• β-glucan;
  • L. major;
  • suppression;
  • lesion

Summary The potential of β-glucan (glucan) to suppress the progression of lesions caused by virulent strains of Leishmania major in genetically susceptible BALB/c mice when administered post challenge was evaluated. Glucan particles (glucanp) prepared from Saccharomyces cerevisiae were injected i.v. at 7-day intervals starlins 7 days after parasite challenge. Four injections gave a more rapid and a higher extent of suppression than 1, 2 or 3 injections. Mice receiving only parasites, a glucose solution, starch particles or glucanp by the i.p. route showed a progressive increase in footpad thickness and developed ulcerating lesions. An alkali solubilized glucan (glucanas) was injected (50 μg, 200 μg and 400 μg/mousc) 4 times at 4 day intervals either i.v. or i.p. starling four days post parasite challenge. Glucanas injection by either route blocked lesion development; the 50 μg treatment had already substantial effects and 400 μg in the i.p. route prevented even the initial stages of lesion formation. Touch prints from the lesion area and from the liver of mice receiving 200 μg glucanas were amasiigote free. The anti Leishmania antibody litre of glucanas treated mice was lower and their sera recognized fewer antigens than that of control Leishmania bearing mice.