Pancreas transplantation under alemtuzumab (Campath-1H) and tacrolimus: Correlation between low T-cell responses and infection.
BACKGROUND
Alemtuzumab induction and tacrolimus-based immunosuppression has been effective in pancreas transplantation. Despite the encouraging results of this minimalistic approach to immunosuppression, infection still remains a significant cause of morbidity. The Cylex ImmuKnow [corrected] assay was used in this study to compare pancreas recipient clinical states (stable, rejection, infection) with T cell responses.


METHODS
Blood samples were taken from pancreas recipients pretransplant and at approximately three-month intervals posttransplant for analysis of T cell responses. When possible, T cell responses were also quantified during changes in clinical status (infection or rejection).


RESULTS
A range between 100-300 ng/ml adenosine triphosphate (ATP) was found in stable patients (mean 194+/-123, n = 51) with good graft function and no infection or rejection. A low T cell response was highly correlated with infectious states. The fourteen patients with infections/posttransplant lymphoproliferative disease had a mean ATP of 48 ng/ml. Risk hazard analysis showed that patients with ATP levels <100 ng/ml were four to seven times more susceptible to infection compared to stable patients. Four patients with rejection showed a T cell response of 550 ng/ml ATP, which was statistically significant compared to stable patients, although the sampling numbers (9) were too small to be conclusive.


CONCLUSIONS
The Cylex ImmuKnow [corrected] assay is a valuable tool to more precisely modulate immunosuppression in pancreas transplant patients. In particular, the assay is extremely useful in detecting overly immunosuppressed patients vulnerable to infections.
Thai
Ngoc L
NL
Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA. thainl@upmc.edu
Blisard
Deanna
D
Tom
Kusum
K
Basu
Amit
A
Smetanka
Cindy
C
Tan
Henkie
H
Bentlejewski
Carol
C
Glidewell
Janice
J
Britz
Judy
J
Kowalski
Richard
R
Shapiro
Ron
R
Fung
John
J
Marcos
Amadeo
A
Zeevi
Adriana
A
D000255:Adenosine Triphosphate / Q000097:blood; D000074323:Alemtuzumab; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000912:Antibodies, Neoplasm / Q000008:administration & dosage*; D001681:Biological Assay; D006084:Graft Rejection / Q000175:diagnosis / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D007239:Infections / Q000175:diagnosis / Q000276:immunology; D015166:Monitoring, Immunologic / Q000379:methods*; D016035:Pancreas Transplantation / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D016559:Tacrolimus / Q000008:administration & dosage*
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000912:Antibodies, Neoplasm; D007166:Immunosuppressive Agents; D000074323:Alemtuzumab; D000255:Adenosine Triphosphate; D016559:Tacrolimus