Correlation between leukocyte-associated plasma proteins and white cell differential count

Prealbumin, albumin, orosomucoid (including the cellular variant orosomucoid2), alpha 1-antitrypsin, haptoglobin and transferrin were quantified in 107 cell samples from acute and chronic myeloid leukaemia, seven polycytaemia, seven normal blood marrow and 56 normal blood leukocytes by crossed immunoelectrophoresis. By statistical multivariate analyses, the individual plasma proteins and their combined protein patterns were correlated with the diagnoses and it was demonstrated that acute leukaemia cell samples contained significantly different protein patterns compared with the other diagnostic groups and normal controls. By comparison with the white blood cell differential count, in 78 samples of acute leukaemia, it was demonstrated that the protein patterns were significantly correlated with the specific cell types in the samples. In all, the differential counts accounted for about 29% of the variation in protein patterns. Alpha 1-antitrypsin was found significantly correlated with the myeloblasts and myelo-band cells. Orosomucoid2 and haptoglobin were significantly correlated with mature granulocytes and albumin was significantly correlated with lymphocytes. In some cell samples, after cytotoxic treatment of acute leukaemia, the granulocytes did not have orosomucoid2 despite normal morphology, suggesting defective maturation of these granulocytes. These results indicate that the mechanisms responsible for uptake of plasma proteins are highly specific for different cell types and in the case of myeloid cells specifically related to cell differentiation.