ORIGINAL ARTICLE Active components of mantis eggs and their immunomodulatory effect in a mouse model Ali Mohammad Zand 1 & Mojtaba Saadati 1 & Jamil Zargan 1 Received: 21 February 2018 /Accepted: 15 August 2018 # Institute of Zoology, Slovak Academy of Sciences 2018 Abstract Tenodera angustipennis is an Asian praying mantis, whose crude extracts have long been used for the prevention and treatment of bacterial and viral diseases. Despite significant progress in obtaining biomaterials from praying mantis, antiherpetic activity of T. angustipennis eggs is not well defined. In this study, we characterized the crude extracts from T. angustipennis eggs using high performance liquid chromatography (HPLC), gas chromatography (GC), and gas chromatography-mass spectrometry (GC/MS) methods. Inhibition of cell proliferation by mantis egg extracts and isolated components was investigated on lymphocytes in a MTT assay. Furthermore, the effects of egg extracts against the herpes simplex virus type 1 (HSV-1) strain KOS (HSV-1 KOS) were evaluated in a mouse model. The HPLC and GC/MS results showed that the extracts are mainly composed of stearic acid monoterpenes, octadecanoic acid, hexadecanoic acid, and propionic acid. Investigation on the immunomodulatory effects of the extracted components following infection of mice with HSV-1 KOS virus showed an increase in serum interferon-gamma level (26.01 ± 5.21 vs. 18.67 ± 3.23 pg/mL, respectively) and interleukin-10 level (106.64 ± 4.13 vs. 48.04 ± 3.12 pg/mL, respectively) in test and control groups (for both p < 0.05). It indicates that the mantis egg components have shifted the cytokines induction to the anti-inflammatory arm and probably truncated inflammation caused by HSV-1 KOS virus. Our findings can be considered as an early attempt to reveal the comprehensive biological properties of T. angustipennis eggs as new anti-inflammatory compo- nents in future pharmaceutical investigations. Keywords Tenodera angustipennis . Praying mantis . HSV-1 KOS . Interferon-gamma . Interleukin-10 . Immunomodulation Introduction Praying mantises are warm-adapted insects which are spread worldwide, with >2600 species in 15 families (Brannoch et al. 2017; Rose and Hurd 2016). Two Asian species, Tenodera aridifolia sinensis (Stoll, 1813) and Tenodera angustipennis (Saussure, 1869) are spread in the Mediterranean up to central Europe (Brannoch et al. 2017; Hornig et al. 2017). Recent publications have shown that extracts of T. angustipennis adults and their ootheca have fibrinolytic ac- tivity, and therefore could be exploited for the treatment of myocardial infarction and hemorrhoids (Carle et al. 2017). This effect can be attributed to the lysis of thrombin by mantis egg fibrolase (MEF) (Hahn et al. 2001; Walker et al. 2012). To date, three classes of MEF (MEF-1, -2, and - 3) have been identified which display fibrinolytic activity (Cho et al. 1999; Hahn et al. 2001). In addition, comparative analytical methods have shown that protease activity of the three classes is consid- erably different (Cho et al. 1999; Fujita et al. 1993; Linn and Griebeler 2016). Accordingly, the majority of fatty acid com- ponents in mantis egg crude extracts have inhibitory activity on virus replication, assembly of viral particles and their biological functions (Walker et al. 2012). Herpes simplex virus type 1 (HSV-1) is an ubiquitous path- ogen, responsible for neonatal malignancies, and causes disease in 8 to 60 cases per 100,000 live births in the USA (Matsura and Morooka 1983; Westley et al. 2011). Despite significant pro- gresses in clinical treatment strategies of oral HSV-1 infection, there are only a few approved drugs (Hooi et al. 2002; Westley et al. 2011). The keratitis, encephalitis, and infection-related blindness are the most serious complications of the oral HSV- 1 infection in adults and children (Huber 2003). The nature- * Ali Mohammad Zand kpazand@ihu.ac.ir; ali2007zand@yahoo.com 1 Department of Biology, Basic Science Faculty, IHU, Tehran, Iran Biologia https://doi.org/10.2478/s11756-018-0111-9