|Title||The role of Vδ2-negative γδ T cells during cytomegalovirus reactivation in recipients of allogeneic stem cell transplantation.|
|Publication Type||Journal Article|
|Year of Publication||2010|
|Authors||Knight A, Madrigal AJ, Grace S, Sivakumaran J, Kottaridis P, Mackinnon S, Travers P, Lowdell MW|
|Date Published||2010 Sep 23|
|Keywords||Adolescent, Adult, Cell Proliferation, Child, Cytomegalovirus, Cytomegalovirus Infections, Female, Hematopoietic Stem Cell Transplantation, Humans, Male, Middle Aged, Receptors, Antigen, T-Cell, gamma-delta, T-Lymphocyte Subsets, Transplantation, Homologous, Virus Activation, Young Adult|
Reactivation of cytomegalovirus (CMV) remains a serious complication after allogeneic stem cell transplantation, but the role of γδ T cells is undefined. We have studied the immune reconstitution of Vδ2negative (Vδ2neg) γδ T cells, including Vδ1 and Vδ3 subsets and Vδ2positive (Vδ2pos) γδ T cells in 40 patients during the first 24 months after stem cell transplantation. Significant long-term expansions of Vδ2neg but not Vδ2pos γδ T cells were observed during CMV reactivation early after transplantation, suggesting direct involvement of γδ T cells in anti-CMV immune responses. Similarly, significantly higher numbers of Vδ2neg γδ T cells were detected in CMV-seropositive healthy persons compared with seronegative donors; the absolute numbers of Vδ2pos cells were not significantly different. The expansion of Vδ2neg γδ T cells appeared to be CMV-related because it was absent in CMV-negative/Epstein-Barr virus-positive patients. T-cell receptor-δ chain determining region 3 spectratyping of Vδ2neg γδ T cells in healthy subjects and patients showed restricted clonality. Polyclonal Vδ2neg cell lines generated from CMV-seropositive healthy donors and from a recipient of a graft from a CMV-positive donor lysed CMV-infected targets in all cases. Our study shows new evidence for role of γδ T cells in the immune response to CMV reactivation in transplantation recipients.