NK cells are lymphocytes who play a role in the control of viral infections , tumor and fœtal tolerance. They belong to innate immune cells but they have a link with adaptative immunity. Indeed, after some viral infections such as CMV, Chikungunya, B hepatitis etc, a subset of NKG2C+ NK cells expands and can transfer, in murine models, a " memory " that can better control CMV infections. CMV reactivation is a major cause of morbidity and mortality after allogeneic hematopoietic ste cell transplantation in humans. The aim of this prospective study is to evaluate the role of NK cells, in particular NKG2C+ NK cells in the control of CMV but also Adenovirus after allo HSCT. Peripheral NK cells from 30 and 10 patients who reactivated respectively CMV and AdV are prospectively studied (extensive phenotyping and functional studies before and after administration of anti viral drugs) and compared with 30 allotransplanted patients who didn't reactivate CMV in a pair analysis, and 30 healthy donors serologically + for CMV.
For both groups: 28ml of peripheral blood samples are collected at different points. Group 1 : before and after anti viral treatment . Control group 2: one point after allo-HSCT; Control group 3: 1 point before transplant. Phenotypical study of NK cells: activating and inhibitory receptors, activation and differentiation's markers. Phenotypical studies of the ligands on infected cells. Genotypic study of KIR receptors (Kirotype); functional studies: polyfunctionality essay (flow cytometry): degranulation CD107a, IFNg, TNFa production).
Study Type
OBSERVATIONAL
Enrollment
90
peripheral blood samples are collected
Hôpital Pitié Salpêtriere
Paris, France
RECRUITINGNk cells phenotype (activation, differentiation, memory NK cell) and function (cytoxicity and cytokines production) measured by flow cytometry
CD3-CD56+ NK cells will be analyzed by Flow cytometry with an appropriate monoclonal antibodies (mAb) cocktail: anti-CD3 ,CD56, CD16, CD159a/NKG2A , CD85J; HLA-DR ; CD62L , CD161; KIR2DL1 and KIR3DL1, and KIR2DL2/KIR2DL3. The state of NK cells differentiation and maturation will be assessed by the analyze of thoses phenotypic markers and will be compared with healthy donors.
Time frame: Change from "before antiviral treatment", " half treatment" (1 week or 2 week after the beginning of the treatment), 1 month "post treatment" and 3 month "post treatment"
NK cells cytoxicity and cytokines production when incubated with standard HLA class I negative K562 target cells
Polyfunctional assay will test the capacity of NK cells degranulation and production of cytokines when incubated with standard HLA class I negative K562 target cells in the presence of anti-CD107a ,IFN-g, or TNF-a mAb. The state of NK cells differentiation and maturation will be assessed by the analyze of thoses phenotypic and will be compared with healthy donors.
Time frame: Change from "before antiviral treatment", " half treatment" (1 week or 2 week after the beginning of the treatment), 1 month "post treatment" and 3 month "post treatment"
Effect of CMV and AdV infection compared with healthy donors
The state of NK cells differentiation and maturation will be assessed by the analyze of thoses phenotypic and functional markers and will be compared with healthy donors.
Time frame: Change from "before antiviral treatment", " half treatment" (1 week or 2 week after the beginning of the treatment), 1 month "post treatment" and 3 month "post treatment"
In vitro Nk cells ligands analyzes on infected cells by CMV
Monocyte are differentiated in macrophage cells and infected by the CMV strain TB40/E. Nk cell ligands will be analyzed on infected cells. NK cells from infected patients post allogenic transplantation will be tested against in vitro infected cells. Being a model in vitro, it is not possible to determine in advance which ligands will be identified.
Time frame: approximately 18 months after Study Completion Date (last participant's last visit)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.