Background: Chitin micro-particles have the ability to modulate immune responses. In order to investigate the immunoadjuvant potential of chitin, the parasite burden in Balb/c mice infected with Leishmania Major under treatment with chitin microparticles was evaluated. In measuring the parasitic load, titration method, which is the most accurate assessment of the effectiveness of therapies and vaccine evaluation in experimental models of Leishmania infection was used.
Methods: Balb/c mice were intradermally infected with 2 × 105 stationary phase of Leishmania Major promastigotes into their base of the tail and eight weeks later, parasite burden were measured and compared between test (6 mice/group) that recived 100 μg/ml microparticle subcutaneously at the base of the tail every two days and control groups (6 mice/group) that received PBS. The onset and size of ulcer among two groups were compared as well.
Results: Onset of ulcers in the treated mice compared to control showed a significant delay (p<0.02) and the lesion development in the micro-particle recipient mice were significantly smaller. Although the parasite load in treated mice was lower but statistically significant differences were not found between the test group and control (p<0.88).
Conclusion: The combined use of monitoring the size of the cutaneous lesions and the determination of the parasite burden will reflect more accurately the status of disease. Although the removal of the viseralized parasite was not found among chitin trated group, but onset and size of ulcer was impressed. Immunoadjuvant effects of chitin microparticles in Leishmania infection models requires further studies.
