Mouse monoclonal antibody against human CD3 antigen of T lymphocyte(Wuhan Institute of Biological Products Co., Ltd.)

To investigate the efficacy of the specific murine anti-human CD(3) T lymphocyte monoclonal antibody (CD(3) MoAb) for severe aplastic anemia (SAA).

13 SAA patients were chosen with a medium age of 22 years, including 4 untreated patients and 9 nonresponding to previous management. They were treated with 5 mg of CD(3) MoAb per day for a total 10 days.

The response rate was 11/13, including 2 cured and 2 remission cases during a follow up of 3 to 15 months. As compared with the pretreatment condition the proliferation of bone marrow in 8 cases become better; the leukocytes, granulocytes, hemoglobin and platelets of peripheral blood increased 1.59 x 10(9)/L, 0.72 x 10(9)/L, 40 g/L and 47 x 10(9)/L respectively (P < 0.01, respectively); the ratio of CD(4)/CD(8) of T cell subsets increased from 1.12 to 1.42 while the expression of HLA-DR antigen decreased from 29.2 to 15.2 (P < 0.01, respectively); TNF alpha, IFN gamma and IL-2 secreted by peripheral blood mononuclear cells (PBMNCs) decreased obviously from 267, 784 and 92 to 152, 570 and 51 U/ml on the average respectively (P < 0.01, respectively). The main side effects were fever in all the patients and shortness of breath in 4 cases, but none died during the therapy.

In contrast to other kinds of common immune suppressor, CD(3) MoAb showed better response and probably higher efficacy and safety for SAA. It is necessary to have more cases and to follow up longer to estimate its long term effect and side effects.