Badania nad zakażeniem monocytÓw/makrofagÓw przez wirus białaczki bydła

The study was undertaken to determine whether monocytes or monocyte-derived macrophages (M/M) of serologically positive cattle were actively infected by Bovine Leukemia Virus (BLV). The M/ M were isolated from the blood of twelve cattle infected with BLV and two which were non-infected. Proviral DNA was detected by nested PCR in peripheral blood mononuclear cells from all the infected cattle, however, it was also present in eight M/M samples. Active virus replication in M/M, identified by syncytia formation assay, was noted in the M/M isolated from seven animals. Additionally, the presence of both proviral DNA and syncytia formation was significantly associated with persistent infections (PL form) in the examined cattle. Single-strand conformational polymorphism (SSCP) analysis was employed order to elucidate the role of M/M in the development of genetic variants of BLV. M/M and PBMC - derived proviral variants differed in the env region of BLV in DNA samples isolated from two of the animals. These findings indicate that BLV may be actively replicated in the monocytes/macrophages of naturally infected cattle and implies that these cells may develop different genetic varia ntions.