Oxytetracycline/BSA is an antigen-adjuvant conjugate of Oxytetracycline and bovine serum albumin (BSA). The conjugation of the antigen with a protein adjuvant enhances the production of antigen-specific antibodies in vaccine models. This conjugate does not disrupt protein folding or affect major epitopes, and it also boosts cross-presentation and the generation of antigen-specific T cells.