Contents lists available at ScienceDirect Acta Tropica journal homepage: www.elsevier.com/locate/actatropica Combined transcriptomics and proteomics to identify differential proteins involved in the immune response to the parasite schistosoma japonicum in snail hosts pre-infected with exorchis sp Peng Li a,b , Theerakamol Pengsakul d , Yunlong Li a,b , Tianyichen Xiao a,b , Zhiming Su a,b , Haixia Ren a,b , Wenfeng Peng a,c , Mingke Lu a,c , Tianwei Lin a,b, ⁎ , Shuaiqin Huang a,b,c, ⁎ a State Key laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, State-province Joint Engineering Laboratory of Targeted Drugs from Natural Products, School of Life Sciences, Xiamen University, Xiamen, Fujian, China b Cancer Research Center of Xiamen University, Xiamen, Fujian, P. R. China c Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China d Faculty of Medical Technology, Prince of Songkla University, Hat Yai, Songkhla, Thailand ARTICLE INFO Keywords: Oncomelania hupensis Transcriptome Proteome Exorchis sp Schistosoma japonicum ABSTRACT Oncomelania hupensis is the obligate intermediate host of Schistosoma japonicum, and it also serves as the first intermediate host for Exorchis sp., which uses Parasilurus asoyus as its definitive host rather than humans. In previous studies, Tang et al. found that all S. japonicum larvae can be blocked and killed in O. hupensis pre- infected with Exorchis sp. eggs. However, the molecular and cellular mechanisms involved in this process remain unclear. Therefore, in the present study, a combined transcriptomic and proteomic analysis was performed to identify the differential proteins involved in the immune response to the parasite S. japonicum in the O. hupensis snail host pre-infected with Exorchis sp. trematodes. The results showed that a total of 46,162 unigenes were obtained with 23,535 (50.98%) unigenes annotated in relevant databases, and 3811 proteins from O. hupensis were identified. In addition, iTRAQ-based quantitative proteomic analysis demonstrated that among three groups (OhSj-1_vs_OhN-1, OhE-1_vs_OhN-1 and OhES-1_vs_OhN-1), there were 146 common differential proteins including 44 up-regulated proteins and 90 down-regulated proteins, and 195 differential proteins exclusive to only one experimental group, including 91 up-regulated proteins and 104 down-regulated proteins, which were defined as the Common group and the Only group, respectively. KEGG analysis showed that 15 and 11 differential proteins were annotated in “Infectious diseases” in the Common group and the Only group, respectively, in- dicating that these proteins may be involved in the snail host immune response to parasite infection. These data will be helpful for better understanding the host-parasite interaction, and could pave the way towards exploring the mechanisms involved in the biological control on S. japonicum in O. hupensis. They also provide valuable information about developing new anti-schistosomiasis strategies. 1. Introduction Schistosomiasis, which is one of the world's most widespread human parasitic diseases, is caused by blood flukes of the genus Schistosoma, and more than 200 million people suffer from this devastating disease worldwide (Colley et al., 2014). In recent years, continuous integrated strategies of controlling schistosomiasis including health education, the improvement of water supplies and sanitation, selective population- chemotherapy, and control of the intermediate host have achieved a remarkable reduction in the prevalence of schistosomiasis infection and the burden of the disease among humans (WHO 2016 and 2017; McManus et al., 2018). However, there have been some negative im- pacts, including the emergence of praziquantel-resistant parasites be- cause of high rates of re-infection, environmental pollution and damage caused by the extensive use of chemical molluscicides (Mutapi et al., 2017; Xu et al., 2016; Wang et al., 2008). Consequently, developing alternative effective anti-schistosome strategies is crucial for preventing schistosomiasis transmission and eradicating the overwhelming burden of this parasitic disease. As the unique intermediate host of Schistosoma japonicum, the freshwater amphibious snail Oncomelania hupensis provides an ideal environment for its amplification and development (Ross et al., 2001). https://doi.org/10.1016/j.actatropica.2020.105623 Received 9 December 2019; Received in revised form 28 June 2020; Accepted 6 July 2020 ⁎ Corresponding authors. State Key Laboratory of Cellular Stress Biology, School of Life Science, Xiamen University, Xiamen, Fujian Province 361002, China E-mail addresses: twlin@xmu.edu.cn (T. Lin), huangshuaiqin@foxmail.com (S. Huang). Acta Tropica 211 (2020) 105623 Available online 06 July 2020 0001-706X/ © 2020 Elsevier B.V. All rights reserved. T