A Cryo-precipitating Factor

Abstract

Evidence was elicited from two cases suggesting the presence of a pathologic blood factor causing precipitation of normal blood-proteins upon cooling. In one case, cold intolerance, general deterioration, splenomegaly, anemia, an elevated blood sedimentation rate, and plasmacytosis in the marrow aspirate appeared after a myocardial infarction. A cryoprotein which was a coprecipitate of fibrinogen and gamma globulin and incorporated the coagulation factors was detected. In the second case, cold sensitivity developed insidiously in a man suffering from cystolithiasis. A cryoglobulin was detected. After precipitation of the cryoproteins, the supernatant fluids were decanted and normal blood constituents, including normal serum, oxalated and heparinized plasmas, fibrinogen or gamma globulin were added to samples from these supernatants. Reversible reprecipitation occured when these mixtures were chilled. In the first case reprecipitation occured in all samples but in the second case only when normal plasma and gamma globulin were added. These precipitates were found to be similar to the original precipitates. From the later series of experiments, much less precipitation could be educed from similarly treated supernatants than from those in the original set of experiments, suggesting the presence of an exhaustible factor responsible for these phenomena. The notion that the cryoproteins are normal plasma proteins which are cold precipitated by a pathologic blood factor is explored and comparisons are made to similar cases reported in the literature.