The comparison of different rosette assay systems for the determination of T-lymphocytes in patients with solid malignant tumors.

The number of T-lymphocytes in the peripheral blood of 51 patients with different type of solid malignancies, 33 normal controls and 10 patients with rheumatoid arthritis was determined using different variations of the sheep red blood cell (SRBC) rosetting-technique (test temperature of 4 or 29 degrees C, medium substituted with or without fetal calf serum [FCS], SRBC treated or untreated with neuraminidase). No significant differences between cancer patients and normal controls were observed in the percentages of T-lymphocytes with the 4 degrees C incubation under any of the conditions tested. In absolute counts, however, a significantly decreased number of T-cells was observed in cancer patients, most likely due to the observed significant lymphopenia in this group. When the test temperature was raised to 29 degrees C, a significantly lower rosette formation was obtained in both percentages and absolute counts of peripheral T-cells in the group of cancer patients as compared to normal individuals only when both neuraminidase treated SRBC and FCS substituted medium were used. The question of whether the observed differences in the percentages and absolute counts of peripheral T-lymphocytes between cancer patients and normal controls using this rosette assay are due to a loss of a T-cell subpopulation or to an alteration in the metabolic state of T-cells in cancer patients remains open.