Studies in Trypanosomiasis. I. The Plasma Proteins and Sedimentation Rates of Erythrocytes of Rats Infected with Pathogenic Trypanosomes

Abstract

An accelerated sedimentation rate of the red blood cells has been observed in various pathological conditions. Newham and Martin (1928) have reviewed the literature on the various pathological conditions in which the sedimentation rate of the red blood cells is accelerated. It can be stated generally that increased sedimentation rate of the red blood cells has been observed in acute infections of all types, in anemia, and in conditions associated with extensive destruction of tissue. For these reasons, therefore, increased sedimentation rate, as a rule, is not diagnostic of any disease, although it can be taken as a corroborative evidence of certain types of disease. The factors responsible for the increased sedimentation rate of the red blood cells and the mechanism of the process involved are as yet not fully understood. Most investigators, however, have reported varying degrees of correlation between increased rate of red blood cell sedimentation and increased globulin and fibrinogen content of the plasma. In particular, Fahreus (1929), in his classical investigations of the phenomenon of rapid sedimentation, has surveyed the literature on the subject of the protein proportions of the blood in rapidly sedimenting cases and has stated that the survey revealed that fibrinogen or serum globulin or both were increased in those conditions when it was known or suspected that the settling velocity of the red blood cells was increased. In the course of studies in experimental trypanosomiasis it became necessary to study the levels of plasma proteins, since the results of investigations with formolgel, mercuric chloride, aldehyde and several other tests proposed for the diagnosis of trypanosomiasis, indicated clearly that there was a marked disturbance in the serum protein fractions during the course of infection. Furthermore, the sedimentation rate during the course of infection with pathogenic trypanosomes was studied in an attempt to determine whether a change in the serum protein was responsible for the increased sedimentation rate observed in these infections. Sice, Boisseau, Provost and Deniel (1931) and Sice and Bonnet (1936) studying the relationship of the serum albumin to serum globulin observed that the ratio serum albumin globulin was always less in human cases of trypanosomiasis than in normal globulin persons. The lowering of the quotient was due to the increased serum globulin. Newham and Martin (1928) found very little change in the levels of plasma proteins in a case of human trypanosomiasis in which treatment with tryparsamide had.