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Henri Vacher-Coponat, Corinne Brunet,
Luc Lyonnet,
Elodie Bonnet,
Andersen Loundou,
José Sampol,
Valérie Moal,
Bertrand Dussol,
Philippe Brunet,
Yvon Berland,
Françoise Dignat-George,
Pascale Paul
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ABSTRACT: Natural killer (NK) cells provide a first line of immune defence towards infections and tumours, and participate in atherosclerosis and pregnancy diseases, of which there is a higher incidence in uraemic patients. Still, their relative contribution to the immunodeficient state associated with renal failure is poorly documented.
A multivariate and comparative analysis of lymphocyte subsets in haemodialysed (HD) and undialysed (UD) uraemic patients in comparison to healthy donors (HC) is provided in this article. NK-mediated cytotoxicity, degranulation and interferon secretion were compared in HD and HC.
Evaluation of NK cells in 210 HD patients concluded with a decrease in NK cell counts in comparison to HC. Multivariate analysis associated lowered NK cell counts in UD patients with decreased renal clearance and higher NK counts HD with male gender and age. The 32% NK cell count decrease observed in sex- and age-matched groups (n = 88) was associated with B- and CD8(+)T-lymphocyte defects. NK cell functions were similar in subgroups of HD and HC matched for NK cell counts. Longer dialysis duration was associated with improved NK cytototoxic activity. While the expression of receptors modulating NK cytotoxicity were not modified, expression of the activation markers CD69 and NKp44, CD94 and chemokine receptors CX3CR1 and CXCR4 was altered in HD.
This study is the first to associate decrease in renal function with selective fading of NK cell number and identify haemodialysis duration as a factor influencing NK cell function. It further shows that lower cell counts rather than intrinsic NK cell dysfunction per se characterize immune disorders in HD.
Nephrology Dialysis Transplantation 05/2008; 23(4):1406-14. · 3.40 Impact Factor
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Caroline Solas,
Nicolas Simon,
Marie-Pierre Drogoul,
Sylvie Quaranta,
Véronique Frixon-Marin,
Véronique Bourgarel-Rey, Corinne Brunet,
Jean-Albert Gastaut,
Alain Durand,
Bruno Lacarelle,
Isabelle Poizot-Martin
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ABSTRACT: The protease inhibitor indinavir is characterized by an important interindividual pharmacokinetic variability, which results from the actions of the metabolizing enzymes cytochrome P450 (CYP) 3A and the multidrug efflux pump P-glycoprotein (P-gp), encoded by MDR1. Using a population pharmacokinetic approach, we investigated the effect of several MDR1 and CYP3A5 polymorphisms on the pharmacokinetic parameters of indinavir in HIV-infected patients.
Twenty-eight patients receiving indinavir alone or together with ritonavir were included. Indinavir pharmacokinetics were studied over a 12 h interval. Genetic polymorphisms were assessed by real-time PCR assays and direct sequencing for MDR1 and by PCR-SSCP analysis for CYP3A5.
The pharmacokinetics of indinavir were best described by a one-compartment model with first-order absorption. In the final model, the MDR1 C3435T genotype and ritonavir were identified as statistically significant covariates (P </= 0.001) for the absorption rate constant (95% confidence interval on the difference between CC and CT genotype 0.37, 5.53) and for clearance (95% confidence interval on the difference 5.8, 26.2), respectively. Patients with the CYP3A5*3/*3 genotype receiving indinavir alone had a 31% decrease in the indinavir clearance rate compared with patients carrying the CYP3A5*1/*3 genotype.
The MDR1 C3435T genotype affects the absorption constant of indinavir suggesting that P-gp may be implicated in its pharmacokinetic variability. Through its inhibition of CYP3A and P-gp, ritonavir could attenuate the pharmacokinetic variability linked to genetic differences, reducing significantly the interindividual variability of indinavir. However, genotyping MDR1 and/or CYP3A5 to optimize protease inhibitor boosted regimens does not seem clinically relevant.
British Journal of Clinical Pharmacology 10/2007; 64(3):353-62. · 2.96 Impact Factor
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Henri Vacher-Coponat, Corinne Brunet,
Valérie Moal,
Andersen Loundou,
Elodie Bonnet,
Luc Lyonnet,
Sophie Ravet,
Emmanuelle Sampol-Manos,
José Sampol,
Yvon Berland,
Françoise Dignat George,
Pascale Paul
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ABSTRACT: Recently introduced immunosuppressive drugs are more potent to control graft rejection, but current concerns are raised regarding their potential to increase long-term neoplastic and infectious complications. Considering the role of B, T, or natural killer (NK) lymphocyte in controlling alloreactive, anti-infectious, and antitumoral immune responses, we compared the impact of two immunosuppressive regimens on lymphocyte subsets one year following kidney transplant.
Multivariate regression analysis of variables affecting lymphocyte subset counts was retrospectively performed on 91 kidney-transplanted patients, analyzed before graft, at day 15 and 1-year postgraft. These patients were included in a randomized prospective open trial comparing tacrolimus/mycophenolate mofetil (FK/MMF) versus cyclosporine/azathioprine (CSA/Aza), both used in association with rabbit antithymocyte globulines (rATG) induction and prednisone.
Fifteen days postgraft, severe T and NK lymphocyte depletion were observed in all patients, while B cell counts were selectively higher in the FK/MMF group as compared to before graft. One-year posttransplant, NK cell counts and NK cell cytotoxicity was significantly higher in patients receiving FK/MMF therapy, as compared to CSA/Aza. Cytomegalovirus (CMV) infection during the first year posttransplant was also associated to higher NK, CD8, and CD4CD8 T cell counts at month 12.
In addition to its higher potential in preventing graft rejection, we show that after one year of transplant, FK/MMF better preserves NK innate immune effector cells and their cytotoxic potential. These data prompt to further evaluate the role of NK cells in relation to antiviral and tumoral surveillance of transplanted patients, which are common complications of long-term immunosuppression.
Transplantation 09/2006; 82(4):558-66. · 4.00 Impact Factor
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Véronique Pascal,
Nicolas Schleinitz, Corinne Brunet,
Sophie Ravet,
Elodie Bonnet,
Xavier Lafarge,
Mhammed Touinssi,
Denis Reviron,
Jean Francois Viallard,
Jean Francois Moreau,
Julie Déchanet-Merville,
Patrick Blanco,
Jean Robert Harlé,
José Sampol,
Eric Vivier,
Françoise Dignat-George,
Pascale Paul
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ABSTRACT: We have characterized the heterogeneity of human blood NK cell subsets defined by expression of KIR, lectin like receptors and NK cell differentiation markers within a cohort of 51 healthy Caucasian individuals. High inter-individual variability in cell surface expression of most NK cell markers is observed. Range values defining NK cell subsets in healthy donors were further used as references to characterize 14 patients with NK-type lymphoproliferative disease of granular lymphocytes (NK-LDGL). Alterations of the KIR repertoire were noted in all NK-LDGL patients. NK cell expansions were classified as oligoclonal KIR(+) or as non-detectable KIR ((nd)KIR) using anti-KIR2DL1/2DS1, anti-KIR2DL2/2DL3/2DS2, anti-KIR3DL1 and anti-KIR2DS4 monoclonal antibodies. A major reduction in the size of the CD56(bright) NK cell subset was a constant feature of NK-LDGL. Altered distribution of CD94(+), CD161(+), and CD162R(+) NK cell subsets was also observed in NK-LDGL patients. Considering the potential role of NK cells in eliminating tumors or virus-infected cells, the reference values defined in this study should be valuable to characterize both quantitative and qualitative alterations of the NK cell repertoire in pathological conditions and to monitor NK cell reconstitution following hematopoietic transplantation.
European Journal of Immunology 11/2004; 34(10):2930-40. · 5.10 Impact Factor
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ABSTRACT: Autoimmune hemolytic anemia (AIHA) is rare and difficult to treat during chronic hepatitis C. We report herein the case of a hepatitis C patient with severe and resistant AIHA who experienced a good and sustained response with anti-CD20 monoclonal antibody treatment.
American Journal of Hematology 05/2004; 75(4):243-5. · 4.67 Impact Factor
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Haematologica 12/2002; 87(11):ECR35. · 6.42 Impact Factor
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Marc Maynadié,
Luc Gerland,
Serge Aho,
François Girodon,
Michel Bernier, Corinne Brunet,
Lydia Campos,
Sylvie Daliphard,
Véronique Deneys,
Annie Falkenrodt,
Marie-Christine Jacob,
Emilienne Kühlein,
Geneviève LeCalvez,
Philippe Moskovtchenko,
Patrick Philip,
Paule-Marie Carli,
Gilbert C Faure,
Marie-Christine Béné
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ABSTRACT: The various epitopes of the CD34 molecule have been classified according to their different sensitivities to enzymatic cleavage by neuraminidase, chymopapain and a glycoprotease from Pasteurella haemolytica. Although monoclonal antibodies have been developed that specifically identify these epitopes, few studies have evaluated the distribution and quantitative expression of such epitopes on leukemic blasts.
We report here a prospective multicenter study in which we examined and quantified the expression of the 3 classes of CD34 on fresh leukemic blast cells from 300 cases of acute myeloid leukemia (AML). The binding of monoclonal antibodies was studied by flow cytometry, allowing evaluation of blast cell positivity as well as their mean fluorescence intensity. These quantitative data were made comparable between centers by means of a calibration curve established with the same reagents in all laboratories.
Quantitative expression of class I epitope was significantly higher than that of class II and class III epitopes (p<0.0001). The three classes were more frequently expressed in M0 and M1 and less in M3 and M5. The highest levels of CD34 expression were observed in M2, M0 and M1 and the lowest in M3, M5 and BAL for class II and III. CD34 expression was lower for all classes in cases with a normal karyotype, compared to in cases with structural or numerical abnormalities.
In cases with a t(9;22) the expression of class I was significantly higher than that of class II and III and the opposite was observed in AML with t(15;17). Moreover, as a whole, a high intensity of class III CD34 appeared to be a marker of good prognosis.
Haematologica 08/2002; 87(8):795-803. · 6.42 Impact Factor
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The Hematology Journal 02/2002; 3(4):216-8. · 1.86 Impact Factor
