title: Decidual expression and localization of human surfactant protein SP-A and SP-D, and complement protein C1q.
abstract: Surfactant proteins SP-A and SP-D, and complement protein C1q are soluble innate immune pattern recognizing molecules. SP-A, SP-D and C1q have an overall similar structure composed of an N-terminal triple-helical collagen region that is followed by a trimeric globular domain. While SP-A and SP-D belong to the collectin family (collagen containing lectin), C1q is the first recognition subcomponent of the classical pathway of the complement system. Recently, SP-A, SP-D and C1q have been considered to play important roles in early and late pregnancy. However, their expression in early human decidua has not been examined. Here, we investigated whether SP-A, SP-D and C1q are expressed within first trimester decidua in humans and their expression is associated with trophoblasts and decidual stromal cells. Decidual samples from women undergoing elective vaginal termination of pregnancy during first trimester were obtained from 25 subjects. Immunohistochemical studies using anti-human SP-A, anti-human SP-D and anti-human C1q antibodies were performed on decidual tissue sections along with anti-vimentin and cytokeratin-7 antibodies to identify stromal cells and trophoblasts. The expression was also examined by immunostaining and PCR using decidual and stromal cells. C1q expression was significantly higher when compared to SP-A and SP-D in the first trimester human decidua. Double immunostaining revealed that all stromal cells and trophoblasts expressed SP-A, SP-D and C1q, while only few invasive trophoblasts expressed C1q. Thus, expression of SP-A, SP-D and C1q in human decidua during first trimester suggests potential role of SP-A, SP-D and C1q during the early stages of pregnancy including implantation, trophoblast invasion and placental development.
authors.affiliation: Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Centre for Biotechnology and Bioinformatics, School of Life Sciences, Jawaharlal Nehru Institute for Advanced Studies, Secunderabad, Andhra Pradesh, India; Centre for Infection, Immunity and Disease Mechanisms, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom.
authors.forename: Shanmuga Priyaa
authors.initials: SP
authors.lastname: Madhukaran
authors.affiliation: Centre for Infection, Immunity and Disease Mechanisms, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom.
authors.forename: Uday
authors.initials: U
authors.lastname: Kishore
authors.affiliation: Centre for Biotechnology and Bioinformatics, School of Life Sciences, Jawaharlal Nehru Institute for Advanced Studies, Secunderabad, Andhra Pradesh, India.
authors.forename: Kaiser
authors.initials: K
authors.lastname: Jamil
authors.affiliation: Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University Hospital, Singapore.
authors.forename: Mahesh
authors.initials: M
authors.lastname: Choolani
authors.affiliation: Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Electronic address: jinhua_lu@nuhs.edu.sg.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Lu
mesh_terms: D000029:Abortion, Legal; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D015922:Complement C1q / Q000235:genetics / Q000276:immunology*; D003656:Decidua / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7 / Q000235:genetics / Q000378:metabolism; D009928:Organ Specificity; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D037662:Pulmonary Surfactant-Associated Protein A / Q000235:genetics / Q000276:immunology*; D037663:Pulmonary Surfactant-Associated Protein D / Q000235:genetics / Q000276:immunology*; D017154:Stromal Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D014327:Trophoblasts / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D014746:Vimentin / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D053552:Keratin-7; D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D014746:Vimentin; D015922:Complement C1q
keywords: C1q; Decidua; Pregnancy; SP-A; SP-D; Stromal cells; Trophoblasts