Cytokines restore infectious bursal disease virus induced immunosuppression in in vitro assays

In the present investigation, we have examined the susceptibility of chicken peripheral blood mononuclear cells (PBMC) and blood monocytes to infectious bursal disease virus (IBDV) in an in vitro assay using IBDV specific monoclonal antibodies and FACS analysis. Virus exposed PBMC and monocyles were also subjected to mitogen-induced lymphoproliferative (LP) response using MTT assay and detemination of nitrite levels. Efforts have also heen made to analyse the immunoregulatory role of cytokincs, particularly, IL-2 and GM-CSF, using IBDV exposed PBMC and monocytes.

FACS analysis of IBDV exposed PBMC, and monocytcs showed expression of IBDV antigens on 15% and 6% cells. respectively. IBDV exposed PBMC and monocytes showed down regulation of mitogen (PHA) induced lymphoproliferativc response. Both the cytokines IL-2 and GM-CSF showed restoration of depressed LP responses but magnitude of restoration was higher in presence of GM-CSF.