Role of L-lysine HCl in immunopotentiation towards development of suitable tuberculosis vaccination.

L-Lysine HCl is being proposed to be a possible biocompatible adjuvant to enhance immune response by virtue of its probable non-specific bridging action and cellular proliferation properties. This proposal has been tried to be substantiated by carrying out experimentation where L-lysine HCl has been used as an adjuvant (various groups based on mode of application and frequency of booster dose were designed) in tuberculosis vaccination experiments with heat killed Mycobacterium tuberculosis (MTB) and Bacille Calmette Guerin (BCG). Antibody titre has been followed in all the experiments as a measure of immune response. Amongst the various groups designed, group 1A (L-lysine HCl was given at a separate site as that of the antigen; lysine booster was given to this group intermittently, i.e. lysine given on 0th, 7th, 14th, 21st days of immunization) came out as the stand-alone leader. This mode and frequency of application was then compared with a group which received a standard adjuvant, viz. alhydrogel. Results were obtained which showed the following order in terms of decreasing antibody titre: alhydrogel group > lysine group > control group. Considering the biocompatible nature of lysine in comparison with the reportedly hazardous nature of alum adjuvants, we propose L-lysine HCl as a probable adjuvant in vaccination.