Division of Parasitology, Central Drug Research Institute, Chattar Manzil Palace, M.G. Road, Lucknow, UP, India.
Exp Parasitol. 2012 Jul;131(3):377-82. doi: 10.1016/j.exppara.2012.05.007. Epub 2012 May 22.
Existing drugs for visceral leishmaniasis (VL) are partially effective, toxic, having high cost and long term treatment. Their efficacies are also compromised due to suppression of immune function associated during the course of infection. Combination therapy including a potential and safe immunostimulant with lower doses of effective drug has proven as a significant approach which is more effective than immunotherapy or drug therapy alone. In the present study, we have used the combination of Pam3Cys (an in-built immunoadjuvant and TLR2 ligand) and miltefosine. Initially dose optimization of both the agents was carried out and after that, antileishmanial effect of their combination was evaluated. All experiments were done in BALB/c mouse model. The immunomodulatory role of Pam3Cys on the immune functions of the host receiving combination treatment was also determined using immunological and biochemical parameters viz. phagocytosis, Th1/Th2 cytokines and production of ROS, RNS and H(2)O(2). Combination group showed significant enhancement in parasitic inhibition as compared to groups receiving miltefosine and Pam3Cys separately. Enhanced production of Th1 cytokines as well as ROS, RNS and H(2)O(2) was witnessed during the study of immunological alterations. Remarkable increase in phagocytosis index was also observed. Thus, the risk of development of drug resistance against miltefosine can be resolved through using low doses of it and Pam3Cys (single-dose) in combination and also provide a promising alternative for cure of leishmaniasis, with a pronounced transformation of the host immune response.
现有的内脏利什曼病(VL)药物部分有效,但具有毒性、成本高且治疗时间长。由于在感染过程中抑制了免疫功能,它们的疗效也受到了影响。联合治疗包括一种潜在的、安全的免疫刺激剂和低剂量的有效药物,已被证明是一种比单独免疫疗法或药物疗法更有效的方法。在本研究中,我们使用了 Pam3Cys(一种内置的免疫佐剂和 TLR2 配体)和米替福新的组合。最初对两种药物进行了剂量优化,然后评估了它们组合的抗利什曼原虫作用。所有实验均在 BALB/c 小鼠模型中进行。还使用免疫和生化参数(如吞噬作用、Th1/Th2 细胞因子以及 ROS、RNS 和 H2O2 的产生)来确定 Pam3Cys 对接受联合治疗的宿主免疫功能的免疫调节作用。与单独接受米替福新和 Pam3Cys 治疗的组相比,联合组显示出对寄生虫抑制的显著增强。在免疫变化的研究中,观察到 Th1 细胞因子以及 ROS、RNS 和 H2O2 的产生显著增加。吞噬指数也显著增加。因此,通过使用低剂量的米替福新和 Pam3Cys(单剂量)联合使用,可以解决米替福新耐药性发展的风险,并为治疗利什曼病提供有前途的替代方法,同时宿主免疫反应发生明显转变。