Immune response in guinea pigs injected with insoluble beryllium compounds

The changes in immune response of guinea pigs intrapleurally injected once with beryllium oxide (BeO) or beryllium copper alloy (Be-Cu) were examined. To evaluate the changes in immune response of guinea pigs, two indicators, beryllium lymphocyte transformation test (Be-LTT) and complement nemolytic activity (CH₅₀), were used. The BeO or Be-Cu injection groups was divided three groups, a high concentration injection group (36 μg Be dose), a low concentration injection group (3.6 μg Be dose) and the control group. The Be-LTT and CH₅₀ were determined in the blood of guinea pigs at 4, 8 and 16 weeks after Be administration. The Be-LTT value at the 4th week in the BeO groups (a high or low concentration injection group, respectively) showed a statistically significant increase (p<0.01) compared with that of the control. In the Be-LTT value for BeO at 8 and 16 weeks after Be injection and the Be-Cu groups, there were no statistical difference between the Be administration groups and the control. On the other hand, only the CH₅₀ of the high concentration group at the 8th week in the BeO injection group was significantly decreased (p<0.01) compared with that of the control. In the other Be injection group, no significant changes in the CH₅₀ was observed compared with the control group. On the basis of the results observed in the present study, there may be a slight difference in the effect on the immune response of guinea pigs caused by BeO or Be-Cu administration. The immunotoxicity of Be in guinea pigs may manifest itself more intensely in the cellular immune response than in the humoral immune response.