Transcriptional factor PU.1 regulates decidual C1q expression in early pregnancy in human

"Copyright: © 2015 Madhukaran, Kishore, Jamil, Teo, Choolani and Lu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms."C1q is the first recognition subcomponent of the complement classical pathway, which in addition to being synthesized in the liver, is also expressed by macrophages and dendritic cells (DCs). Trophoblast invasion during early placentation results in accumulation of debris that triggers the complement system. Hence, both early and late components of the classical pathway are widely distributed in the placenta and decidua. In addition, C1q has recently been shown to significantly contribute to feto-maternal tolerance, trophoblast migration, and spiral artery remodeling, although the exact mechanism remains unknown. Pregnancy in mice, genetically deficient in C1q, mirrors symptoms similar to that of human preeclampsia. Thus, regulated complement activation has been proposed as an essential requirement for normal successful pregnancy. Little is known about the molecular pathways that regulate C1q expression in pregnancy. PU.1, an Ets-family transcription factor, is required for the development of hematopoietic myeloid lineage immune cells, and its expression is tissue-specific. Recently, PU.1 has been shown to regulate C1q gene expression in DCs and macrophages. Here, we have examined if PU.1 transcription factor regulates decidual C1q expression. We used immune-histochemical analysis, PCR, and immunostaining to localize and study the gene expression of PU.1 transcription factor in early human decidua. PU.1 was highly expressed at gene and protein level in early human decidual cells including trophoblast and stromal cells. Surprisingly, nuclear as well as cytoplasmic PU.1 expression was observed. Decidual cells with predominantly nuclear PU.1 expression had higher C1q expression. It is likely that nuclear and cytoplasmic PU.1 localization has a role to play in early pregnancy via regulating C1q expression in the decidua during implantation

Surfactant proteins SP-A and SP-D modulate uterine contractile events in ULTR myometrial cell line

Pulmonary surfactant proteins SP-A and SP-D are pattern recognition innate immune molecules. However, there is extrapulmonary existence, especially in the amniotic fluid and at the feto-maternal interface. There is sufficient evidence to suggest that SP-A and SP-D are involved in the initiation of labour. This is of great importance given that preterm birth is associated with increased mortality and morbidity. In this study, we investigated the effects of recombinant forms of SP-A and SP-D (rhSP-A and rhSP-D, the comprising of trimeric lectin domain) on contractile events in vitro, using a human myometrial cell line (ULTR) as an experimental model. Treatment with rhSP-A or rhSP-D increased the cell velocity, distance travelled and displacement by ULTR cells. rhSP-A and rhSP-D also affected the contractile response of ULTRs when grown on collagen matrices showing reduced surface area. We investigated this effect further by measuring contractility-associated protein (CAP) genes. Treatment with rhSP-A and rhSP-D induced expression of oxytocin receptor (OXTR) and connexin 43 (CX43). In addition, rhSP-A and rhSP-D were able to induce secretion of GROα and IL-8. rhSP-D also induced the expression of IL-6 and IL-6 Ra. We provide evidence that SP-A and SP-D play a key role in modulating events prior to labour by reconditioning the human myometrium and in inducing CAP genes and pro-inflammatory cytokines thus shifting the uterus from a quiescent state to a contractile one

Role of Collectins and Complement Protein C1q in pregnancy and parturition

Collectins such as surfactant proteins SP-A, SP-D, and mannan-binding lectin (MBL), as well as complement protein C1q are evolutionarily conserved innate immune molecules. They are known to opsonize a range of microbial pathogens (bacteria, fungi, virus, and parasites) and trigger effector clearance mechanisms involving phagocytosis and/or complement activation. Collectins and C1q have also attracted attention in studies involving pregnancy as they are expressed in the female reproductive tissues during pregnancy; a unique state of immune suppression with increased susceptibility to infectious diseases. Recent studies are beginning to unravel their functional significance in implantation, placentation, pregnancy maintenance and parturition in normal and adverse pregnancies. Collectins and C1q, expressed in gestational tissues during pregnancy, might alter the status of mother’s immune response to the allogenic fetus and the microenvironment, thereby serving as important regulators of fetus-mother interaction. Here, we discuss the functional roles that have been assigned to SPA, SP-D, MBL and C1q in pregnancy and parturition

Protein-protein interaction between surfactant protein D and DC-SIGN via C-type lectin domain can suppress HIV-1 transfer

Surfactant protein SP-D is a soluble C-type lectin, belonging to the collectin (collagencontaining calcium-dependent lectin) family, which acts as an innate immune pattern recognition molecule in the lungs and other mucosal surfaces. Immune regulation and surfactant homeostasis are salient functions of SP-D. SP-D can bind to a range of viral, bacterial and fungal pathogens and trigger clearance mechanisms. SP-D binds to gp120, the envelope protein expressed on HIV-1, through its C-type lectin or carbohydrate recognition domain (CRD). This is of importance since SP-D is secreted by human mucosal epithelial cells and is present in the female reproductive tract including vagina. Another C-type lectin, Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin (DCSIGN), present on the surface of the dendritic cells, also binds to HIV-1 gp120 and facilitates viral transfer to the lymphoid tissues. Dendritic cells are also present at the site of HIV-1 entry, embedded in vaginal or rectal mucosa. In the present study, we report a direct proteinprotein interaction between recombinant forms of SP-D (rfhSP-D) and DC-SIGN via their Ctype lectin domains. Both SP-D and DC-SIGN competed for binding to immobilized HIV-1 gp120. Pre-incubation of Human Embryonic Kidney (HEK) cells expressing surface DCSIGN with rfhSP-D significantly inhibited the HIV-1 transfer to activated PBMCs. In silico analysis revealed that SP-D and gp120 may occupy same sites on DC-SIGN, which may explain the reduced transfer of HIV-1. In summary, we demonstrate, for the first time, that DC-SIGN is a novel binding partner of SP-D, and this interaction can modulate HIV-1 capture and transfer to CD4+ T cells. In addition, the present study also reveals a distinct mechanism of host defense by SP-D against HIV-1

C1 complex: An adaptable proteolytic module for complement and non-complement functions

Complement C1 is the defining component of the classical pathway. Within the C1qC1r2C1s2 complex, C1q functions as a molecular scaffold for C1r2C1s2 and C1q binding to its ligands activates these two serine proteases. The classic C1q ligands are antigen-bound antibodies and activated C1s cleaves C4 and C2 to initiate the complement cascade. Recent studies suggest broad C1 functions beyond the complement system. C1q binds to the Frizzled receptors to activate C1s, which cleaves lipoprotein receptor-related protein 6 to trigger aging-associated Wnt receptor signaling. C1q binds to apoptotic cells and the activated C1 proteases cleave nuclear antigens. C1s also cleaves MHC class I molecule and potentially numerous other proteins. The diversity of C1q ligands and C1 protease substrates renders C1 complex versatile and modular so that it can adapt to multiple molecular and cellular processes besides the complement system

A Comparative Study of Pre Engineering Building by Working Stress Method and Limit State Method in Terms of Weight in Different Topographs: A Case Study

In recent years the introduction of the pre-engineered buildings (PEB) concept in the design of structures made and designs in a much optimized way. The Pre Engineering Steel Building Structures have many advantages as compared to Conventional steel buildings in terms of weight and economy, by designing IS codes of IS 800-1984 and 2007 . In this study a structure width 48m, length 96m with clear height 7m and has Roof-slope 1:10, analysed and design is carried out considering 2D frames (end frame, frame without crane). The economy of the structure is discussed in in terms of its weight comparison between IS 800-1984 (WSM) & IS 800-2007(LSM), and also structure is analysed and designed in terms of weight in different wind zones

Protocol to dissociate epithelia from non-pregnant and pregnant mouse cervical tissue for single-cell RNA-sequencing

Summary: A challenge in studying cervical epithelial cell biology at the single-cell level is that differentiated subtypes, in particular mucus-secreting goblet cells, are sensitive to disassociating enzymes making isolation of all epithelial subpopulations difficult. Here we present a protocol to dissociate epithelia from non-pregnant and pregnant mouse cervical tissue for single-cell RNA-sequencing. We describe steps for harvesting cervices, preparing cervical tissue, dissociation of cervical cells, and viability checks. We then detail library preparation, sequencing, and procedure for data analysis.For complete details on the use and execution of this protocol, please refer to Cooley et al. (2023).1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics

Performance Evaluation of Multi-Storey Symmetric and Asymmetric Flat Slab Structures and Conventional Slab Structures

In the present study we have modelled symmetric conventional slab building, asymmetric conventional slab buildings and symmetric flat slab building, asymmetric flat slab building such as H-shape, L-shape, Long slender shape, Rectangular shape, T shape buildings for G+5, G+10 and G+15 stories using ETABS 9.7.4.2 non-linear version software. We have compared base shear, lateral displacement and story drift values for linear static analysis and Response spectrum analysis. And we have observed that symmetric buildings are comparatively more suitable to take earthquake load compared to asymmetric buildings