bluuebunny/crossref_metadata_2025_split huggingface dataset:
The α3 domain of major histocompatibility complex class I molecules plays a critical role in cytotoxic T lymphocyte stimulation
Authors: Samberg Nancy L. , Scarlett Elizabeth C. , Stauss Hans J. 
Published: March 2007

AbstractAllogeneic major histocompatibility complex class I molecules induce strong cytotoxic T lymphocyte (CTL) responses whereas xenogeneic molecules do not. We have tested a series of mouse/human hybrid molecules for their ability to stimulate mouse CTL. The molecules with murine α3 domains consistently stimulated stronger CTL responses than those with human α3 domains, independent of the species origin of the N‐terminal α1 or α2 domains. We have found that the ability of class I molecules to induce strong cytotoxic responses correlates positively with their ability to stimulate expansion of the CD8+CD4− T cell subset. The results indicate that mouse T cells can recognize class I molecules with human α1 and/or α2 domains, but for efficient stimulation of these T cells it is important that the immunizing molecule contains a murine α3 domain. We suggest that T cell priming requires an efficient interaction of CD8 with the class I α3 domain, and this shows some species restriction.
An antigenic peptide of the HIV‐1 NEF protein recognized by cytotoxic T lymphocytes of seropositive individuals in association with different HLA‐B
Authors: Culmann BÉAtrice , Gomard Elisabeth , Kiény Marie‐Paule , Guy Bruno , Dreyfus FrançOis , Saimot Adrien‐GÉRard , Sereni Daniel , Lévy Jean‐Paul 
Published: March 2007

AbstractBy using target cells that expressed only the regulatory NEF protein of the human immunodeficiency virus (HIV), we were able to identify specific cytolytic T cells (CTL) from most of the seropositive patients tested. This NEF‐specific cytolytic activity was mediated by CD8+ lymphocytes. In two different donors, we identified a unique peptide in the NEF protein that could be recognized in association with two different HLA class I molecules. The definition of such a peptide should prove useful in evaluating vaccine strategies.
Murine macrophage precursor characterization. I. Production, phenotype and differentiation of macrophage precursor hybrids
Authors: Leenen Pieter J. M. , Slieker Walentina A. T. , Melis Marleen , van Ewijk Willem 
Published: March 2007

AbstractThis study reports on the earliest stages of mononuclear phagocyte differentiation. A crucial question in this developmental process is whether mature macrophage (Mϕ) heterogeneity is already appointed at the precursor cell level. For this purpose, we produced clonal populations of mononuclear phagocytes from bone marrow culture by somatic cell hybridization with two hypoxanthine, aminopterin, thymidine‐sensitive myeloid cell lines. A panel of 22 stable hybrids was obtained from these fusions. Differentiation stage analysis of the hybrids indicated that all cell lines had immature mononuclear phagocyte characteristics. The hybrids exhibited typical myeloid morphology and mainly nonadherent growth. Mature Mϕ features, such as expression of the cell surface antigens Mac‐1, Mac‐2 and F4/80, phagocytosis of latex beads, and expression of nonspecific esterase and acid phosphatase activity, were virtually absent. The immature Mϕ markers Thy‐1, MIV 25 and MIV 52, on the other hand, were readily expressed, although heterogeneity was observed among different hybrid cell lines.We then analyzed the differentiation potential of seven hybrids by culture of the cells in the presence of post‐lipopolysaccharide serum supplemented with interferon‐γ and found that the expression of mature Mϕ characteristics was induced. However, the various hybrids showed divergent patterns of mature Mϕ marker induction. ROC2 cells, for instance, showed extensive morphological and phenotypical differentiation without concomitant induction of phagocytosis. In contrast, W1C4 cells showed significant induction of phagocytosis without simultaneous increase of phosphatase and esterase activity. R1C1 cells were unique in the strong induction of Ia antigen expression.Together, our data indicate that (a) early Mϕ differentiation stages can be rescued by somatic cell hybridization, and that (b) the obtained cell lines are able to mature according to divergent differentiation programs.
Murine macrophage precursor characterization. II. Monoclonal antibodies against macrophage precursor antigens
Authors: Leenen Pieter J. M. , Melis Marleen , Slieker Walentina A. T. , van Ewijk Willem 
Published: March 2007

AbstractThe aim of the present study was the phenotypical analysis of early stages in macrophage (Mϕ) differentiation. For this purpose, we produced a panel of syngeneic rat hybridomas, which secreted antibodies (mAb) against Mϕ precursor antigens. As immunogens we used immortalized Mϕ precursors (P. J. M. Leenen et al., Eur. J. Immunol. 1990. 20: 15). We screened the obtained mAb in the following in vitro models of Mϕ differentiation: (a) a panel of Mϕ cell lines ordered in a linear differentiated sequence; (b) immature and mature mononuclear phagocytes obtained from bone marrow (BM) culture; (c) a panel of Mϕ precursor hybrids, and (d) differentiated and control Mϕ precursor hybrid cells.Four mAb, ER‐MP12, ER‐MP20, ER‐MP54 and ER‐MP58, were selected. These mAb recognize antigens which disappear in the course of Mϕ differentiation. Next, we investigated whether these mAb also recognized Mϕ precursors in normal BM. For this purpose, ER‐MP‐positive and ‐negative BM fractions were isolated using a fluorescence‐activated cell sorter. Fractions were cultured in Mϕ‐colony‐stimulating factor‐containing conditioned medium, and the resulting mature Mϕ progeny was quantified using the MTT assay. The present experiments indicate that ER‐MP12 and ER‐MP20 detect a subpopulation of BM Mϕ precursors, whereas ER‐MP58 stains virtually all Mϕ precursors.Biochemical analysis of radioiodinated antigens revealed that these mAb recognize different molecules. ER‐MP12 and ER‐MP20 bound to single‐chain (glyco)proteins of 140 kDa and 14 kDa, respectively. ER‐MP54 precipitated multiple polypeptides, of which the major chains have an apparent molecular mass of 90, 80‐85 and 70‐75 kDa. Based on the molecular mass of the recognized antigens and the mAb specificities we conclude that ER‐MP12, ER‐MP54 and ER‐MP58 recognize hitherto unknown antigens of murine Mϕ precursor cells. The antigen detected by ER‐MP20 is most likely identical to Ly‐6C.
Selective elimination of double‐positive immature thymocytes by a thymic epithelial cell line
Authors: Nakashima Manabu , Mori Keiko , Maeda Kenichi , Kishi Hiroyuki , Hirata Kazuho , Kawabuchi Masaru , Watanabe Takeshi 
Published: March 2007

AbstractA cloned epithelial cell line, TEL‐2, has been established from the stroma tissues of normal mouse thymus. Incubation of mouse thymocytes on TEL‐2 cells resulted in the selective elimination of double‐positive (CD4+CD8+ cells from the culture, whereas single‐positive (CD4+ CD8− or CD4−CD8) thymocytes remaining in the culture were concentrated in non‐integrated cell population. The CD3− or CD3 low‐positive thymocytes were also eliminated by the TEL‐2 cells from the culture, followed by the concentration of CD3 high‐positive cells in the culture. Only intact viable thymocytes were integrated into TEL‐2 cells. Electron microscopic examination showed that the integrated cells into TEL‐2 cytoplasm were gradually degenerated. Mature single‐positive T cells, mature B cells or double‐negative thymocytes were not integrated into TEL‐2 cells. The TEL‐2 cell may provide information on the mechanism of selective disappearance of double‐positive immature cells from the thymus.
Activation of bone marrow‐derived mouse macrophages by bacterial lipopeptide: cytokine production, phagocytosis and Ia expression
Authors: Hauschildt Sunna , Hoffmann Petra , Beuscher H. Ulrich , Dufhues Gabriele , Heinrich Peter , Wiesmüller Karl‐Heinz , Jung Günther , Bessler Wolfgang G. 
Published: March 2007

AbstractThe lipopeptide N‐palmitoyl‐S‐(2,3‐bis(palmitoyloxy)‐(2RS)‐propyl)‐(R)‐cysteinyl‐alanyl‐glycine (Pam3Cys‐Ala‐Gly), a synthetic analogue of the N‐terminal part of bacterial lipoprotein, induces the secretion of interleukin (IL) 1, IL 6 and tumor necrosis factor (TNF)‐α in bone marrow‐derived macrophages that have been cultured in vitro for up to 20 days. IL 6 and TNF‐α secretion increased from day 6 to day 20 whereas IL 1 secretion increased until day 13 and decreased on day 20. In contrast to the enhancement of cytokine production, phagocytosis of IgG‐coated sheep erythrocytes and Ia expression were found to be diminished after treatment with lipopeptide for 24 h. Morphological studies revealed lipopeptide‐induced changes of macrophage cultures. The data presented here show the potential of the lipopeptide as a strong activator of bone marrow‐derived macrophages.
Specificity and cross‐reactive idiotypes of anti‐glomerular basement membrane autoantibodies in HgCl2‐induced autoimmune glomerulonephritis
Authors: Guéry Jean‐Charles , Druet Elvira , Glotz Denis , Hirsch François , Mandet Chantal , De Heer Emile , Druet Phillippe 
Published: March 2007

AbstractMurcury‐induced autoimmune glomerulonephritis in the Brown‐Norway (BN) rat is characterized by the successive appearance of linear and granular glomerular IgG deposits. Anti‐laminin autoantibodies represent the major part of the anti‐glomerular basement membrane (GBM) antibodies produced in this model. Fusions were performed in this model and four anti‐GBM monoclonal antibodies (mAb) were obtained. Three of them were laminin specific. Using rabbit anti‐idiotype antibodies, cross‐reactive idiotypes (CRId) were characterized on anti‐laminin antibodies. They were expressed on the three anti‐laminin mAb, on kidney‐eluted and circulating anti‐laminin antibodies. CRId‐bearing immunoglobulins were detected transiently in the circulation and paralleled the anti‐laminin antibody activity. By immunofluorescence studies on kidney cryostat sections two different CRId were defined. One was localized close to the antigen‐combining site since it was not revealed on kidney‐bound antibodies, in contrast with the second CRId. This latter CRId was also found deposited in a typical linear pattern in the early phase of the disease and in a granular pattern in the late phase, demonstrating that these CRId are components of immune deposits. Taken together, these results suggest that in this model of T‐dependent polyclonal B cell activation, restricted sets of V genes encode for at least a part of the anti‐GBM autoantibodies.
Rat anti‐glomerular basement membrane antibodies in toxin‐induced autoimmunity and in chronic graft‐vs.‐host reaction share recurrent idiotypes
Authors: Guéry Jean‐Charles , Tournade Hervé , Pelletier Lucette , Druet Elvira , Druet Philippe 
Published: March 2007

AbstractCross‐reactive idiotypes (CRId) borne on autoanti‐glomerular basement membrane antibodies of Brown‐Norway (BN) rats with mercury‐induced glomerulonephritis have been described in the preceding study (Guéry, J.‐C. et al., Eur. J. Immunol. 1990. 20: 93). BN rats treated with sodium aurothiopropanol sulfonate or D‐penicillamine, as well as (LEW×BN)F1 hybrids transferred with BN rat spleen cells, developed quite similar autoimmune abnormalities. In the present study, it is shown that immunoglobulins bearing such “public” idiotypes are also produced and deposited in the kidney in these three models. The CRId here described may, therefore, be considered as a marker of sets of recurrently expressed V region genes during the course of these autoimmune disorders. Anti‐self class II T cells are present in the three models of toxin‐induced autoimmunity and anti‐allo class II T cells are responsible for the chronic graft‐vs.‐host reaction. The same B cell clones are probably triggered during these processes as a consequence of a polyclonal B cell activation mediated by anti‐class II T cells.
Specific high‐affinity receptors for interferon‐γ on mouse bone marrow‐derived mast cells: inhibitory effect of interferon‐γ on mast cell precursors
Authors: Nafziger Joëlle , Arock Michel , Guillosson Jean‐Jacques , Wietzerbin Juana 
Published: March 2007

AbstractCultured mast cells derived from murine bone marrow were investigated for the presence of specific interferon‐γ (IFN‐γ) receptors, and for the effects of IFN‐γ on mast cell proliferation. 125I‐labeled recombinant IFN‐γ (125I‐Mu‐rIFN‐γ) was shown to bind to high‐affinity receptors on these cells. Scatchard analysis of binding data indicated the presence of about 500 homogeneous binding sites per cell, with an apparent equilibrium dissociation constant of 3×10−10 M. The binding of 125I‐Mu‐rIFN‐γ to mast cells was inhibited by unlabeled Mu‐rIFN‐γ but not by unlabeled Mu‐IFN‐α/β. Cross‐linking of 125I‐Mu‐rIFN‐γ to mast cell membrane proteins using a cross‐linking agent yielded a predominant complex of 100 ± 10 kDa on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and autoradiography which IFN‐γ‐receptor complex. To assess the biological significance of these receptors, we studied the effects of Mu‐rIFN‐γ on mast cell proliferation, which was markedly inhibited in mast cell precursors but not in mature mast cells. These in vitro results are in agreement with the antiproliferative effect of IFN‐γ previously reported for other hematopoietic progenitors, and suggest that IFN‐γ could find its application in the treatment of human systemic mastocytosis.
Characterization of rat tissue cultured mast cells
Authors: Chan Bosco M. C. , Ra Chisei , Hu Weining , McNeill Karol , Miller Hugh R. P. , Befus Dean , Kinet Jean Pierre , Froese Arnold 
Published: March 2007

AbstractTwelve continuous rat tissue cultured mast cell (MC) lines were established by prolonged culture of rat peritoneal MC in the absence of added factors or feeder layers. Two of these lines, RCMC1 and RCMC2, have been briefly described previously, seven others are now also described. Both RCMC1 and RCMC2 lack a marker chromosomes present on RBL‐CA10.7 cells. All lines were found to express the phenotype of mucosal MC as defined by alcian blue‐positive and safranin 0‐negative staining, the presence of rat MC protease II and a low histamine content. When analyzed for high‐(FcϵRI) and low‐affinity (FcϵRL) receptors for IgE, the various lines yielded a variety of receptor patterns. Northern blot analysis of the RNA of RCMC1, RCMC2 and RBL‐CA10.7 revealed that all three cell lines contained the same mRNA species for the α, β and γ subunits for FcϵRI previously found in another rat basophilic leukemia cell line. Quantitation of the relative amounts of α, β and γ mRNA did not correlate with the expression of the relative amounts of FcϵRI(α) in these cells. The relative amounts of mRNA for all these subunits of RCMC2 were equal or higher than those of RCMC1, suggesting that the low expression of FcϵRI(α) on the former was a consequence of post‐transcriptional events. Analysis of a RCMC1 clone over a 6‐month period revealed changes in the expression of both FcϵRI(α) and FcϵRL.
Complement regulation on the surface of cultured schistosomula and adult worms of Schistosoma mansoni
Authors: Marikovsky Moshe , Parizade Miriam , Arnon Ruth , Fishelson Zvi 
Published: March 2007

AbstractCercaria and freshly prepared schistosomula of Schistosoma mansoni are highly sensitive to complement. However, early in their maturation, the schistosomula become resistant to complement killing. This conversion is preceded by a rapid and massive release of several acetabular proteases and of the glycocalyx coat. Thus, shedding of the glycocalyx which is a major immunogen and a strong activator of the alternative pathway of complement permits the parasite to escape immune damage. Mechanically transformed schistosomula, which were cultured in a defined synthetic medium and developed complement resistance, could be converted by proteolysis to complement sensitivity. Trypsin and pronase markedly increased the susceptibility of cultured schistosomula to complement. The trypsin‐induced complement sensitivity persisted for at least 19 h without recovery of resistance. Similar treatment with trypsin produced complete killing of adult worms by complement in absence of antibodies. Efficient killing was obtained with normal human serum (NHS), with normal guinea pig serum (GpS), and with C4‐depleted HS and C4‐deficient GpS indicating that the killing was mediated by the cytolytic alternative pathway of complement. Larger quantities of C3b with intact α′ chain could be demonstrated on trypsin‐treated than on non‐treated schistosomula. Antibodies which were raised in rabbits by immunization with the trypsin‐released material bound to cultured (non‐treated) schistosomula and to adult worms, and induced their killing in GpS and C4‐deficient GpS. These results suggest that following release of the glycocalyx, the transforming schistosomula of S. mansoni spontaneously express a complement regulatory protein(s). A similar regulator is postulated to be present on the surface of adult worms. Such regulatory molecules may serve as good targets for immunotherapy, since antibodies directed to them will inhibit their regulatory activity and thus potentiate in vivo the lytic action of complement.
A new HLA‐DRB1 allele within the DRw52 supertypic specificity (DRw13‐DwHAG): Sequencing and direct identification by oligonucleotide typing
Authors: Tiercy Jean‐Marie , Jeannet Michel , Mach Bernard 
Published: March 2007

AbstractMolecular analysis of HLA class II polymorphism represents a crucial parameter for HLA matching in transplantation immunology, for the study of HLA‐disease association and for the understanding of major histocompatibility complex (MHC)‐restricted antigen presentation. We report here the DNA sequence and the deduced amino acid sequence of the polymorphic first domain exon of the DRB1 and DRB3 alleles of the homozygous cell line HAG (DRw13‐DwHAG‐DQw7). The DRB1 sequence represents a new DRB allele, which clearly shows a close relationship to other DRB1 genes from the DRw52 group and is now officially named DRB1*1303. The DRB1*1303 allele is very similar to the two DRw13 alleles we have described earlier, with only five amino acid differences at positions 32, 37, 47, 57 and 71. Furthermore, its sequence in the third hypervariable region is unique among all known DRB1 and DRB3 alleles. The sequence of the DRB3 gene of HAG shows that it corresponds to the previously described DRB3*0101 (DRw52a) allele. In addition we present analyses of a panel of healthy blood donors and leukemic patients by oligonucleotide typing showing that this new HLA‐DR specificity can now be unequivocally identified in routine oligotyping with an allele‐specific oligonucleotide probe.
Regulation of human IgE synthesis. I. Human IgE synthesis in vitro is determined by the reciprocal antagonistic effects of interleukin 4 and interferon‐γ
Authors: Chrétien Isabelle , Pène Jérǒme , Brière Francine , Malefijt René De Waal , Rousset Françoise , de Vries Jan E. 
Published: March 2007

AbstractIn the present study culture conditions resulting in optimal IgE synthesis by mononuclear cells (MNC) isolated from peripheral blood, tonsils or spleens from healthy nonallergic donors were investigated. The highest rate of IgE synthesis was obtained in a two‐step culture system in which the MNC were preincubated with interleukin 4 (IL4; 200 U/ml) for 48 h, washed and subsequently incubated with IL 4 (200 U/ml) for 9 days. Despite these culture conditions, IL4‐induced IgE synthesis varied considerably (1‐150 ng/ml) and MNC from 16/70 donors failed to produce IgE. Kinetic studies indicated that IL4 was required at the onset of the incubation phase. IgE synthesis was reduced by > 95% when addition of IL 4 in the incubation period was delayed 24 h or more. IL 4‐induced IgE synthesis was blocked by interferon‐γ (IFN‐γ). This inhibition is most effective when IFN‐γ was added in the 48‐h preincubation step or during the first 48 h of the incubation period. Interestingly, IL 4 was found to block spontaneous and lectin‐ or factor‐induced IFN‐γ production by MNC, purified CD3+, CD4+ or CD8+ Tcells. This down‐regulatory effect of IL 4 on IFN‐γ production occurred at the mRNA transcription level. Furthermore, it is shown that IL 4 induced the release of soluble CD23 and that recombinant soluble CD23 enhanced IL4‐ induced IgE synthesis, but only when IL 4 was present at suboptimal concentrations. Collectively, our data indicate that IL4 and IFN‐γ regulate the level of IgE synthesis by influencing each other's activities reciprocally during the first 3 days of the culture.
Structure of rearranged and germ‐line rabbit Vϰ genes indicated that the CDR3 is encoded by the Vϰ gene*
Authors: Ayadi Hammadi , Cazenave Pierre‐André , Marche Patrice N. 
Published: March 2007

AbstractThe third complementary‐determining regions (CDR3) of rabbit kappa chains are unusually long and the length is more heterogeneous when compared to those of the mouse and the human ϰ chains. To study how the rabbit ϰ light (L) chain genes create diversity and generate CDR3, we analyzed the structure of a rearranged variable ϰ gene (Vr) and the variable (Vg) and joining (Jg) regions of the putative precursor genes. Alignment of the Vr gene sequence with that of the Vg and Jg regions allowed precise determination of the recombination event. Five nucleotides between the recombination point and the J2 heptamer were deleted, indicating flexibility in the recombination producing rabbit ϰ chains. The entire Vg is contained in the rearranged product demonstrating that neither a D element nor an N sequence addition are required for the CDR3 formation. Comparison of the Vr and the Vg gene sequences show base substitutions suggesting that somatic mutations may contribute to rabbit ϰ L chain diversity.
Functional analysis of intercellular adhesion molecule‐1‐expressing human thyroid cells
Authors: Weetman Anthony P. , Freeman Mark , Borysiewicz Leszeck K. , Makgoba M. William 
Published: March 2007

AbstractWe have tested the potential role of thyroid cell intercellular adhesion molecule‐1 (ICAM‐1) expression by in vitro assays of cell clustering and cytotoxicity. Increased ICAM‐1 appeared within 24 h of thyroid cell stimulation with cytokines and was not inhibited by the antithyroid drug methimazole. Autologous and allogeneic lymphocyte‐thyroid cell cluster formation, assessed by flow cytometry, was reduced by about one‐third in the presence of a monoclonal antibody against ICAM‐1, regardless of whether thyroid cells were expressing basal levels of ICAM‐1 or had been stimulated with interferon‐γ. The cytotoxicity produced by interleukin 2‐stimulated allogeneic lymphocytes was not consistently inhibited by anti‐ICAM‐1 antibody, but phytohemagglutinin‐stimulated lymphocytes showed a reduction of 23% – 28% in cytotoxicity against untreated or interferon‐γ stimulated thyroid cells when the anti‐ICAM‐1 monoclonal antibody was present. Finally, thyroid cells could be infected by rhinovirus, confirming the presence of fully functional ligand. These results show that ICAM‐1 expression by thyroid cells may enhance immune cell recognition and play some role in cytotoxicity, features which could be important in the initiation or perpetuation of autoimmune thyroiditis.