THE DYNAMICS OF ANTIGEN SPECIFIC PROLIFERATIVE RESPONSES OF LYMPHOCYTES AT EARLY STAGES OF BOVINE PARATUBERCULOSIS INFECTION

Abstract

The present study was aimed to quantify the dynamics of early antigen specific proliferative responses of lymphocytes to (protein) antigens associated with experimental Mycobacterium avium subsp. paratuberculosis (Mp) infection cattle. The data were collected from 20 experimentally infected calves, and 10 uninfected control animals, during the first 2 years of their lives. Several purified protein derivative antigens (Ppdp, Ppda, and Ppdb), two recombinant Mp heatshock proteins (Hsp65 and Hsp70) and whole bacteria (sonicated Mp strain 316F) were used to measure lymphocyte proliferation in a lymphocyte proliferation assay. Data were analyzed using a linear mixed effect (LME) model. The results showed significant group and timed effects for all antigens tested. At several time points, the responses in the infected group were found significantly higher as compared to control group. The Ppd antigens induced similar lymphocyte proliferation patterns, as compared to whole bacteria antigen and Hsp70. These results indicated that the antigen specific proliferative responses of lymphocytes differs for different antigens, probably related to differences in their availability during different stages of infection. The application of LME model is a useful tool for analyzing the quantitative longitudinal datasets. Keywords: dynamics, Mp, antigen, LME