- Last Update On : 2013-03-09
Immunosuppressive agents such as cyclosporine and steroids have long been used to prevent or treat episodes of allograft rejection. OKT3 is a monoclonal antibody, which is specifically directed against the T cells responsible for graft rejection. Blood samples from patients receiving OKT3 therapy demonstrate an almost complete lack of T lymphocytes expressing the CD3 surface marker. Determining the absolute number of CD3 positive cells in peripheral blood samples helps to monitor the efficacy of OKT3 treatment.
The panel is designed to enumerate T cell subsets before and during episodes of transplant rejection and OKT3 therapy. Initially all T cell CD2, CD3, CD4, and CD8 subsets are virtually eliminated. As treatment progresses, CD2, CD4 and CD8 positive cells gradually reappear, while the CD3 population remains depressed. Optimal OKT3 dosages reduce CD3 positive cell counts to less than 10 cells per microliter throughout the 10 to 14 day course of treatment.
Specimen requirement is one 10 mL green top (sodium heparin) or yellow top (ACD) tube. Samples should remain at room temperature.