Investigation of attenuation levels of theileria annulata in cell culture passages with molecular markers

Objective: This study was carried out to detect the differences in expression levels in target genes using T. annulata-specific attenuation markers in low, medium and high passage strains of T. annulata infected cell culture. Materials and Methods: In this study, low, medium and high passages of Acarlar and Cincin isolates of T. annulata, medium and high passages of Ankara/Pendik isolate of T. annulata and vaccine strain, TeylovacTM, were used as parasite material. Initially, RNA was extracted from each related isolate, and cDNAs were synthesized of each extracted RNA sample. Then, the expression levels of each gene at different stages of passage were investigated by RT-PCR using attenuation markers. Results: As a result, the expression levels of HDAC, ADAM-19, MMP9 and TIMP-3 gene regions were measured and no significant increase or decrease in gene expression levels were determined among isolates with different passages. Conclusion: In this study, it was determined that genes used as attenuation markers were not differencially expressed in all isolates. Additionally, no positive and/or negative correlation was found between the expression levels of related genes among different passages of T. annulata cell lines. Keywords: Atenuation, cell culture, marker, Theileria annulata, vaccine