Establishment of primary chicken embryo myoblast cell culture, antigenic epitopes prediction and production of anti activin receptor type IIB polyclonal antibody in chicken.

The detection of activin receptor typeIIB (ACTRIIB) protein, a prominent negative muscle growth regulator has paramount value in augmenting growth traits through molecular breeding schemes in chicken. The study was formulated to establish primary chicken embryo myoblast culture (CEM) using 9th and 18th day chick embryos and to develop antibodies for immunodetection of ACTRIIB protein. The physicochemical and structural attributes of the ACTRIIB sequence were evaluated to identify substantial antigenic regions. The ACTRIIB sequence was transfected into CEM and expressed protein was injected subcutaneously into rats to produce hyperimmune serum. The average propensity of protein sequence for beta turns, surface accessibility, chain flexibility, antigenicity, hydrophilicity and linear epitopes was 0.978, 1.000, 0.991, 1.038, 1.258 and 0.512, respectively. The 9th day CEM exhibited confluency (80-90%) earlier than the 18th day. The expression of myogenic regulatory factors in 9th day myoblasts was higher than the 18th day by 7.28, 5.16, 6.28 and 6.93 folds for MYF5, MRF4, MYOG and MYOD, respectively. The ACTRIIB mRNA was downregulated by 2.54 folds on the 9th day compared to the 18th day myoblasts and protein varied significantly between 9th and 18th day myoblasts. The CEM culture can be harnessed unequivocally to investigate molecular mechanisms underlying muscle growth besides raising antibodies.