Mouse antibody‐coated lymphocytes during OKT3 therapy in liver transplantation

Flow cytometry has been a technique in search of a use in transplantation. With each new monoclonal antibody, it has been hoped that the secrets of rejection would be unlocked. The usefulness of CD3 + T‐ lymphocyte counts to predict successful treatment of organ transplant rejection has been called into question. CD2 + , CD3 + , and mouse antibody‐coated CD3 lymphocytes were followed by flow cytometry in 44 liver transplant patients during OKT3 therapy for induction or rejection. CD3 + lymphocyte counts did not predict successful management of rejection by OKT3. When expressed as percentages of the total lymphocyte count, an increasing trend in CD2+ and mouse antibody‐coated CD3 + lymphocytes after day 7 of OKT3 therapy portended persistent or recurrent rejection within 2 months of treatment. It is uncertain if the increasing population of mouse antibody‐coated CD3 cells is due to an immune phenomen or decreased clearance by an ailing liver. Care should be taken when using CD3 lymphocyte counts as indicators of adequate OKT3 therapy in liver transplantation.