[Activation of neutrophil function by MDP-Lys(L 18)]

The study was carried out to confirm the effect of MDP-Lys (L 18) on the neutrophil number and function in the patients with lung cancer. The patients were enrolled only in case of leukopenia (equal or less than 3,000/mm3 after anticancer chemotherapy) and subcutaneously given 200 mcg of MDP-Lys (L 18) for 7 days. Mean leukocyte counts were found to be 3,900/mm3 and 5,500/mm3 one day and one week after MDP-Lys (L 18) treatment, respectively. The rate of "markedly effective" and "effective" was 53% (8/15). Chemiluminescence by zymosan showed a significant increase after MDP-Lys (L 18) treatment. However, no change of neutrophil function was observed in the tests of chemiluminescence by phorbol myristate acetate, superoxide (O2-) production, hydrogen peroxide (H2O2) production, chemotaxis, bacterial killing and opsonization. Transient fever was observed in 6 cases and eruption accompanied with one fever case. It was concluded that MDP-Lys (L 18) could prevent infection in cancer-bearing immunocompromised patients by increasing the neutrophil number and function.