Separation of relapsing fever spirochaetes from blood by DEAE cellulose anion exchanger

Abstract

LANHAM (1968) reported that several species of trypanosomes can be completely freed from host blood dements by passing infected blood through columns of DEAE or TEAE cellulose, under appropriate conditions of pH and ionic strength. Many infective organisms are less electronegative than blood elements (BROWN and BROOM, 1935), and this is the basis of the separation reported by Lanham. The behaviour of various trypanosome species during separation on DEAE cellulose columns is parallded by their behaviour during dectrophoresis (SZENT-GYORGYI, 1921; HOLLINGSHEAD, PETHICA and RILEY, 1963). SZENT-GYORGYI (1921) indicated that two Borrelia species (reported as Spirochaeta gallinarum and Recurrensspirochtiten) have an electronegative charge at pH 7 similar to those trypanosome species which can successfully be separated on DEAE cellulose columns; we have therefore applied column techniques to the separation of Borrelia spp. from the blood of laboratory animals. In this laboratory B. duttoni has previously been separated from blood by differential centrifugation (FULTON and SMITH 1960; GINGER 1964), but to avoid platdet contamination one must defibrinate by collecting blood in sodium citrate and then adding calcium chloride (FULTON and SPOONER, 1959). Some difficulty in applying these centrifugal techniques became apparent during the preparation of some antigenic variants of B. duttoni in a pure form for immunological studies, from infections in which few spirochaetes were present in the peripheral blood.