Evaluation of cytomegalovirus (CMV)-specific T cell immune reconstitution revealed that baseline antiviral immunity, prophylaxis, or preemptive therapy but not antithymocyte globulin treatment contribute to CMV-specific T cell reconstitution in kidney transplant recipients.
BACKGROUND
The ultimate goal of organ transplantation is the reestablishment of organ function and the restoration of a solid immunity to prevent the assault of potentially deadly pathogens. T cell immunity is crucial in controlling cytomegalovirus (CMV) infection. It is still unknown how preexisting antiviral T cell levels, prophylaxis, or preemptive antiviral strategies and pharmacological conditioning affect immune reconstitution.


METHODS
Seventy preemptively treated CMV-seropositive recipients, 13 prophylaxis-treated CMV-seronegative recipients of seropositive donor transplants, 2 seropositive recipients of seronegative donor kidneys, and 27 pretransplant subjects were enrolled in a cross-sectional study and analyzed for CMV viremia (DNAemia) and CMV-specific T cell response (interferon-gamma enzyme-linked immunospot assay) before transplantation and at 30, 60, 90, 180, and 360 days after transplantation.


RESULTS
CMV-seropositive transplant recipients displayed a progressive but heterogeneous pattern of immune reconstitution starting from day 60 after transplantation. CMV-seronegative recipients did not mount a detectable T cell response throughout the prophylaxis regimen. A single episode of CMV viremia (CMV copy number, 7000-170,000 copies/mL) was sufficient to prime a protective T cell immune response in CMV-seronegative recipients. Antithymocyte globulin treatment did not significantly affect CMV-specific T cell response.


CONCLUSIONS
Baseline immunity, antiviral therapy but not antithymocyte globulin treatments profoundly influence T cell reconstitution in kidney transplant recipients.
Abate
Davide
D
Departments of Histology, Microbiology, and Medical Biotechnology, Padua General Hospital, University of Padua School of Medicine via Gabelli, Padova, Italy. davide.abate@unipd.it
Saldan
Alda
A
Fiscon
Marta
M
Cofano
Simona
S
Paciolla
Adriana
A
Furian
Lucrezia
L
Ekser
Burcin
B
Biasolo
Maria Angela
MA
Cusinato
Riccardo
R
Mengoli
Carlo
C
Bonfante
Luciana
L
Rossi
Barbara
B
Rigotti
Paolo
P
Sgarabotto
Dino
D
Barzon
Luisa
L
Palù
Giorgio
G
D000328:Adult; D000368:Aged; D000961:Antilymphocyte Serum / Q000627:therapeutic use*; D000998:Antiviral Agents / Q000627:therapeutic use*; D018890:Chemoprevention / Q000379:methods*; D003430:Cross-Sectional Studies; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000276:immunology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology*; D014180:Transplantation; D014766:Viremia
D000961:Antilymphocyte Serum; D000998:Antiviral Agents; D007371:Interferon-gamma