Sequential analysis of erythrocyte aggregation in health and diseases.

Aggregation of erythrocytes requires prolonged interaction of cellular and plasma constituents similar to in vivo conditions. To achieve this and then to analyse this process in various clinical and laboratory conditions, a PC-AT based system is developed. The erythrocyte suspension at 5% hematocrit in plasma is placed in a glass chamber, and the changes in laser transmitted intensity due to movement of the aggregates and erythrocytes in the path of the beam are sequentially recorded. From these data, aggregate size index, aggregate sedimentation time index, time required for completion of process and total number of fluctuations are calculated. From these, two additional parameters - effective number of cells and effective sedimentation duration - are calculated. The results show that in leprosy the aggregation of erythrocytes is reduced. In in vitro studies due to the cholesterol-enrichment of the erythrocyte membrane and treatment with pentoxifylline the aggregation of cells is increased whereas in disprin treated cells this is reduced compared to that of normal erythrocytes.