments of anti‐TcR antibodies effectively multivalent, thereby satisfying conditions for the activation of co‐cultured Th cells. The results demonstrate that Th cells do not transduce activation signals through TcR recognition of B cell membrane‐associated ligand which limit the induction of B cell differentiation. Cross‐linking of TcR on Th cells is required, sufficient and can be induced through interaction with the antigen‐specific B cell surface.
A noncognate interaction with anti‐receptor antibody‐activated helper T cells induces small resting murine B cells to proliferate and to secrete antibody
Authors: Owens Trevor 
Published: March 2007

AbstractCulture of small resting allogeneic B cells (of an irrelevant haplotype) with two clones of T helper (Th) cells that were activated by the F23.1 anti‐T cell receptor antibody led to the activation of B cells to proliferate and to secrete antibody. Th cell supernatants by themselves had no effect on resting B cells (even in the presence of intact F23.1 antibody), but could induce antibody secretion by anti‐Ig‐preactivated B cells. Both F23.1‐1 clones (E9.D4 and 4.35F2) and one F23.1‐ clone (D2.2) could synergize with supernatants from activated E9.D4 T cells to induce B cell activation. F(ab'), fragments of F23.1 induced E9.D4 to activate B cells as efficiently as intact F23.1, and B cell populations that had been incubated with F23.1 were not activated when cultured with E9.D4, although T cells recognized cell‐presented F23.1 and were weakly activated. Reduction of the density of F23.1 adsorbed to plastic resulted in weak T cell activation, and these T cells did not induce B cell responses. Haptenated B cell populations, although recognized by E9.D4, were not activated. Separation of T and B cells by a 0.4‐μm membrane prevented T‐dependent B cell activation, although Th cell‐derived B cell‐activating lymphokines would be assayed across these membranes. These results suggest a polyclonal noncognate B cell activation that depends on physical contact between B cells and activated T cells. The requirement for a cognate interaction of Th with B cells for the production and delivery of B help can therefore be overcome by activating Th cells with high densities of T cell receptor ligands.
Induction of the receptor for the Fc portion of IgA by secretory IgA on human T cell lines and T cell clones
Authors: Brière Francine , Paliard Xavier , Vries Jan E. De 
Published: March 2007

AbstractHuman colostral secretory IgA (SIgA; predominantly present in dimeric of polymeric forms) induces receptors for the Fc portion of IgA (FcαR) on cloned and noncloned human T cell lines. The binding of SIgA to its FcR was isotype specific, since it was not inhibited by IgG or IgM. Binding of SIgA was also not affected by ovalbumin or asialoglycoprotein. In addition, SIgA blocked the binding of directly fluorescein isothiocyanate‐labeled SIgA in a dose‐dependent fashion, whereas IgG and IgM were ineffective, confirming the specificity of the binding.Expression of FcαR was specifically induced by SIgA, whereas serum IgA (predominantly present in monomeric form) had no effect. In addition, IgG, IgM and IgE were ineffective. This induction of FcαR by SIgA was dose dependent. Optimal induction was observed at concentrations of 500 μg/ml after incubation times of 48 h. FcαR were predominantly induced on T cell lines and T cell clones derived from tonsils. T cell lines and T cell clones established from peripheral blood could only occasionally be induced to express FcαR. Induction of FcαR expression was obtained both with CD4+ and CD8+ T cell clones. FcαR were readily induced on T cell clones tested up to 6 days after activation by alloantigen. T cell clones tested 10‐12 days after alloantigen activation failed to respond to SIgA. These results indicate that the inducibility of FcαR is related to the activation stage of the T cell clones.
In human monocytes a strong correlation exists between expression of the m3 antigen, fc‐mediated phagocytic activity and failure to participate in extracellular antibody‐dependent cytotoxicity
Authors: Gidlund Magnus , Rossi Paolo , Cotran Paul , Ramstedt Urban , Wigzell Hans 
Published: March 2007

AbstractHuman fresh blood monocytes can phagocytize and lyse antibody‐coated target cells by contact with membrane Fc receptors. Recently, the monocyte differentiation antigen Leu M3 has been described to be associated with monocytelmacrophage maturation pathway and to be linked to functionally distinct monocyte subsets. In the present study peripheral blood monocytes were separated into M3‐ and M3‐ subsets, and evaluated for their ability to mediate antibody‐driven effector functions. A clear cut functional difference could be demonstrated. M3' monocytes phagocytize antibody‐coated sheep red cells but do not carry out contact‐mediated extracellular lysis. In contrast, M3‐ monocytes have exactly the opposite functional features and they mediate cytolysis without exhibiting any phagocytic activity.By using phenotypically defined clones of the U937 histiocytic cell line, the segregation of different lytic abilities and their linkage of the M3 phenotype have been confirmed.
Biochemical characterization and biological effects of partially purified b cell‐activating factor (bcaf)
Authors: Roth Claude , Moreau Jean‐Louis , Korner Marie , Jankovic Dragana , Thèze Jacques 
Published: March 2007

AbstractB cell‐activating factor (BCAF) has been characterized and partially purified from the supernatant of the murine tumor T cell line 373. BCAF has an apparent molecular mass of 15 to 20 kDa when analyzed by Superose 12 fast protein liquid chromatography (FPLC) gel filtration and a PI of 4.5 to 5.0 when analyzed by FPLC chromatofocusing. Concentrated supernatant was applied to a nickel chelating column and unadsorbed active material was further purified by two sequential C4 reversephase high‐performance liquid chromatography steps. This purification procedure allowed a complete separation of interleukin 2 and interleukin 4 activities from BCAF. This partially purified BCAF induces Ia expression, cell size increase and proliferation of small resting B cells. Furthermore, we have shown that the activity of partially purified BCAF is insensitive to treatment by monoclonal antibodies specific for interleukin 4 and interleukin 5.
The glioblastoma‐derived t cell suppressor factor/ transforming growth factor‐β2 inhibits t cell growth without affecting the interaction of interleukin 2 with its receptor
Authors: Siepl Christine , Bodmer Stefan , Frel Karl , MacDonald H. Robson , Martin Rainer De , Hofer Erhard , Fontana Adriano 
Published: March 2007

AbstractHuman glioblastoma cells secrete a peptide termed glioblastoma‐derived T cell suppressor factor (G‐TsF) which inhibits T cell activation. Recently, purification and cloning of G‐TsF revealed that G‐TsF is identical to transforming growth factor‐β2. As shown here, G‐TsF suppresses the growth of an ovalbumin‐specific mouse T helper cell clone (OVA‐7 T) independently of the stimulus used being either (a) antigen in the presence of antigen‐presenting cells, or (b) interleukin 2 (IL2) or (c) phorbol ester and calcium ionophore. Furthermore, in the presence of antibodies against IL2 receptors, G‐TsF was able to suppress the residual proliferation still observed when OVA‐7 T were stimulated with phorbol esterhonophore. G‐TsF failed to inhibit the release of IL3 from OVA‐7 T activated with IL2. Taken together, the data provide evidence that G‐TsF does not directly interfere with interactions of IL2 with its receptor but rather inhibits T cell activation by interfering with an as yet unidentified pathway used by both IL2 and phorbol esterhonophore. When analyzing different monokines and lymphokines for its effect on G‐TsF‐induced suppression of T cell growth the only factor found to partially neutralize the effect of G‐TsF was tumor necrosis factor‐α.
Heterohybridomas secreting human monoclonal antibodies against haemophilus influenzae type b
Authors: Martin Denis , Larose Yolande , Hamel JoséE , Lagacé Jacqueline , Brodeur Bernard R. 
Published: March 2007

AbstractSeven human monoclonal antibodies (HmAb) directed against outer membrane antigens of Haemophilus influenzae type b (Hib) were produced by fusing Sp2/HPT heteromyeloma cells with human tonsillar lymphocytes sensitized in vitro for 6 days. The heterohybridomas were maintained in culture for at least one year and secreted, when cultured in Dulbecco's modified Eagle's medium without fetal calf serum, between 1 and 15 μg/106 cells/m1/24 h. All of the HmAb were IgGs except HiH‐12 which is an IgM. Antibodies directed against the lipopolysaccharide and proteins of apparent molecular masses of 43, 37 and 27 kDa were identified by immunoblotting of sodium dodecyl sulfate‐polyacrylamide gel electrophoresis patterns of outer membrane. Binding radioimmunoassay with live bacteria showed that five out of seven HmAb adsorbed to cell surface‐exposed antigenic determinants. HmAb HiH‐6, HiH‐7 and HiH‐10 reacted with a surface‐accessible determinant on the 43‐kDa outer membrane protein. In a dot enzyme immunoassay, these HmAb recognized 103 out of 111 Hib strains isolated worldwide. The strains were selected to represent the most common genotypic variations among Hib. None of these HmAb reacted with other bacterial species tested. These HmAb may serve to study the bacterial surface antigens implicated in the human humoral response and protection to Hib infections.