title: Herpesvirus saimiri-transformed CD8+ T cells as a tool to study Chediak-Higashi syndrome cytolytic lymphocytes.
abstract: Cytolytic CD8+ T lymphocytes are the main cell type involved in the fatal lymphoproliferative-accelerated phase of the Chediak-Higashi syndrome (CHS). To generate a cellular tool to study the defects of this T cell subset in vitro, we have used Herpesvirus saimiri, a lymphotropic virus that transforms human T lymphocytes into extended growth and in addition, endows them with natural killer (NK) features. Transformed CHS CD8+ T cells were generated and characterized in comparison with healthy controls. The results showed that transformed CHS T cells maintained the defects described in primary CHS lymphocytes, such as giant secretory lysosomes and impaired NK and T cell receptor/CD3-induced, perforin-mediated cytolytic activity [which, however, could be restored after extended culture in the presence of interleukin-2 (IL-2)]. Upon activation with phorbol ester plus calcium ionophore or upon extended culture with IL-2, transformed CHS T cells showed normal, perforin-independent plasma membrane CD178/CD95L/FasL-mediated cytolytic activity but negligible secretion of microvesicle-bound CD95L. Transformed (and primary) CHS T cells were otherwise normal for cytolysis-independent activation functions, such as proliferation, surface expression of several activation markers including major histocompatibility complex class II, and cytokine or surface activation-marker induction. Therefore, the CHS protein [CHS1/LYST (for lysosomal traffic regulator)] can be dispensable for certain NK and T cell cytolytic activities of activated CHS CD8+ T lymphocytes, but it seems to be required for microvesicle secretion of CD95L. We conclude that transformed CHS T cells may be useful as a tool to study in vitro the relative role of CHS1/LYST in NK and T lymphocyte cytolysis and antigen presentation.
authors.affiliation: Immunología, Facultad de Medicina, Universidad Complutense, 28040 Madrid, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Martín-Fernández
authors.forename: Juan A
authors.initials: JA
authors.lastname: Cabanillas
authors.forename: Miguel
authors.initials: M
authors.lastname: Rivero-Carmena
authors.forename: Esther
authors.initials: E
authors.lastname: Lacasa
authors.forename: Julián
authors.initials: J
authors.lastname: Pardo
authors.forename: Alberto
authors.initials: A
authors.lastname: Anel
authors.forename: Pedro R
authors.initials: PR
authors.lastname: Ramírez-Duque
authors.forename: Fernando
authors.initials: F
authors.lastname: Merino
authors.forename: Carlos
authors.initials: C
authors.lastname: Rodríguez-Gallego
authors.forename: José R
authors.initials: JR
authors.lastname: Regueiro
mesh_terms: D017951:Antigen Presentation; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology / Q000821:virology; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D002472:Cell Transformation, Viral; D002609:Chediak-Higashi Syndrome / Q000276:immunology* / Q000473:pathology / Q000821:virology; D053222:Fas Ligand Protein; D005260:Female; D005802:Genes, MHC Class II / Q000276:immunology; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D015759:Ionomycin / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D008247:Lysosomes / Q000187:drug effects / Q000276:immunology; D008562:Membrane Glycoproteins / Q000276:immunology; D011506:Proteins / Q000276:immunology*; D018139:Simplexvirus; D033921:Vesicular Transport Proteins
chemical_list: C505661:FASLG protein, human; D053222:Fas Ligand Protein; D007376:Interleukin-2; C102161:LYST protein, human; D008562:Membrane Glycoproteins; D011506:Proteins; D033921:Vesicular Transport Proteins; D015759:Ionomycin