Hosseini-Vasoukolaei Nasibeh, Idali Farah, Khamesipour Ali, Yaghoobi-Ershadi Mohammad Reza, Kamhawi Shaden, Valenzuela Jesus G, Edalatkhah Haleh, Arandian Mohammad Hossein, Mirhendi Hossein, Emami Shaghayegh, Jafari Reza, Saeidi Zahra, Jeddi-Tehrani Mahmood, Akhavan Amir Ahmad
Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Department of Medical Entomology and Vector Control, Health Sciences Research Center, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran.
Parasit Vectors. 2016 Jun 24;9(1):357. doi: 10.1186/s13071-016-1633-z.
Sand fly saliva has been shown to help parasite establishment and to induce immune responses in vertebrate hosts. In the current study, we investigated the pattern of expression of two Phlebotomus papatasi salivary transcripts in specific physiological and seasonal conditions at a hyperendemic area of zoonotic cutaneous leishmaniasis (ZCL) in Iran.
Sand flies were collected during 2012-2013, and grouped according to physiological stages such as unfed, fed, semi-gravid, gravid, parous, nulliparous, infected or non-infected with Leishmania major and also based on the season in which they were collected. Quantitative Real-Time PCR was applied for assessment of the expression of two relevant salivary transcripts, PpSP15 and PpSP44, associated to protection from and exacerbation of ZCL, respectively.
The expression of PpSP15 and PpSP44 transcripts was significantly up-regulated (1.74 and 1.4 folds, respectively) in blood fed compared to unfed flies. Among four groups of fed, unfed, semi-gravid and gravid flies, the lowest levels of PpSP15 and PpSP44 expression were observed in gravid flies. Additionally, the expression levels of both PpSP15 and PpSP44 transcripts in P. papatasi collected during summer were significantly up-regulated (3.7 and 4.4 folds, respectively) compared to spring collections. In addition, the PpSP15 transcript exhibited a significant up-regulation (P < 0.05) in non-infected flies compared to those infected with L. major.
This study contributes to our knowledge of the differential expression of salivary genes among different groups within a P. papatasi population under natural field conditions. Cutaneous and visceral leishmaniasis are of public health importance in many parts of Iran and neighbouring countries where P. papatasi is the proven and dominant sand fly vector for ZCL, the most prevalent and endemic form of the disease in Iran. Therefore, the current study could be helpful in understanding the influence of salivary genes on Leishmania transmission by phlebotomine sand flies. Our findings demonstrate the differential expression of salivary transcripts under various physiological conditions potentially influencing the sand fly capacity for parasite transmission as well as the outcome of disease.
白蛉唾液已被证明有助于寄生虫的建立，并能在脊椎动物宿主中诱导免疫反应。在本研究中，我们调查了伊朗人兽共患皮肤利什曼病（ZCL）高度流行地区，两种巴氏白蛉唾液转录本在特定生理和季节条件下的表达模式。
在2012 - 2013年期间收集白蛉，并根据生理阶段（如未进食、已进食、半妊娠、妊娠、已产卵、未产卵、感染或未感染硕大利什曼原虫）以及收集白蛉的季节进行分组。应用定量实时PCR评估两种相关唾液转录本PpSP15和PpSP44的表达，它们分别与预防和加重ZCL有关。
与未进食的白蛉相比，已进食白蛉中PpSP15和PpSP44转录本的表达显著上调（分别为1.74倍和1.4倍）。在已进食、未进食、半妊娠和妊娠白蛉的四组中，妊娠白蛉中PpSP15和PpSP44的表达水平最低。此外，与春季收集的巴氏白蛉相比，夏季收集的巴氏白蛉中PpSP15和PpSP44转录本的表达水平均显著上调（分别为3.7倍和4.4倍）。此外，与感染硕大利什曼原虫的白蛉相比，未感染的白蛉中PpSP15转录本表现出显著上调（P < 0.05）。
本研究有助于我们了解在自然野外条件下巴氏白蛉种群中不同组之间唾液基因的差异表达。皮肤利什曼病和内脏利什曼病在伊朗的许多地区以及邻国具有公共卫生重要性，在这些地区，巴氏白蛉是已证实的ZCL主要白蛉传播媒介，而ZCL是伊朗最普遍和地方性的疾病形式。因此，本研究有助于理解唾液基因对白蛉传播利什曼原虫的影响。我们的研究结果表明，在各种生理条件下唾液转录本的差异表达可能会影响白蛉传播寄生虫的能力以及疾病的结局。
