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1. Performances of two rapid LAMP-based techniques for the intrapartum detection of Group B Streptococcus vaginal colonization

Author

Rym Charfi, Cécile Guyonnet, Meiggie Untrau, Gaëlle Giacometti, Thierry Paper, Claire Poyart, Céline Plainvert, and Asmaa Tazi

Subjects
Group B Streptococcus, Intrapartum screening, NAAT, Neonatal infection, LAMP, Therapeutics. Pharmacology, RM1-950, Infectious and parasitic diseases, RC109-216, Microbiology, QR1-502
Abstract

Abstract Purpose Group B Streptococcus (GBS) is the leading cause of invasive infections in newborns. The prevention of GBS neonatal disease relies on the administration of an intrapartum antibiotic prophylaxis to GBS-colonized women. In recent years, rapid intrapartum detection of GBS vaginal colonization using real-time nucleic acid amplification tests (NAATs) emerged as an alternative to antenatal culture screening methods. Methods We compared the performances of two loop-mediated isothermal amplification (LAMP) tests, the Ampliflash® GBS and the PlusLife® GBS tests, to standard culture for GBS detection in vaginal specimens from pregnant women. The study was conducted from April to July 2023 in a French hospital of the Paris area. Results A total of 303 samples were analyzed, including 85 culture-positive samples (28.1%). The Ampliflash® GBS test and the PlusLife® GBS tests gave a result for 100% and 96.3% tests, respectively. The performances of the tests were as follows: sensitivity 87.1% (95% confidence interval (CI) 78.3–92.6) and 98.7% (95% CI 93.0-99.8), specificity 99.1% (95% CI 96.7–99.8), and 91.9% (95% CI 87.3–95.0), respectively. False negative results of the Ampliflash® GBS test correlated with low-density GBS cultures. Time-to-results correlated with GBS culture density only for the PlusLife® GBS test (p

Published
2024
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2. Matching for the nonconventional MHC-I MICA gene significantly reduces the incidence of acute and chronic GVHD

Author

Christophe Picard, Cécile Macquin, Sergi Querol, Catherine Paillard, Katharina Fleischhauer, Gaëlle Giacometti, Bronno van der Holt, Ibrahim Yakoub-Agha, Wassila Ilias, Anne Cesbron, Myriam Labopin, Masao Ota, Jorge Sierra, Fabio Ciceri, Dominique Charron, Ryad Tamouza, Régis Peffault de Latour, Xavier Lafarge, Katia Gagne, Seiamak Bahram, Myriam Maumy-Bertrand, Meiggie Untrau, Pascale Loiseau, Raphael Carapito, Jürgen Kuball, Bruno Lioure, Frans H.J. Claas, Noel Milpied, Antoine Toubert, Jan J. Cornelissen, Irina Kotova, Philippe Moreau, Eric Spierings, Mauricette Michallet, Arnon Nagler, Annette Schmitt-Graeff, Angélique Pichot, Petya Apostolova, Mohamad Mohty, Aurore Morlon, Myriam Labalette, Nicolas Jung, Didier Blaise, Yoshihiko Katsuyama, Hidetoshi Inoko, A. Parissiadis, Frédéric Bertrand, Marius Kwemou, Sandra Michel, Machteld Oudshoorn, Gérard Socié, Robert Zeiser, Peter A. von dem Borne, Valérie Dubois, Luca Vago, Carapito, Raphael, Jung, Nicola, Kwemou, Mariu, Untrau, Meiggie, Michel, Sandra, Pichot, Angélique, Giacometti, Gaëlle, Macquin, Cécile, Ilias, Wassila, Morlon, Aurore, Kotova, Irina, Apostolova, Petya, Schmitt Graeff, Annette, Cesbron, Anne, Gagne, Katia, Oudshoorn, Machteld, Van Der Holt, Bronno, Labalette, Myriam, Spierings, Eric, Picard, Christophe, Loiseau, Pascale, Tamouza, Ryad, Toubert, Antoine, Parissiadis, Anne, Dubois, Valérie, Lafarge, Xavier, Maumy Bertrand, Myriam, Bertrand, Frédéric, Vago, Luca, Ciceri, Fabio, Paillard, Catherine, Querol, Sergi, Sierra, Jorge, Fleischhauer, Katharina, Nagler, Arnon, Labopin, Myriam, Inoko, Hidetoshi, Von Dem Borne, Peter A., Kuball, Jürgen, Ota, Masao, Katsuyama, Yoshihiko, Michallet, Mauricette, Lioure, Bruno, De Latour, Régis Peffault, Blaise, Didier, Cornelissen, Jan J., Yakoub Agha, Ibrahim, Claas, Fran, Moreau, Philippe, Milpied, Noël, Charron, Dominique, Mohty, Mohamad, Zeiser, Robert, Socié, Gérard, Bahram, Seiamak, inconnu, Inconnu, Institut de Recherche Mathématique Avancée (IRMA), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Immuno-Rhumatologie Moléculaire, Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Laboratoire de Mathématiques et Modélisation d'Evry (LaMME), Institut National de la Recherche Agronomique (INRA)-Université d'Évry-Val-d'Essonne (UEVE)-Centre National de la Recherche Scientifique (CNRS), laboratoire d'Etudes et de recherches en Statistiques et Développement (LERSTAD), Université Gaston Bergé Sénégal, Laboratoire d'Acoustique Environnementale (IFSTTAR/AME/LAE), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université de Lyon-PRES Université Nantes Angers Le Mans (UNAM), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), LabEx Transplantex [Strasbourg], Université de Strasbourg (UNISTRA), Etablissement Français du Sang [Nantes], Etablissement Français du Sang - Alpes-Méditerranée (EFS - Alpes-Méditerranée), Etablissement Français du Sang, Service de pneumologie [Rennes] = Pneumology [Rennes], CHU Pontchaillou [Rennes], Anthropologie bio-culturelle, Droit, Ethique et Santé (ADES), Aix Marseille Université (AMU)-EFS ALPES MEDITERRANEE-Centre National de la Recherche Scientifique (CNRS), Alloimmunité-Autoimmunité-Transplantation (A2T), Institut Universitaire d'Hématologie (IUH), Université Paris Diderot - Paris 7 (UPD7)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM), Hématologie -Immunologie -Cibles thérapeutiques, Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM), Hôpital Saint-Louis, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Diderot - Paris 7 (UPD7), Sociétés, Acteurs, Gouvernement en Europe (SAGE), Politique, Religion, Institutions et Sociétés : Mutations Européennes - Groupe de Sociologie Politique Européenne (PRISME-GSPE), Centre National de la Recherche Scientifique (CNRS), Centre de Transfusion Sanguine Aquitaine-Limousin (CTS AQUITAINE-LIMOUSIN), Centre de Transfusion Sanguine, Ospedale San Raffaele, Université Pierre et Marie Curie - Paris 6 - UFR de Médecine Pierre et Marie Curie (UPMC), Université Pierre et Marie Curie - Paris 6 (UPMC), Barcelona Cord Blood Bank, Agrosystèmes tropicaux (ASTRO), Institut National de la Recherche Agronomique (INRA), Chaim Sheba Medical Center [Ramat Gan, Israel], CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Hôpital Edouard Herriot [CHU - HCL], Hospices Civils de Lyon (HCL), Département d'Oncologie et Hématologie [Strasbourg], Les Hôpitaux Universitaires de Strasbourg (HUS), Université Paris Diderot - Paris 7 (UPD7), Erasmus University Medical Center [Rotterdam] (Erasmus MC), Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Department of Immunohematology and Blood Transfusion, Leiden University Medical Center (LUMC), Universiteit Leiden-Universiteit Leiden, Centre hospitalier universitaire de Nantes (CHU Nantes), Centre d'Investigations Biomédicales-Hématologie, Oncologie et Greffes (CIB-HOG), Hôpital St Louis, Assistance Publique des Hôpitaux de Paris (AP-HP), Centre d'Investigations Biomédicales-Hématologie, Institut National de la Recherche Agronomique (INRA)-Université d'Évry-Val-d'Essonne (UEVE)-ENSIIE-Centre National de la Recherche Scientifique (CNRS), Service de pneumologie, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-CHU Pontchaillou [Rennes], Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), ALWP-EBMT & Département d'hématologie et de thérapie cellulaire [AP-HP Hôpital Saint-Antoine], AP-HP - Hôpital Saint-Antoine, Hematology, Institut de Recherche Mathématique Avancée ( IRMA ), Université de Strasbourg ( UNISTRA ) -Centre National de la Recherche Scientifique ( CNRS ), Université de Strasbourg ( UNISTRA ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ), Laboratoire de Mathématiques et Modélisation d'Evry ( LaMME ), Institut National de la Recherche Agronomique ( INRA ) -Université d'Évry-Val-d'Essonne ( UEVE ) -ENSIIE-Centre National de la Recherche Scientifique ( CNRS ), laboratoire d'Etudes et de recherches en Statistiques et Développement ( LERSTAD ), Laboratoire d'Acoustique Environnementale ( IFSTTAR/AME/LAE ), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux ( IFSTTAR ) -Université de Lyon-PRES Université Nantes Angers Le Mans ( UNAM ), Laboratoire d'Histoire des Sciences et de Philosophie - Archives Henri Poincaré ( LHSP ), Université de Lorraine ( UL ) -Centre National de la Recherche Scientifique ( CNRS ), Physique des interactions ioniques et moléculaires ( PIIM ), Aix Marseille Université ( AMU ) -Centre National de la Recherche Scientifique ( CNRS ), Functional Genomics and Cancer, Etablissement Français du Sang - Alpes-Méditerranée ( EFS - Alpes-Méditerranée ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -CHU Pontchaillou [Rennes], Anthropologie bio-culturelle, Droit, Ethique et Santé ( ADES ), Aix Marseille Université ( AMU ) -EFS ALPES MEDITERRANEE-Centre National de la Recherche Scientifique ( CNRS ), Alloimmunité-Autoimmunité-Transplantation ( A2T ), Université Paris Diderot - Paris 7 ( UPD7 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ), Assistance publique - Hôpitaux de Paris (AP-HP)-Université Paris Diderot - Paris 7 ( UPD7 ), Sociétés, Acteurs, Gouvernement en Europe ( SAGE ), Politique, Religion, Institutions et Sociétés : Mutations Européennes - Groupe de Sociologie Politique Européenne ( PRISME-GSPE ), Centre National de la Recherche Scientifique ( CNRS ), Centre de Transfusion Sanguine Aquitaine-Limousin ( CTS AQUITAINE-LIMOUSIN ), Géographie de l'environnement ( GEODE ), Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse - Jean Jaurès ( UT2J ), Université Pierre et Marie Curie - Paris 6 - UFR de Médecine Pierre et Marie Curie ( UPMC ), Université Pierre et Marie Curie - Paris 6 ( UPMC ), Agrosystèmes tropicaux ( ASTRO ), Institut National de la Recherche Agronomique ( INRA ), Hospices Civils de Lyon ( HCL ), IFR Saint-Louis, institut d'hématologie ( ISLIH ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Assistance publique - Hôpitaux de Paris (AP-HP)-Université Paris Diderot - Paris 7 ( UPD7 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Erasmus MC University medical Centre / Daniel den Hoed Cancer centre, Centre Hospitalier Régional Universitaire [Lille] ( CHRU Lille ), Centre hospitalier universitaire de Nantes ( CHU Nantes ), Laboratoire de Mathématiques et Modélisation d'Evry, PRES Université Nantes Angers Le Mans (UNAM)-Université de Lyon-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Strasbourg (UNISTRA), Centre National de la Recherche Scientifique (CNRS)-ENSIIE-Université d'Évry-Val-d'Essonne (UEVE)-Institut National de la Recherche Agronomique (INRA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Universitaire d'Hématologie (IUH), Université Paris Diderot - Paris 7 (UPD7)-Université Paris Diderot - Paris 7 (UPD7), Université Paris Diderot - Paris 7 (UPD7)-Assistance publique - Hôpitaux de Paris (AP-HP) (APHP), and Université Paris Diderot - Paris 7 (UPD7)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)

Subjects
0301 basic medicine, Male, medicine.medical_treatment, [SDV]Life Sciences [q-bio], Medizin, Graft vs Host Disease, Hematopoietic stem cell transplantation, Biochemistry, Linkage Disequilibrium, immune system diseases, HLA Antigens, Cytotoxic T cell, Child, ComputingMilieux_MISCELLANEOUS, HLA-DQB1, biology, Histocompatibility Testing, Incidence, Hematopoietic Stem Cell Transplantation, Hematology, Middle Aged, Allografts, 3. Good health, surgical procedures, operative, NK Cell Lectin-Like Receptor Subfamily K, Child, Preschool, Acute Disease, [SDV.IMM]Life Sciences [q-bio]/Immunology, Female, Adult, Adolescent, Immunology, Human leukocyte antigen, 03 medical and health sciences, MHC class I, medicine, Journal Article, Humans, Aged, Retrospective Studies, Transplantation, [ SDV ] Life Sciences [q-bio], Histocompatibility Antigens Class I, Infant, Newborn, Infant, Cell Biology, medicine.disease, Histocompatibility, stomatognathic diseases, 030104 developmental biology, Graft-versus-host disease, Chronic Disease, biology.protein
Abstract

Graft-versus-host disease (GVHD) is among the most challenging complications in unrelated donor hematopoietic cell transplantation (HCT). The highly polymorphic MHC class I chain-related gene A, MICA, encodes a stress-induced glycoprotein expressed primarily on epithelia. MICA interacts with the invariant activating receptor NKG2D, expressed by cytotoxic lymphocytes, and is located in the MHC, next to HLA-B. Hence, MICA has the requisite attributes of a bona fide transplantation antigen. Using high-resolution sequence-based genotyping of MICA, we retrospectively analyzed the clinical effect of MICA mismatches in a multicenter cohort of 922 unrelated donor HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 10/10 allele-matched HCT pairs. Among the 922 pairs, 113 (12.3%) were mismatched in MICA. MICA mismatches were significantly associated with an increased incidence of grade III-IV acute GVHD (hazard ratio [HR], 1.83; 95% confidence interval [CI], 1.50-2.23; P < .001), chronic GVHD (HR, 1.50; 95% CI, 1.45-1.55; P < .001), and nonelapse mortality (HR, 1.35; 95% CI, 1.24-1.46; P < .001). The increased risk for GVHD was mirrored by a lower risk for relapse (HR, 0.50; 95% CI, 0.43-0.59; P < .001), indicating a possible graft-versus-leukemia effect. In conclusion, when possible, selecting a MICA-matched donor significantly influences key clinical outcomes of HCT in which a marked reduction of GVHD is paramount. The tight linkage disequilibrium between MICA and HLA-B renders identifying a MICA-matched donor readily feasible in clinical practice.

Published
2016

3. Increased flexibility and liposome-binding capacity of CD1e at endosomal pH

Author

Sylvie Tourne, Natalia Bushmarina, Gaëlle Giacometti, Daniel Hanau, Luis F. Garcia-Alles, François Signorino-Gelo, and Jean-Pierre Cazenave

Subjects
0303 health sciences, Circular dichroism, Liposome, Endosome, Cell Biology, Golgi apparatus, Phosphate, Biochemistry, law.invention, 03 medical and health sciences, chemistry.chemical_compound, symbols.namesake, 0302 clinical medicine, Membrane protein, chemistry, law, 030220 oncology & carcinogenesis, symbols, Recombinant DNA, Protein precursor, Molecular Biology, 030304 developmental biology
Abstract

The plasma membrane proteins CD1a, CD1b and CD1c are expressed by human dendritic cells, the professional antigen-presenting cells of the immune system, and present lipid antigens to T lymphocytes. CD1e belongs to the same family of molecules, but accumulates as a membrane-associated form in the Golgi compartments of immature dendritic cells and as a soluble cleaved form in the lysosomes of mature dendritic cells. In lysosomes, the N-terminal propeptide of CD1e is also cleaved, but the functional consequences of this step are unknown. Here, we investigated how the pH changes encountered during transport to lysosomes affect the structure of CD1e and its ligand-binding properties. Circular dichroism studies demonstrated that the secondary and tertiary structures of recombinant CD1e were barely altered by pH changes. Nevertheless, at acidic pH, guanidium chloride-induced unfolding of CD1e molecules required lower concentrations of denaturing agent. The nonfunctional L194P allelic variant was found to be structurally less stable at acidic pH than the functional forms, providing an explanation for the lack of its detection in lysosomes. The number of water-exposed hydrophobic patches that bind 8-anilinonaphthalene-1-sulfonate was higher in acidic conditions, especially for the L194P variant. CD1e molecules interacted with lipid surfaces enriched in anionic lipids, such as bis(monoacylglycero)phosphate, a late endosomal/lysosomal lipid, especially at acidic pH, or when the propeptide was present. Altogether, these data indicate that, in the late endosomes/lysosomes of DCs, the acid pH promotes the binding of lipid antigens to CD1e through increased hydrophobic and ionic interactions.

Published
2011

4. Crystal structure of human CD1e reveals a groove suited for lipid-exchange processes

Author

Martine Gilleron, Gaëlle Giacometti, Gennaro De Libero, Lucia Mori, Daniel Hanau, Albert J. R. Heck, Cees Versluis, Diane de Paepe, Jacques Prandi, Julie Guiard, Germain Puzo, Laurent Maveyraud, Luis F. Garcia-Alles, Samuel Tranier, Lionel Mourey, Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées

Subjects
Models, Molecular, MESH: Antigens, CD1, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, Endosome, [SDV]Life Sciences [q-bio], Acylation, CD1, MESH: Protein Structure, Secondary, Plasma protein binding, Biology, Crystallography, X-Ray, Ligands, Protein Structure, Secondary, law.invention, Antigens, CD1, 03 medical and health sciences, MESH: Protein Structure, Tertiary, 0302 clinical medicine, Glycolipid, Antigen, law, MESH: Ligands, MESH: Protein Binding, Humans, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, 030304 developmental biology, MESH: Lipid Metabolism, 0303 health sciences, MESH: Acylation, Multidisciplinary, MESH: Humans, [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology, Lipid metabolism, Biological Sciences, MESH: Crystallography, X-Ray, Lipid Metabolism, MESH: Lipids, Lipids, In vitro, Protein Structure, Tertiary, Biochemistry, Recombinant DNA, Biophysics, MESH: Models, Molecular, 030215 immunology, Protein Binding
Abstract

International audience; CD1e is the only human CD1 protein existing in soluble form in the late endosomes of dendritic cells, where it facilitates the processing of glycolipid antigens that are ultimately recognized by CD1b-restricted T cells. The precise function of CD1e remains undefined, thus impeding efforts to predict the participation of this protein in the presentation of other antigens. To gain insight into its function, we determined the crystal structure of recombi-nant CD1e expressed in human cells at 2.90-Å resolution. The structure revealed a groove less intricate than in other CD1 proteins, with a significantly wider portal characterized by a 2 Å-larger spacing between the α1 and α2 helices. No electron density corresponding to endogenous ligands was detected within the groove, despite the presence of ligands unequivocally established by native mass spec-trometry in recombinant CD1e. Our structural data indicate that the water-exposed CD1e groove could ensure the establishment of loose contacts with lipids. In agreement with this possibility, lipid association and dissociation processes were found to be considerably faster with CD1e than with CD1b. Moreover, CD1e was found to mediate in vitro the transfer of lipids to CD1b and the displacement of lipids from stable CD1b-antigen complexes. Altogether, these data support that CD1e could have evolved to mediate lipid-exchange/editing processes with CD1b and point to a pathway whereby the repertoire of lipid antigens presented by human den-dritic cells might be expanded.

Published
2011
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5. Matching of MHC Class I Chain-Related Genes a and B Is Associated with Reduced Incidence of Severe Acute Graft-Versus-Host Disease after Unrelated Hematopoietic Stem Cell Transplantation

Author

Myriam Labopin, Nicole Raus, Régis Peffault de Latour, Mohamad Mohty, Katharina Fleischhauer, Gérard Socié, Daniel Hanau, Nicolas Jung, Ibrahim Yakoub-Agha, Xavier Lafarge, Miriam Hoffmann, Raphael Carapito, Jordi Sierra, Philippe Moreau, Anne Cesbron, Masao Ota, Seiamak Bahram, Arnon Nagler, A. Parissiadis, Mauricette Michallet, Ryad Tamouza, Franz Claas, Gaëlle Giacometti, Myriam Labalette, Ronnie van der Holt, Pascale Loiseau, Fabio Ciceri, Didier Blaise, Eric Spierings, Meiggie Untrau, Valérie Dubois, Catherine Paillard, Luca Vago, Noel Milpied, Antoine Toubert, Hidetoshi Inoko, Sergio Querol, Christophe Picard, Angélique Pichot, Dominique Charron, Sandra Michel, Katia Gagne, Bruno Lioure, Machteld Oudshoorn, Carapito, R, Jung, N, Untrau, M, Michel, S, Pichot, A, Giacometti, G, Cesbron, A, Gagne, K, Oudshoorn, M, Van der Holt, R, Labalette, M, Spierings, E, Picard, C, Loiseau, P, Tamouza, R, Toubert, A, Hanau, D, Parissiadis, A, Dubois, V, Raus, N, Lafarge, X, Vago, L, Ciceri, F, Paillard, C, Querol, S, Sierra, J, Fleischhauer, K, Nagler, A, Hoffmann, M, Milpied, N, Michallet, M, Lioure, B, de Latour, Rp, Labopin, M, Inoko, H, Claas, F, Blaise, D, Yakoub-Agha, I, Moreau, P, Charron, D, Ota, M, Mohty, M, Socie, G, Bahram, S, Immuno-Rhumatologie Moléculaire, Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Strasbourg (UNISTRA), and Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)

Subjects
medicine.medical_treatment, Immunology, Medizin, Hematopoietic stem cell transplantation, Human leukocyte antigen, Biochemistry, 03 medical and health sciences, 0302 clinical medicine, medicine, Minor histocompatibility antigen, Cumulative incidence, 030304 developmental biology, 0303 health sciences, Univariate analysis, business.industry, Donor selection, Cell Biology, Hematology, 3. Good health, Transplantation, surgical procedures, operative, [SDV.IMM]Life Sciences [q-bio]/Immunology, business, CD8, 030215 immunology
Abstract

Background: Graft-versus-host disease (GVHD) is a major cause of mortality after unrelated hematopoietic stem cell transplantations (HSCT). Despite the development of modern immunosuppressive strategies, a nearly perfectly controlled compatibility of the classical HLA genes (HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1) and availability of numerous so-called minor histocompatibility antigens (e.g. HY or HA-1), its incidence remains largely unexplained to date. MIC genes (MHC class I chain-related) - a distinct lineage of MHC class I genes – are promising candidates to explain, at least partially, the incidence of GVHD in HLA-matched transplantations. MICA and MICB are highly polymorphic (100 alleles for MICA and 40 for MICB) and encode functional cell-surface glycoproteins up-regulated by cell stress. They interact with NKG2D, an activating receptor expressed on the surface of cytotoxic αβ CD8+ and γδ T lymphocytes and natural killer cells. MIC genes are already known to have a HLA-independent effect on solid graft outcomes and may play a similar role in HSCT by triggering GVHD. Objective: The objective of the present study was to determine the impact of donor/patient matching at the MICA and MICB loci on the incidence of GVHD in patients undergoing unrelated HSCT. Methods: We retrospectively analyzed a multicenter cohort of 1072 unrelated transplantations performed between 1996 and 2013. All donor-recipient pairs were fully typed at high resolution for HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1 and were matched for ten of ten HLA alleles (HLA 10/10 matched). High resolution genotyping of MICA and MICB was performed by sequenced-based typing in order to define matching grades between donors and patients. The endpoints of the study were acute and chronic GVHD. Apart from HLA-DPB1 matching, statistical models were adjusted for major clinical variables which have been shown to be associated with outcome (patient’s age, patient’s and donor’s sex, patient’s and donor’s serological status for cytomegalovirus, year of transplantation, time to transplantation, transplantation center, source of stem cells, conditioning regimen, GVHD prophylaxis, treatment with anti-thymocyte globulin, disease category and severity at transplantation). Results: Of the 1072 transplantations, 134 (12.5 %) and 380 (35.4 %) were mismatched at the MICA and MICB locus, respectively. Both MICA and MICB mismatches were significantly associated with an increased incidence of severe acute GVHD (grades III-IV) in univariate and multivariate models (multivariate model: HR = 2.32, 95 % CI = 1.84-2.92; p=0.0003 for MICA and HR = 1.49, 95 % CI = 1.24-1.79; p=0.03 for MICB). At day 100 post-HSCT severe acute GVHD incidences in mismatched vs. matched transplantations were 19.62 % vs. 15.08 % and 20.00 % vs. 14.84 % for MICA and MICB, respectively (Figure 1). Chronic GVHD was associated with MICA and MICB mismatches in univariate analysis (HR = 1.55, 95 % CI = 1.27-1.89; p=0.029 for MICA and HR=1.38, 95 % CI = 1.19-1.62; p=0.03 for MICB), but showed only a trend for association in multivariate models. Figure 1 Estimated cumulative incidence curves of grades III–IV acute GVHD according to MICA (panel A) and MICB (panel B) matching status. The solid and dashed lines represent MIC matched and mismatched grafts, respectively. The Fine and Gray model was used with relapse and death considered as competing risks. Figure 1. Estimated cumulative incidence curves of grades III–IV acute GVHD according to MICA (panel A) and MICB (panel B) matching status. The solid and dashed lines represent MIC matched and mismatched grafts, respectively. The Fine and Gray model was used with relapse and death considered as competing risks. Conclusion: To date this is the largest reported MICA and MICB sequence analysis whether in HSCT or solid organ transplantation. Inclusion of MICA and MICB typing in the donor selection process may be a practical clinical strategy for lowering the risks of severe acute GVHD after unrelated HSCT. Disclosures No relevant conflicts of interest to declare.

Published
2014

6. Deciphering the Role of CD1e Protein in Mycobacterial Phosphatidyl- myo -inositol Mannosides (PIM) Processing for Presentation by CD1b to T Lymphocytes

Author

Emilie Layre, Diane Cala-De Paepe, Luis F. Garcia-Alles, Lucia Mori, Germain Puzo, Gaëlle Giacometti, Daniel Hanau, Martine Gilleron, Gennaro De Libero, Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Experimental Immunology, University Hospital Basel [Basel], Biologie des Cellules Dendritiques Humaines, and EFS-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Institut National de la Santé et de la Recherche Médicale (INSERM)

Subjects
MESH: Antigens, CD1, MESH: Mycobacterium tuberculosis, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, T-Lymphocytes, [SDV]Life Sciences [q-bio], Antigen presentation, CD1, Biology, Major histocompatibility complex, Biochemistry, Cell Line, Antigens, CD1, 03 medical and health sciences, 0302 clinical medicine, Antigen, alpha-Mannosidase, hemic and lymphatic diseases, Humans, MESH: Glycolipids, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Molecular Biology, Pan-T antigens, 030304 developmental biology, 0303 health sciences, Antigen Presentation, Antigens, Bacterial, MESH: Humans, Antigen processing, technology, industry, and agriculture, [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology, Cell Biology, Mycobacterium tuberculosis, Lipids, MESH: Cell Line, MESH: alpha-Mannosidase, carbohydrates (lipids), MESH: T-Lymphocytes, Immunoediting, MESH: Antigen Presentation, biology.protein, lipids (amino acids, peptides, and proteins), Glycolipids, Plant lipid transfer proteins, MESH: Antigens, Bacterial, 030215 immunology
Abstract

International audience; Lipids are important antigens that induce T cell-mediated specific immune responses. They are presented to T lymphocytes by a specific class of MHC-I like proteins, termed CD1. The majority of the described CD1-presented mycobacterial antigens are presented by the CD1b isoform. We previously demonstrated that the stimulation of CD1b-restricted T cells by the hexamannosylated phosphatidyl-myo-inositol (PIM(6)), a family of mycobacterial antigens, requires a prior partial digestion of the antigen oligomannoside moiety by α-mannosidase and that CD1e is an accessory protein absolutely required for the generation of the lipid immunogenic form. Here, we show that CD1e behaves as a lipid transfer protein influencing lipid immunoediting and membrane transfer of PIM lipids. CD1e selectively assists the α-mannosidase-dependent digestion of PIM(6) species according to their degree of acylation. Moreover, CD1e transfers only diacylated PIM from donor to acceptor liposomes and also from membranes to CD1b. This study provides new insight into the molecular mechanisms by which CD1e contributes to lipid immunoediting and CD1-restricted presentation to T cells.

Published
2012

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