Immunostimulatory effects of polar glycopeptidolipids of Mycobacterium chelonae for inactivated rabies vaccine

Humoral and cellular immune responses were analyzed with Fuenzalida–Palacios rabies vaccine associated with pGPL-Mc, polar glycopeptidolipids extracted from Mycobacterium chelonae, aiming at its use as adjuvant. These results were compared to those obtained with BCG, a well-known immunostimulator, under the same conditions. Rabies vaccine plus pGPL-Mc (2.5 mg/kg) induced a significant increase in serum neutralizing activity, in vitro lymphocyte proliferation (spontaneous, specific and mitogen stimulation) and delayed type hypersensibility. In addition, pGPL-Mc, as well as BCG, enhanced the vaccine potency. Our results support further studies to encourage the use of pGPL-Mc as an immunostimulator of veterinary vaccines, before consideration for human vaccines.