This study was attempted to know the effects of systemic cytotoxic drugs, known to suppress the bone marrow cells, on epidermal Langerhans cells (LC) and to examine the possible role of the bone marrow in the maintenance of the epidermal LC population...
This study was attempted to know the effects of systemic cytotoxic drugs, known to suppress the bone marrow cells, on epidermal Langerhans cells (LC) and to examine the possible role of the bone marrow in the maintenance of the epidermal LC population in guinea pigs. Intraperitoneal injection of cyclophos phamide (Cy) and methotrexate (MTX) were done eigher at once (300 mg/kg/day for Cy and 350 mg/kg for MTX) or consecutively for 10 days (30 mg/kg/day for Cy and 35 mg/kg/day for MTX). Total white blood cell (TWBC) count and epidermal LC count utilizing ATPase staining were done before and following administration of the cytotoxic drugs.
The results were as follows:
1. Statistically significant LC reduction was observed in Cy-administered groups.
2. The decrease and then increase in LC numbers followed the tone marrow suppression and then recovery.
3. The degree of LC reduction and subsequent recovery correlated to the degree of the bone marrow suppression.
4. More than 15-25 days were required for the injured epidermis to regain normal LC number in Cy-administered groups.
Above results presents evidence of the effects of the systemic cytotoxic drugs on epidermal LC-ATPase in guinea pigs and support the idea that LC are being replenished from the bone marrow following epidermal injury. Further studies are requred to know whether the LC recovery in numbers is due only to LC migrating from the bone marrow following the injury or also includes local recovery of LC injured, but not totally lost.