Exploration of the lysis mechanisms of leukaemic blasts by chimaeric T-cells.
Adoptive transfer of specific cytotoxic T lymphocytes (CTL) and Cytokine Induced Killer Cells (CIK) following genetic engineering of T-cell receptor zeta hold promising perspective in immunotherapy. In the present work we focused on the mechanisms of anti-tumor action of effectors transduced with an anti-CD19 chimaeric receptor in the context of B-lineage acute lymphoblastic leukemia (B-ALL). Primary B-ALL blasts were efficiently killed by both z-CD19 CTL and z-CD19 CIK effectors. The use of death receptor mediated apoptosis of target cells was excluded since agonists molecules of Fas and TRAIL-receptors failed to induce cell death. Perforin/granzyme pathway was found to be the mechanism of chimaeric effectors mediated killing. Indeed, cytolytic effector molecules perforin as well as granzymes were highly expressed by CTL and CIK. CD19 specific stimulation of transduced effectors was associated with degranulation as attested by CD107 membrane expression and high IFN-gamma and TNF-alpha release. Moreover inhibitors of the perforin-based cytotoxic pathway, Ca(2+)-chelating agent EGTA and Concanamycin A, almost completely abrogated B-ALL blast killing. In conclusion we show that the cytolysis response of z-CD19 chimaeric effectors is predominantly mediated via perforin/granzyme pathway and is independent of death receptors signaling in primary B-ALL.
Laurin
David
D
Etablissement Français du Sang, 38701 La Tronche, France. david.laurin@efs.sante.fr
Marin
Virna
V
Biagi
Ettore
E
Pizzitola
Irene
I
Agostoni
Valentina
V
Gallot
Géraldine
G
Vié
Henri
H
Jacob
Marie Christine
MC
Chaperot
Laurence
L
Aspord
Caroline
C
Plumas
Joël
J
D018941:Antigens, CD19 / Q000378:metabolism; D017209:Apoptosis; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D055612:Cytokine-Induced Killer Cells / Q000378:metabolism*; D005434:Flow Cytometry; D053804:Granzymes / Q000378:metabolism; D006801:Humans; D016219:Immunotherapy, Adoptive / Q000379:methods*; D051907:Lysosomal Membrane Proteins / Q000378:metabolism; D054353:Perforin / Q000378:metabolism; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000628:therapy*; D053218:Receptors, Death Domain / Q000378:metabolism; D015398:Signal Transduction; D013602:T-Lymphocytes, Cytotoxic / Q000378:metabolism*
D018941:Antigens, CD19; D051907:Lysosomal Membrane Proteins; D053218:Receptors, Death Domain; D054353:Perforin; D053804:Granzymes