ABSTRACT
INTRODUCTION: Numerous mutations in the bovine tumour necrosis factor receptor type two (TNF-RII) gene have been identified, but their biological consequences remain poorly understood. The aim of this study was to determine whether polymorphism in the analysed loci of the bovine TNF-RII gene is linked with the size of cell subpopulations naturally infected with bovine leukaemia virus (BLV) which serve important immune functions in the host. MATERIAL AND METHODS: Samples originated from 78 cows. Polymorphisms in the studied gene were determined by PCR-RFLP and DNA sequencing by capillary electrophoresis. BLV infection was diagnosed by the immunofluorescence (IMF) technique and nested PCR. Cell subpopulations were immunophenotyped with IMF. RESULTS: Similar and non-significant differences in the average percentages of TNFα±, IgM+TNFα±, and CD11b+TNFα±cells infected with BLV were noted in individuals with various genotypes in the polymorphic sites g.-1646T > G and g. 16534T > C of the TNF-RII gene, and significant differences in the percentages of these subpopulations were observed between selected microsatellite genotypes (g.16512CA(n)). CONCLUSION: STR polymorphism and the number of CA dinucleotide repeats in intron 1 of the TNF-RII gene influence the frequency of TNF+, CD11b+TNF+, and IgM+TNF+ subpopulations naturally infected with BLV. Polymorphism in the gene's other two sites do not affect the size of these cell subpopulations.
ABSTRACT
In Black-and-White cattle, polymorphism of acid phosphatase (AcP) of blood leukocytes is determined by a pair of autosomal alleles. The aim of the study was to determine the relationship between AcP polymorphism and the metabolic efficiency of phagocytes in the first months after calving of cows naturally infected with the bovine leukaemia virus. The studied population consisted of 91 Black-and-White cows aged 3-6 years, from one herd. Enzootic bovine leukaemia (EBL) was diagnosed with the immuno-enzymatic ELISA method and a PCR molecular test. Additionally, agarose gel electrophoresis and the cytochemical method were used to determine the AcP polymorphism and activity in leukocytes. The metabolic activity of phagocytes was determined by the nitroblue tetrazolium (NBT) reduction test. Significant differences in metabolic efficiency of granulocytes were observed between cows representing different AcP phenotypes. No significant differences in levels of the analysed indices were observed between the EBL-positive and EBL-negative cows and between the three subsequent months after calving.