Immune cell function testing: an adjunct to therapeutic drug monitoring in transplant patient management.
Each year, 55 000 organ transplants are performed worldwide. Cumulatively, the number of living organ recipients is now estimated to be over 300 000. Most of these transplant recipients will remain on immunosuppressive drugs for the remainder of their lives to prevent rejection episodes. Controlled doses of these drugs are required to prevent over-medication, which may leave the patient susceptible to opportunistic infection and drug toxicity effects, or under-dosing, which may lead to shortened graft survival because of rejection episodes. This paper describes the result of a multicenter study conducted at the Universities of Pittsburgh, Alabama and Maryland to evaluate an in vitro assay (CylexTM Immune Cell Function Assay) for the measurement of global immune response in transplant patients receiving immunosuppressive therapy. The assay uses a whole blood sample to maintain the presence of the drug during incubation. Following overnight incubation of blood with phytohemagglutinin (PHA), CD4 cells are selected using paramagnetic particles coated with a monoclonal antibody to the CD4 epitope. The CD4-positive cells are targeted as major immunosuppressive drugs are designed to specifically inhibit T-cell activation which has been implicated in rejection. The data generated at these three sites were submitted in support of an Food and Drug Association (FDA) application for the use of this assay in the detection of cell-mediated immunity in an immunosuppressed population. The assay was cleared by the FDA on April 2, 2002. This cross-sectional study was designed to establish ranges for reactivity of this bioassay in the assessment of functional immunity for an individual solid organ recipient at any point in time.
Kowalski
Richard
R
Cylex Incorporated 8980-I, Columbia, MD 21045, USA. rkowalski@cylex.net
Post
Diane
D
Schneider
Mary C
MC
Britz
Judith
J
Thomas
Judy
J
Deierhoi
Mark
M
Lobashevsky
Andrew
A
Redfield
Robert
R
Schweitzer
Eugene
E
Heredia
Alonso
A
Reardon
Elise
E
Davis
Charles
C
Bentlejewski
Carol
C
Fung
John
J
Shapiro
Ron
R
Zeevi
Adriana
A
D000328:Adult; D018791:CD4 Lymphocyte Count; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D016572:Cyclosporine / Q000097:blood; D016903:Drug Monitoring; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007111:Immunity, Cellular; D007118:Immunoassay / Q000379:methods*; D007166:Immunosuppressive Agents / Q000097:blood; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects; D016559:Tacrolimus / Q000097:blood; D014181:Transplantation Immunology
D007166:Immunosuppressive Agents; D010835:Phytohemagglutinins; D016572:Cyclosporine; D016559:Tacrolimus