Attempt at simplification of the rosette -- inhibition test for routine use in patients under immunosuppressive therapy.

Three hundred thirty three specimens of diluted sera from 69 patients under immunosuppressive therapy were tested for their ability to inhibit rosetting of normal human lymphocytes with SRBC. Statistical analysis of the results of the rosette-inhibition test have shown that there is a relationship of second degree between the inhibition index value and the dilution of serum. This relationship allowed to establish a formula for calculation of the theoretical titer (TT) from one arbitrally chosen dilution of serum. The results of empirical verification of the method are highly satisfactory. The theoretical and empirical titers of 23 tested sera were statistically identical. The proposed method shortens sixfold the time of testing.