93 http://www.ecevr.org/ CLINICAL EXPERIMENTAL VACCINE RESEARCH Review article Introduction Toxoplasmosis is a cosmopolitan zoonotic disease, caused by an intracellular protozo- an belonging to the Apicomplexa phylum that has a worldwide distribution [1-3]. Over one third of the human population are chronically infected worldwide [4-6]. Cats are the only definitive hosts, and several warm-blooded mammals, including humans, ro- dents, birds, etc. serve as intermediate hosts [3,7-9]. Additionally, Toxoplasma gondii was reported in snakes. Nasiri et al. (2016) [10] in Iran showed that 80.88% (55/68) of the examined snakes were positive by GRA6 gene and sequencing revealed over 98% similarity with T. gondii available sequences in GenBank [10]. A wide range of risk factors are involved in the prevalence of toxoplasmosis, so that they can affect the global/regional epidemiological figure of infection including: close contact with cats or keeping them indoors as pet animals, occupation, place of residence, education level, age, eating raw meat, gender, exposure to soil, the host immune re- sponse, etc. [4,5,11-13]. In humans, toxoplasmosis is often asymptomatic in immuno- competent persons, although in immunocompromised subjects such as patients with malignancies, human immunodeficiency virus‒positive individuals, and organ trans- © Korean Vaccine Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Com- mercial License (http://creativecommons.org/licenses/ by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, pro- vided the original work is properly cited. KOREAN VACCIN E SOCIETY Clin Exp Vaccine Res 2018;7:93-103 https://doi.org/10.7774/cevr.2018.7.2.93 pISSN 2287-3651 • eISSN 2287-366X Masoud Foroutan*, Leila Zaki*, Fatemeh Ghaffarifar Department of Parasitology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Received: March 28, 2018 Revised: June 18, 2018 Accepted: July 6, 2018 Corresponding author: Fatemeh Ghaffarifar Department of Parasitology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, P.O. Box 14115-111, Iran Tel: +98-21-82884553 Fax: +98-21-82884555 E-mail: ghafarif@modares.ac.ir *These authors contributed equally to this work. No potential conflict of interest relevant to this article was reported. The authors would like to thank all staff of Department of Parasitology of Tarbiat Modares University, Iran. Toxoplasmosis is a cosmopolitan zoonotic disease, which infect several warm-blooded mam- mals. More than one-third of the human population are seropositive worldwide. Due to the high seroprevalence of Toxoplasma gondii infection worldwide, the resulting clinical, mental, and economical complications, as well as incapability of current drugs in the elimination of parasites within tissue cysts, the development of a vaccine against T. gondii would be criti- cal. In the past decades, valuable advances have been achieved in order to identification of vaccine candidates against T. gondii infection. Microneme proteins (MICs) secreted by the micronemes play a critical role in the initial stages of host cell invasion by parasites. In this review, we have summarized the recent progress for MIC-based vaccines development, such as DNA vaccines, recombinant protein vaccines, vaccines based on live-attenuated vectors, and prime-boost strategy in different mouse models. In conclusion, the use of live-attenuated vectors as vehicles to deliver and express the target gene and prime-boost regimens showed excellent outcomes in the development of vaccines against toxoplasmosis, which need more attention in the future studies. Keywords: Toxoplasma gondii , Vaccines, Microneme, Immune responses, Adjuvant Recent progress in microneme- based vaccines development against Toxoplasma gondii