First record of a reptile trypanosome isolated from Glossina pallidipes in Kenya.

Trypanosomes, isolated from the gut of a naturally infected Glossina pallidipes in Kiboko, Kenya, were grown in vitro. The cultured trypanosomes ("F4"-stock) showed a wide variety in morphological stages, not characteristic of the salivarian trypanosomes that are known to occur in the Kiboko area. Identification of the "F4"-stock was attempted by isoenzyme studies, infection of tsetse flies and of experimental animals. Electrophoretic isoenzyme patterns of the "F4"-organisms were developed for ten soluble enzymes and compared with those of 5 reference stocks of salivarian trypanosomes and 2 stocks of Trypanosoma theileri. For the T. theileri comparisons six enzymes were used. It was found that the "F4"-trypanosome clearly differed from the 3 salivarian species and from T. theileri. Experimental infection of laboratory bred Glossina m. morsitans showed that the "F4"-organisms developed in the posterior station of the alimentary tract and the cultured trypanosomes were infective to non-indigenous reptiles. This is believed to be the first record of the isolation and the isoenzyme characterisation of a non-salivarian reptile trypanosome from a naturally infected tsetse fly of the morsitans group (subgenus Glossina) in a savannah area in Africa.

Preliminary investigations on isoenzyme variants of lymphoblastoid cell lines infected wih Theileria species.

The electrophoretic mobilities of seven enzymes from eight theileria-infected bovine lymphoblastoid cell lines originating in Kenya and Iran were compared. The isoenzyme patterns of phosphoglucomutase, malate dehydrogenase, malic enzyme and glucose-6-phosphate dehydrogenase were the same for all cell lines infected with any of the three Theileria species. Theileria annulata could be clearly differentiated from T parva and T lawrencei on the basis of three enzymes: glucose phosphate isomerase, glyceraldehyde phosphate dehydrogenase and aldolase. T parva and T lawrencei isoenzyme patterns were alike except for glucose phosphate isomerase, where two sets of isoenzyme mobility were shown which, however, did not separate the two species.

The electrophoretic mobilities and activities of eleven enzymes of bloodstream and culture forms of Trypanosoma brucei compared.

Eleven soluble enzymes in the supernatant of bloodstream Trypanosoma brucei were compared for electrophoretic mobility and activity with those of T. brucei cultures grown in 3 different media. All bands of each enzyme found in the bloodstream form were also present in the cultured material, but extra bands of malate dehydrogenase (MDH) (EC 1.1.1.37), aspartate aminotransferase (ASAT) (EC 2.6.1.1), and in 2 to 6 cultures of isocitrate dehydrogenase (ICD) (EC 1.1.1.42) were present in culture forms but not in bloodstream forms. An interfering enzyme, peculiar to cultured T. brucei, which reacted with 2-oxoglutarate and possibly a trace amount of ammonium ions, ran with the fast-moving ASAT bands. Threonine dehydrogenase activity, high in cultured trypanosomes irrespective of the medium used but low in bloodstream trypanosomes, was markedly lower in Trypanosoma evansi and a much passaged T. brucei 8/18. Glucosephosphate isomerase activity on the other hand was high in bloodstream and low in cultured trypanosomes. Glutamate dehydrogenase activity was too low to record reliably in bloodstream trypanosomes, but could be clearly detected in cultured forms. As the differences point to some changes in gene expression between the two forms, culture material is likely to replace trypanosomes from living animals for electrophoretic characterization only when considerable comparative work has been done.

Five trypanosomatid species of insects distinguished by isoenzymes.

Blastocrithidia culicis, Crithidia deanei, Crithidia fasciculata, Herpetomonas samuelpessoai, Leptomonas seymouri and Leishmania tarentolae grown in cultures were compared by electrophoretic mobility for isoenzymes in 6 enzymes. All species were found distinct in these characteristics. Endosymbiotic C. deanei, which was identical to the aposymbiotic C. deanei in 5 enzymes, had an extra band in aspartate aminotransferase. No differences in isoenzymes were found between members of one species maintained in 2 different culture media.

Isoenzyme patterns of cultured Trypanosoma cruzi: changes after prolonged subculture.

1. The isoenzyme patterns of four soluble enzymes in seven stocks of T. cruzi were determined by electrophoresis. According to their patterns they could be classified into four sets. 2. The isoenzyme patterns of two stocks were influenced by the number of subcultures. 3. Five stocks from man are distinct from those derived from a silvatic reservoir. 4. Since the isoenzyme patterns of a stock isolated from a patient with acute disease were similar to those of a silvatic reservoir, its recent introduction into the domiciliary cycle is postulated.

The influence of lorry transport on the Trypanosoma vivax infection rate in Nigerian trade cattle.

In Nigeria in 1974 and 1975 there was an apparent sharp reduction in the prevalence of trypanosomiasis of cattle at several markets and control points. Some of the decrease appears to be due to the tsetse eradication programmes and Sahelian drought, but the change to lory transport as the principal means of moving cattle from the northern grazing areas to the south-western markets, which replaced a trek of at least three weeks, was probably an important factor.

Enzyme electrophoresis in characterizing the causative organism of Gambian trypanosomiasis.

Trypanosoma (Trypanozoon) brucei includes three morphologically identical subspecies which are poorly defined by clinical behaviour; T. b. brucei does not infect man, whereas T. b. rhodesiense causes an acute, and T. b gambiense a chronic, disease. Thirty-three isolates of the complex, each of which had previously been identified on clinical or other criteria, were compared by the electrophoretic patterns of two trypanosomal enzymes, alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT). One particular ALAT pattern clearly segregated a group of human pathogens of which all except one were labelled T. b. gambiense. The exception was labelled T. b. rhodesiense, and in addition three putative T. b. gambiense isolates did not have this pattern; it is suggested that only one presents a serious anomaly. The T. b. gambiense group could also be subdivided by three ASAT patterns which coincided with known groupings based on serological criteria.

Isoenzymes of two aminotransferases among Trypanosoma vivax in Nigerian cattle.

During a period of three months, thin-layer starch-gel electrophoresis was used to examine the isoenzymes of alanine and asparate aminotransferases from samples of T. vivax collected from naturally infected Nigerian cattle. Experimentally infected cattle sheep and goats were also studied. Three patterns, termed Sets 1,2 and 3, differed in both enzymes. The stability of the enzyme patterns was generally confirmed in experimental animals. The results are discussed in relation to subspeciation in T. vivax.