title: Immunotherapeutic effects of chitin in comparison with chitosan against Leishmania major infection.
abstract: Chitin and chitosan microparticles (MPs) are important immune system stimulators. The aim of this study was to evaluate the protective effects of these compounds in comparison with each other against Leishmania infection in BALB/c mice infected with Leishmania major (L. major). Female BALB/c mice were injected subcutaneously with 2×10(5) promastigotes. Chitin and/or chitosan MPs (<40 μm) were subcutaneously injected in the BALB/c mice with two-day intervals until two weeks. Mice in all groups were sacrificed at 12 weeks post-infection. Enumeration of viable parasites was performed using limiting dilution assay. Furthermore, the animals (5 mice/group) were sacrificed two weeks post-infection. The lymph node cells were isolated and the effects of the chitinous MPs on the proliferation and production of cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) were determined. The mean sizes of lesions were significantly smaller in chitin (0.6±0.12 mm) and chitosan treated groups (1.2±0.8 mm) than in the control group (6.2±1.7 mm) (P<0.05). The parasite load in the lymph nodes of the treated mice was significantly lower than that in the lymph nodes of controls (1.31×10(6) vs 8.24×10(7) parasite/lymph node [P=0.032] and 7.49×10(6) vs 8.24×10(7) parasite/lymph node [P=0.05] for chitin and chitosan MPs treatment, respectively). We found that chitinous MPs induced cell proliferation and that chitin but not chitosan increased TNF-α and IL-10 production. Chitin appears that it has more effect than chitosan against leishmaniasis. The current study revealed that chitinous MPs had significant activity against L. major and could be considered as new therapeutic modality in leishmaniasis.
authors.affiliation: Department of Immunology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Applied Cell Sciences, School of Advance Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: m.mollahoseini@sbmu.ac.ir.
authors.forename: Mostafa Haji Molla
authors.initials: MH
authors.lastname: Hoseini
authors.affiliation: Department of Immunology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Moradi
authors.affiliation: Department of Immunology, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Alimohammadian
authors.affiliation: Department of Immunology, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Vahid Khaze
authors.initials: VK
authors.lastname: Shahgoli
authors.affiliation: Department of Immunology, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Hayedeh
authors.initials: H
authors.lastname: Darabi
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Rostami
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D049109:Cell Proliferation; D002686:Chitin / Q000008:administration & dosage / Q000276:immunology*; D048271:Chitosan / Q000008:administration & dosage / Q000276:immunology*; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D005260:Female; D007167:Immunotherapy; D007371:Interferon-gamma / Q000096:biosynthesis; D018320:Leishmania major / Q000276:immunology / Q000502:physiology; D016773:Leishmaniasis, Cutaneous / Q000276:immunology* / Q000469:parasitology / Q000517:prevention & control / Q000628:therapy*; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D008807:Mice, Inbred BALB C; D059208:Parasite Load; D065566:Subcutaneous Absorption; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D000276:Adjuvants, Immunologic; D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D002686:Chitin; D007371:Interferon-gamma; D048271:Chitosan
keywords: Chitin; Chitosan; Immunotherapeutic effect; Leishmania major