Vol. 10, Special Issue 10 (2021)

Author(s):
Rajesh Singathia, Ravindra Sharma and Satish Kumar Batra

Abstract:
F-1 and LaSota strains of New castle disease were propagated in the laboratory using embryonated hen eggs via the allantoic cavity route. One group of thirty chicks were infected with F-1 strain and the other with LaSota strain with virus via oral and ocular route. Sequential lymphocyte from blood samples at days 0, 3,7,14, 21, and 28 post infection were collected and cell mediated immune response against F-1 and LaSota strains of New castle disease virus (NDV) at different days post inoculation was analyzed by performing lymphocyte proliferation assays and by fluorescence-activated cell sorting analysis of phenotypic markers of T lymphocytes. In both the group of chicks immunized with F-1 and LaSota strains of NDV, lymphocyte proliferation responses at different days post infection were significantly higher (P<0.05) compared to that of the control group on in vitro stimulation with antigen. On in vitro stimulation with Concanavalin A the mean stimulation index values in the group of birds immunized with F-1 or with LaSota strain of NDV were found to be significantly higher than that of control at most of the days. A statistically lower (P<0.05) proportion of CD₄⁺ T lymphocyte was observed on days 3 & 7 post infection in group of chickens inoculated with either F-1 or LaSota strain of NDV as compared to that of control birds. A lower proportion of CD₈⁺ T cells were observed on days 7 & 14 post infection in birds inoculated with either F-1 or with LaSota strain of NDV. The Cellular immune response is generated in the form of first suppression (day 3) followed by an increase in CD₄⁺ T lymphocytes and CD₈⁺ T lymphocytes.