Cytokine profiles of dendritic cells (DCs) during infection with bovine leukaemia virus (BLV)

Abstract

BLV is an agent of enzootic bovine leukaemia (EBL), an infectious disease affecting cattle worldwide. BLV infection has been associated with immune system disorders and discrepancies in the cytokine network. The significance of dendritic cells in the pathogenesis of BLV infection is largely unknown, but considering their fundamental role in immune response it may be crucial. DCs precursors were isolated with the use of immunomagnetic beads from BLV-infected and BLV-free cows. From these precursors cultures of monocyte derived dendritic cells (MoDCs) were generated with the use of a cytokine cocktail (IL-4 and GM-CSF). Additionally, parallel DCs from BLV-negative animals were infected in vitro. The level of cytokines: IL-6, IL-10, IL-12(p40), IL-12(p70) was determined in DC cultures: infected in vitro, originating from naturally infected cattle and BLV-free cattle. The investigation showed significant changes in almost all analyzed populations of BLV-infected DCs. Cytokine profiles of blood MoDCs indicated activation of these groups during infection. In the case of spleen MoDCs and lymph node MoDCs a decrease in production of IL-12(p40) and IL-12(p70) in favour of IL-6 and IL-10 was noted, suggesting promotion of BLV infection development.

The Global Epidemiology of Bovine Leukemia Virus: Current Trends and Future Implications

“…The transcription level of IL-12 (p40) mRNA is significantly increased in the PBMC of AL cattle, while it is significantly decreased in PL cattle [198]. Furthermore, BLV infection activates the MoDc group, leading to a reduction in the expression levels of both IL-12 (p40) and IL-12 (p70) genes, which promotes the process of BLV infection [199,200]. BLV infection may also upregulate the expression of immunosuppressive molecules such as PD-L1, LAG-3, Tim-3, and CTLA-4 on the surface of PBMC through an unknown mechanism [201][202][203][204].…”

“…IL-10 possesses immunosuppressive properties and can inhibit the transcription of Tax and pol genes during BLV replication in PBMC. Furthermore, it has been observed that the secretion of IL-10 increases with the progression of BLV infection [199].…”

Application of Flow Cytometry in the Diagnosis of Bovine Epidemic Disease

“…Iwan et al [ 20 ] evaluated the effect of BLV infection on DC characteristics by taking bovine peripheral blood to isolate individual nucleated cells and isolating bone marrow dendritic cells (MDCs) from the individual nucleated cells, which were finally analysed using flow cytometry. The results showed that the level of IL-10 was significantly increased compared to the negative control group.…”