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Six human T lymphomas and an NK-like cell line were tested for their ability to produce HILDA, one of the two human growth promoting activities for the DA1.a cells. Among them, the HSB2 cell line turned out to be the only one secreting significant HILDA activity (200-400 units/ml) after activation with 50 nM phorbol myristate acetate. Subclones of the HSB2 cell line were obtained by limiting dilution experiments. One of them (2B3) was found to secrete 1,000-5,000 units/ml of HILDA after phorbol myristate acetate activation in the presence of 10% fetal calf serum and 200-500 units/ml in serum-free conditions. 2B3-HILDA was purified from serum-free conditioned medium by a four-step procedure including fast flow cationic exchange at pH 6, concanavalin A chromatography, reverse-phase high performance liquid chromatography and gel-filtration high performance liquid chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the purified radiolabeled cytokine revealed a single band of Mr 43,000, which co-electrophoresed with the biological activity. The NH2-terminal amino acid sequence of the first residues of the protein were determined and found to be similar to the equivalent residues deduced from the molecularly cloned cytokine. Isoelectric point determination revealed some charge heterogeneity of HILDA, which focused to pH 8.5-9 after neuraminidase treatment. Carbohydrate content of the cytokine was studied by deglycosylation experiments which showed that the O-linked oligosaccharides represented 2,000-3,000 and that the N-linked sugars account for half of the apparent molecular weight of HILDA.

The aim of this study was to define as possible abnormality of interleukin 2 (IL2) production by PHA-stimulated peripheral blood lymphocytes (PBL) in systemic lupus erythematosus (SLE). Thirty-four SLE PBL samples were stimulated to produce IL2 and compared with PBL from healthy (age- and sex-matched) controls. A significant defect in IL2 production was observed in SLE patients. This defect was not restricted to corticosteroid-treated patients and was not correlated with the presence of lymphotoxic antibodies or with clinical disease activity. Although 5-day responsiveness to phytohaemagglutinin (PHA) decreased in SLE, the SLE PHA-blasts responded as well as control blasts to semipurified IL2, suggesting that the receptor for IL2 was normally expressed on SLE blasts. In 9 cases, the effect of addition of indomethacin (2 micrograms/ml) or of an optimal amount of IL1 on PHA-induced IL2 production was studied. Indomethacin increased (22%) the IL2 yield of healthy individual PBL. In SLE, indomethacin (but not IL1) was able to completely restore (41% increase) the IL2 production of lectin-stimulated PBL (P less than 0.01). These data suggest that, in SLE, the inhibition of IL2 production is mediated by prostaglandin, possibly produced by monocytes.

Repeated analysis of peripheral blood lymphocytes (PBLs) from a patient with large granular lymphocytosis, neutropenia, and rheumatoid arthritis revealed that approximately 45% of PBLs displayed the following phenotype: CD3+, CD4-, CD8-, CD16+, HNK-1-, WT31-. This population was purified for further analysis by depletion with anti-CD4 and anti-CD8 monoclonal antibodies (MoAbs). Southern blot analysis showed preferential rearrangements of the V gamma 9 genes. Northern blot demonstrated the presence of V gamma 9 mRNA transcripts. With MoAbs directed against either the V gamma 9 peptide (Ti gamma A) or the delta chain of the gamma delta T-cell receptor (TCR delta 1), we further demonstrated that those cell surfaces expressed both V gamma 9 and a delta gene product. In addition, analysis of the gamma gene rearrangements on six clones derived from this population demonstrated a unique rearrangement on a single chromosome, strongly suggesting the monoclonality of this T-cell population. Significant cytotoxic activity against K562, U937 was observed only after an in vitro culture period with interleukin-2 (IL-2), whereas no specific inhibitory effect on autologous bone marrow (BM) CFU-G was noted.

Several suggar can strongly inhibit the natural cytotoxicity (NK) exhibited by peripheral blood lymphocytes (PBL) against tumour cells. The inhibition of NK cytotoxicity mediated by mannose, glucose, galactose and saccharose was tested in human PBL. All these suggar significantly blocked (P < 0.01 at 50 mM concentration) the NK cytotoxicity. The blocking is dose-dependent in a linear pattern. The sole preincubation of the attacking (NK) population is required for inhibition of cytotoxicity; no influence of the suggar were noticed on the K562 alone. In contrast, the NK cytotoxicity of PBL primed in mixed lymphocyte reaction and further cultured in presence of conditioned mediam (CM), showed, aside of a clear increase (average 40% increase of specific 51Cr release, P < 0.05) a full insensitivity to the tested suggar. Phytohaemagglutinin (PHA), interferon (IF) and an interleukin 2 (II2) are contained in the CM. We showed that neither the PHA nor the IF preincubation of the cells can induce the insensitivity of NK for the suggar, thus our data strongly suggest that II2 is implicated in the sugar insensitivity of the cytotoxicity of lymphocytes cultured with CM.

Rearrangements of the T-cell Rearranging Gene (TRG) or T-cell-receptor gamma-chain genes were analyzed in 24 in vivo-sensitized alloreactive T-cell clones. This analysis represents the first complete assignment of TRG gene rearrangements to given variable and joining gene segments in nonleukemic T cells and provides some evidence for the hypothesis of sequential gamma genes rearrangements during T-lymphocyte differentiation. TRG gene rearrangements in our T-cell panel involved the known "active" V gamma genes, with a preferential use of V2 and V4 genes. In most clones, rearrangements occurred on both chromosomes and involved the J2 segment, but only 2 and 4 out of the 49 described rearrangements involved the additional J gamma segments JP1 and JP2, respectively. Two peculiar rearrangements were found. The first one was probably due to the creation of a new restriction enzyme site in the N-region at the V-J junction; the second can be explained by an aberrant rearrangement of a V gene to a sequence located between exons 2 and 3 of the TRGC1 gene.

The expression of HLA-DR epitopes, recognized by a set of anti-DR MoAbs clustered into four groups according to immunochemical studies, was analyzed at the surface of in vivo-sensitized alloreactive T-cell clones derived from a rejected kidney allograft and on the autologous B lymphoblastoid cell line (BLCL). Although no clear-cut differences were noted between T cells themselves and T cells vs BLCL in the relative expression of most of the DR epitopes studied (D1.12, BT2/9, VI.15C, 135, 206, 141, BM50), relative and absolute expression of one DR epitope (BMMag8) was strikingly higher on autologous BLCL than on T-cell clones. Moreover, the absolute expression of DR epitopes was heterogeneous among T cells. Such differences could not be explained either by T-cell activation level (assessed by IL2 receptor or transferrin receptor expressions) or by differences in time kinetics expression. In other tests, anti-DR MoAbs were assayed for their ability to block cytotoxic activity of several T-cell clones directed against DR allospecificities. Each T-cell clone showed distinct inhibition patterns. By such analysis, it was possible to define several groups of epitopes not always identical to those defined by immunochemical studies. Finally, analysis of the ability of MoAb to specifically block cytotoxicity mediated by 2 anti-DRw8 T-cell clones at the target level allowed precise epitopic study of polymorphic DRw8 determinants recognized by these cells, in this case borne by a single DR alpha/beta heterodimer.

The aim of our study was to evaluate the function and growth of parathyroid tissue autografted into the forearm of hemodialysis patients using several presently available methods. In a dynamic study, the secretory function of autografted tissue was evaluated in seven patients using either zero calcium dialysate or calcium infusion. In an additional prospective study, seven patients had repeated determinations of plasma immunoreactive parathyroid hormone (iPTH) concentration on samples from both forearms, a radionuclide evaluation of autograft function using thallium-201 chloride, and real time ultrasonography. Light microscopy analysis was performed in two patients. The dynamic study demonstrated that induction of hypocalcemia was followed by an increase, and induction of hypercalcemia by a decrease, in circulating iPTH in both forearms using three different radioimmunoassays, similar to what has been reported for normal parathyroid tissue. A significant gradient (ie, greater than 2.0) of plasma iPTH concentration in samples from both forearms was observed in only three out of the seven patients of the prospective study. Two of these patients disclosed an increased uptake of 201TI chloride at the site of autografted tissue and had an echographically detectable mass. In both, hyperplastic parathyroid tissue was removed. At present, the remaining third patient does not have other features of recurrent hyperparathyroidism. In conclusion, autotransplanted parathyroid tissue of hemodialysis patients shows an adequate response to physiologic stimuli such as hypo- and hypercalcemia. Dynamic tests, therefore, appear to be a useful tool in the assessment of its function. In addition, radionuclide and echographic studies may be reliable adjuncts in the detection of marked parathyroid autograft hyperplasia.

Interleukin 2 production by peripheral blood lymphocytes in allograft recipients during acute rejection episodes. Inthis study we investigate the relationship between the Interleukin 2 (IL-2) yield produced by kidney allograft recipient's peripheral blood lymphocytes (PBL) under lectin stimulation and the occurrence of acute rejection episodes. PBL were harvested prospectively before grafting, after grafting in steady-state period, and at the onset of acute rejection episodes. In addition, we tested retrospectively the ability of PBL of recipients engrafted for more than 1yr to produce IL-2. IL-2 levels were assessed on the IL-2-dependent CTL-L2 murine cell line. Our data show: 1) before grafting, hemodialysed patients (N = 14) produced normal IL-2 yield compared with healthy donors (N = 21); 2) the IL-2 secretion of PBL ofrecipients with good graft function (N = 18) is decreased markedly during roughly the first 12 months following transplantation (P < 0.01); 3) when acute rejection crisis occurred during this time period (N = 24), a sharp and highly significant increment (P < 0.01) in lectin-induced IL-2 production of recipient's PBL was seen. After 1 yr, the capacity to secrete IL-2 upon lectin stimulation tends to be restored. Finally, our data correlate rejection and high PBL-IL-2 secretion clearly at a time when recipients with well-functioning grafts have markedly impaired IL-2 secretion.

The effect of cyclosporine and metabolite 17 (M17) as well as other CsA-related compounds (CsG, dihydro-CsC, dihydro-CsD, CsH, B5.49, and H7.94) was tested on T lymphocyte clone proliferation. In these experiments, antigen and interleukin 2 (IL-2) dependent long-term T lymphocyte clones derived from a rejected human kidney graft infiltrate were used. They were specifically committed (proliferation and cytotoxicity) for the donor Epstein-Barr virus (EBV)-transformed cells. CsA strongly inhibited clone T cell proliferation induced by the antigen. Inhibition of antigen-driven proliferation was reversed by pure recombinant IL-2 (rec-IL-2) only when low amounts of CsA (less than 25 ng/ml) were used, whereas this lymphokine was ineffective at higher but still pharmacological CsA concentrations (50-500 ng/ml). Increasing rec-IL-2 concentrations did not modify this finding. In addition, CsA, did not inhibit the growth signal(s) induced by rec-IL-2/IL-2 receptor interactions when R-IL-2 is pre-expressed on clone cells. M17 was far less effective in inhibiting antigen-induced clone cell proliferation (50% inhibition at 16 ng/ml versus 500 ng/ml with, respectively, CsA and M17) but was nevertheless inhibitory. This observation, if extended to other metabolites, could be important for interpretation of the relevance of "CsA" concentration through radio-immunoassay monitoring of recipients' blood. Although CsA appeared to display the major inhibitory effect, dihydro-CsC and CsG, as well as B5.49 and H7.94 CsA-related compounds, also exhibited strong activity. Dihydro-CsD was less inhibitory, and CsH had no effect.

Cellular mechanisms involved in the allograft rejection process remain highly controversial. Using monoclonal antibodies, several studies have demonstrated convincingly that most of the infiltrating mononuclear cells are T lymphocytes. Moreover, several investigators have developed techniques for culturing T cells out of various human allografts in order to delineate functions of intragraft T-cell populations.

Ce texte présente un exemple de la pratique d’intervention de l’AGASP, groupe de travail créé en 1971 par Gérard Mendel, psychanalyste et anthropologue, pour alimenter ses travaux théoriques et les mettre à l’épreuve de la réalité institutionnelle. Ce type de réalisation au long cours (vingtième année), s’appuyant sur la mise en oeuvre d’une méthodologie précise, montre qu’une nouvelle pratique sociale modifiant l’organisation du travail est possible dans le cadre d’organisations traditionnelles. Cette démarche vise à améliorer la coopération, tout en permettant aux acteurs de vivre un rapport plus enrichissant à leur acte de travail et, ainsi, de développer leur psychosocialité., This article presents an example of the intervention practice of AGASP, a working party created in 1971 by Gérard Mendel, a psychoanalyst and anthropologist, to sustain and put to the test of institutional reality his theoritical work. This type of long run realization (twentieth year of application), based on the implementation of a precise methodology, shows that a new form of social practice modifying work organization is possible in the context of traditional organizations. This procedure aims at improving cooperation while permitting actors to live a more enriching relation to their “work act” and, thus, develop their “psychosociality”.

International audience; Hormis le travail de réduction et de façonnage d’objets en or et en alliages cuivreux en Amérique du sud et centrale [2] et le travail à froid de cuivre natif autour des Grands Lacs nord américains [4], les populations amérindiennes n’ont généralement connu les objets métalliques qu’à partir de la « découverte » des Amériques par les Européens. Dans le Nord-est de l’Amérique du Nord (Nouvelle-Angleterre, Ontario et Québec méridionaux), des objets en métal (principalement, chaudrons en alliages à base de cuivre (ABC) [5], couteaux et haches en fer) et d’autres « commodités » (perles en verre, par exemple) sont obtenus des Européens par les Amérindiens en échange des fourrures (surtout le castor) que trappent ces derniers.Les caractérisations élémentaires par activation neutronique d’un ensemble de fragments de chaudron en ABC trouvés lors des fouilles d’une couche amérindienne antérieure [6] au poste de traite établi à Chicoutimi (actuelle ville de Saguenay, Québec) au cours du troisième quart du XVIIe siècle ainsi que d’un autre ensemble de fragments provenant de sépultures amérindiennes mises au jour au site Grimsby (Ontario) [7] du second quart du XVIIe siècle ont déjà fait l’objet de publications. Ce travail vise à rapporter les résultats des observations des coupes métallographiques observées en microscopies optique et électronique à balayage de ces deux ensembles [8]. De surcroît, ces mêmes fragments seront comparés par les mêmes méthodes microscopiques à une série de fragments datés du XVIIe siècle trouvés lors de travaux archéologiques menés récemment à Bordeaux. D’ores et déjà, le contexte amérindien de chaudrons obtenus par le biais de la traite des fourrures suggère un certain degré d’homogénéité de ces contenants puisque aucun autre type d’objet de cuivre n’est échangé. Au contraire, les objets mis au jour sur la place de la Bourse à Bordeaux [3] devraient présenter une hétérogénéité plus sensible, les fragments à l’étude n’appartenant pas, selon toute vraisemblance à la seule catégorie des chaudrons. Les observations microscopiques des deux séries de fragments provenant du Nord-est nord-américain sont aussi susceptibles de préciser dans quelle mesure le travail à froid des chaudrons (ceux-ci ayant achevé leur vie utile comme contenants : perçage découlant, notamment, de leur utilisation sur feu à ciel ouvert) par les populations amérindiennes peut être observé sur les coupes métallographiques [1]. Les observations microscopiques des fragments de Bordeaux devraient, quant à elles, nous fournir un éventail des techniques de façonnage utilisées pour le travail du cuivre et de ses alliages au cours du XVIIe siècle.En somme, si liminaire soit-elle, cette étude des objets en ABC, veut établir un pont entre la côte occidentale de l’Europe et la côte orientale de l’Amérique du Nord susceptible de préciser les modalités de transferts culturels, notamment au chapitre des techniques de production des objets en ABC.Références en ordre alphabétique[1] Ehrhardt, K.L., 2005, European Metals in Native Hands: Rethinking Technological Change 1640-1683, University of Alabama Press, 272 p.[2] Fraresso, C., 2007, L’Usage du métal dans la parure et les rites de la culture Mochica (150-850 ap. J.C., Pérou, Thèse, Doctorat physique des archéomatériaux, Université Michel de Montaigne Bordeaux, 578 p. [3] Gerber F. (dir), 2006, RFO de Fouille préventive. Chantiers archéologiques « Bourse, Saint Rémi, Jean Jaurès et Gabriel », INRAP, Aquitaine, Gironde, Bordeaux, 12 livres en format PDF.[4] Martin, S. (1999). Wonderful power: The story of ancient copper working in the Lake Superior Basin. Detroit: Wayne State University Press, 272 p.[5] Moreau, J.-F & R.G.V. Hancock, 1999, « Faces of European copper alloy cauldrons from Québec and Ontario «contact» sites ». In Young, Suzanne M.M., Pollard, A.Mark, Budd, Paul & Ixer, Robert A. (dir.), Metals in Antiquity, Oxford, Archaeopress, BAR International series nº 792, pp. 326-340.[6] Moreau, J.-F & R.G.V. Hancock, 2010, « ‘Un siècle d’approvisionnement : 1550-1650’ : de la préhistoire à l’histoire au site du poste de traite de Chicoutimi », Archéologiques, vol. 23, p. 84-98.[7] Moreau, J.-F & R.G.V. Hancock, M. Pernot, F. Daniel, M. Kapches, 2009, «The copper-based cauldrons from the Grimsby site (Onta rio, Canada) : INAA and preliminary observati ons under optical and electron scanning microscopes» in Moreau, J.-F., R.Auger, J. Chabot & A.Herzog (dir.), 2009, Proceedings./Actes 36th International Symposium of Archaeometry/36e Symposium International d’Archéométrie, May 2nd - 6th, 2006 Quebec City, Canada, Québec, Université Laval, CELAT, Série archéologique, No 24 coll. Archéométrie No 7, p.485-493.[8] Pernot M., 1999a, «La métallographie», dans R. Meyer-Roudet (dir.), A la recherche du métal perdu – Les nouvelles technologies dans la restauration des métaux archéologiques, Musée archéologique du Val d'Oise, Errance, Paris, p. 65-67.

Spiroplasma citri est une bactérie phytopathogène transmise par la cicadelle Circuliferhaematoceps. L'absence de symptômes malgré la multiplication de S. citri dans l'hémolymphe, suggèreque le système immunitaire joue un rôle important dans la tolérance de la cicadelle vis-à-vis duspiroplasme.Le but de cette thèse a donc été d'étudier la réponse immunitaire de C. haematoceps aucours de l'infection par S. citri.Notre étude sur le système immunitaire de la cicadelle a montré la présence dans le plasma d'uneactivité antibactérienne et d'une activité phénoloxidase. Parmi les principaux types d'hémocytes unephagocytose des bactéries par les granulocytes et les plasmatocytes a été observée. Les gènessusceptibles d'être impliqués dans ces processus ont été recherchés par une approche par hybridationsoustractive. De manière étonnante, aucun gènes codant des récepteurs ni d'effecteurs connus del'immunité n'ont été identifiés. En revanche certains gènes (23 en tout) codent des protéines ayantpotentiellement un rôle immunitaire. Six de ces 23 gènes ont été retenus pour suivre leur expressionau temps précoce d'une infection bactérienne. Les résultats ont montré que les gènes codantI'Hexamérine, la DDBPl et la Thiorédoxine peroxydase étaient surexprimés lors de l'infection par 5.citri. Une approche fonctionnelle d'interférence par ARN a montré d'une part que I'Hexamérine étaitimpliquée dans l'activité phénoloxidase et d'autre part qu'elle jouait un rôle important dans la surviede C. haematococeps au cours de l'infection par 5. citri. En parallèle, le suivi de l'activité phénoloxidaseet de la phagocytose au cours de l'infection a montré que 5. citri était capable de s'adapter à laréponse immunitaire de l'insecte et d'y échapper. Ces résultats rejoignent ceux obtenus chez ladrosophile concernant S. poulsonii., Spirop/asma citri is phytopathogenic bacteria transmitted by the leafhopper Circuliferhaematoceps. The absence of symptoms despite the multiplication of S. citri in the hemolymph,suggests that the immune system plays an important role in the tolerance of the leafhopper towardsthe spiroplasma infection. The purpose of this thesis was to study the immune response of C.haematoceps during the infection by 5. citri.The characterization of the immune system of the leafhopper showed that an antibacterial activity anda phenoloxidase activity were present in the plasma. The main types of hemocytes were identified.Among them, granulocytes and plasmatocytes are capable to phagocyte bacteria. The genes involvedin these immune processes were searched using subtractive hybridization method. lnterestingly, noneof the genes known to encode receptors or effectors of the immune system were identified. On theother hand 23 putative immune genes were identified. Six of these genes were retained to follow theirexpression in the early time of a bacterial infection. The results showed that the genes encodingHexamerin, DDBPl and Thioredoxin peroxidase were up-regulated during the infection by 5. citri. Afunctional approach by gene silencing showed that Hexamerin was involved in the phenoloxidaseactivity and played an important role in the survival of C. haematoceps during the infection by S. citri.Finally, the follow-up of the phenoloxidase activity and phagocytosis by hemocytes showed anadaptation and an evasion of S. citri from the immune response of the insect, according to the resultsobtained for 5. pou/sonii-infected drosophila.Keywords : 5piroplasma citri, phenoloxidase, phagocytosis, hemocytes, gene silencing, Hexamerine,subtractive hybridization.

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