Analysis of erythropoietin and erythropoietin receptor genes expression in cattle during acute infection with Trypanosoma congolense

Acute Trypanosoma congolense infection induced moderate, transient anemia in N'Dama cattle (trypanotolerant) and severe anemia in Boran cattle (trypanosusceptible). Erythropoietin receptor (EpoR) was cloned and sequenced from the two breeds of cattle. A single position mutation of Tyr in the Boran to His in the N'Dama predicted amino acid sequence was revealed, The mRNA transcription of erythropoietin (Epo) in kidneys and EpoR in the bone marrow of infected cattle was determined by competitive reverse transcription and the polymerase chain reaction (RT-PCR), Though Epo mRNA transcription increased in the kidneys during infection, the increase was not significantly different (p > 0.05) between the two breeds of infected cattle. The level of EpoR transcripts in the bone marrow of infected N'Damas was significantly higher (p < 0.05) than that detected in the marrows from infected Boran cattle. While infection seem to increase levels of transcription of IL-1 alpha and beta, and TNF alpha in kidneys from both Boran and N'Dama cattle, no significant difference was detected in the level of mRNAs of these cytokines in the kidney from the two breed of cattle. The amount of IFN gamma mRNA transcripts were not changed with infection in N'Dama cattle, while on the contrary a significant higher levels of IFN gamma was found in kidneys from infected Boran cattle as compared to the other groups, A significant (p < 0.05) increase in the levels of IL-1 alpha and beta, and IFN gamma mRNA transcripts were detected in the marrows of infected Borans as compared to the infected N'Dama cattle. In this study the increase in the level of TNF alpha mRNA in the marrows of the two infected breeds was not different. This implies there is no negative effect of TNF alpha on hematopoiesis during acute infection, These findings suggest that the levels of Epo and EpoR in the infected Boran cattle were inadequate for their degree of anemia, which might be due in part to high expression of IFN gamma during acute infection with T. congolense. (C) 1999 International Society for Experimental Hematology, Published by Elsevier Science Inc.