Design of self-assembly dipeptide hydrogels and machine learning via their chemical features.

Hydrogels that are self-assembled by peptides have attracted great interest for biomedical applications. However, the link between chemical structures of peptides and their corresponding hydrogel properties is still unclear. Here, we showed a combinational approach to generate a structurally diverse hydrogel library with more than 2,000 peptides and evaluated their corresponding properties. We used a quantitative structure-property relationship to calculate their chemical features reflecting the topological and physicochemical properties, and applied machine learning to predict the self-assembly behavior. We observed that the stiffness of hydrogels is correlated with the diameter and cross-linking degree of the nanofiber. Importantly, we demonstrated that the hydrogels support cell proliferation in culture, suggesting the biocompatibility of the hydrogel. The combinatorial hydrogel library and the machine learning approach we developed linked the chemical structures with their self-assembly behavior and can accelerate the design of novel peptide structures for biomedical use.

Retinoic acid promotes stem cell differentiation and embryonic development by transcriptionally activating CFTR.

Retinoic acid (RA) plays a pivotal role in many cellular processes; however, the signaling mechanisms mediating the effect of RA are not fully understood. Here, we show that RA transcriptionally upregulates cystic fibrosis transmembrane conductance regulator (Cftr) by promoting the direct binding of its receptor RARα to Cftr promoter in mouse spermatogonia and embryonic stem (ES) cells. The RA/CFTR pathway is involved in the differentiation of spermatogonia and organogenesis during the embryo development of Xenopus laevis. Loss of CFTR by siRNA-mediated knockdown blunts the RA-induced spermatogonial differentiation. Overexpression of CFTR mimics the effect of RA on the induction of spermatogonial differentiation or restores the developmental defects induced by the knockdown of RARα in spermatogonial cells and Xenopus laevis. Analysis of the human database shows that the expression of CFTR positively correlates with RARα in brain tissues, stem cells as well as cancers, supporting the role of RA/CFTR pathway in various developmental processes in humans. Together, our study discovers an essential role of CFTR in mediating the RA-dependent signaling for stem cell differentiation and embryonic development.

Novel regulators of spermatogenesis.

Spermatogenesis is a multistep process that supports the production of millions of sperm daily. Understanding of the molecular mechanisms that regulate spermatogenesis has been a major focus for decades. Yet, the regulators involved in different cellular processes of spermatogenesis remain largely unknown. Human diseases that result in defective spermatogenesis have provided hints on the molecular mechanisms regulating this process. In this review, we have summarized recent findings on the function and signaling mechanisms of several genes that are known to be associated with disease or pathological processes, including CFTR, CD147, YWK-II and CT genes, and discuss their potential roles in regulating different processes of spermatogenesis.

Downregulation of CFTR promotes epithelial-to-mesenchymal transition and is associated with poor prognosis of breast cancer.

The epithelial-to-mesenchymal transition (EMT), a process involving the breakdown of cell-cell junctions and loss of epithelial polarity, is closely related to cancer development and metastatic progression. While the cystic fibrosis transmembrane conductance regulator (CFTR), a Cl(-) and HCO3(-) conducting anion channel expressed in a wide variety of epithelial cells, has been implicated in the regulation of epithelial polarity, the exact role of CFTR in the pathogenesis of cancer and its possible involvement in EMT process have not been elucidated. Here we report that interfering with CFTR function either by its specific inhibitor or lentiviral miRNA-mediated knockdown mimics TGF-ß1-induced EMT and enhances cell migration and invasion in MCF-7. Ectopic overexpression of CFTR in a highly metastatic MDA-231 breast cancer cell line downregulates EMT markers and suppresses cell invasion and migration in vitro, as well as metastasis in vivo. The EMT-suppressing effect of CFTR is found to be associated with its ability to inhibit NFκB targeting urokinase-type plasminogen activator (uPA), known to be involved in the regulation of EMT. More importantly, CFTR expression is found significantly downregulated in primary human breast cancer samples, and is closely associated with poor prognosis in different cohorts of breast cancer patients. Taken together, the present study has demonstrated a previously undefined role of CFTR as an EMT suppressor and its potential as a prognostic indicator in breast cancer.

Regulation of apoptosis by Bat3-enhanced YWK-II/APLP2 protein stability.

YWK-II protein/APLP2 is a member of an evolutionarily conserved protein family that includes amyloid precursor protein (APP) and amyloid precursor-like protein-1 (APLP1). We have previously demonstrated that YWK-II/APLP2 functions as a novel G(0)-protein-coupled receptor for Müllerian inhibiting substance (MIS) in cell survival. However, factors regulating the stability and turnover of YWK-II/APLP2 have not been identified. Here we present evidence that human leukocyte antigen-B-associated transcript 3 (Bat3), an important regulator involved in apoptosis, can interact with YWK-II/APLP2 and enhance its stability by reducing its ubiquitylation and degradation by the ubiquitin-proteasome system. Coexpression of different Bat3 domain deletion constructs with YWK-II/APLP2 reveals that the proline-rich domain of Bat3 is required for its binding to YWK-II/APLP2. In addition, we find that the protein levels of YWK-II/APLP2 could be enhanced by nuclear export of Bat3 under apoptotic stimulation. We also find elevated levels of Bat3 and YWK-II/APLP2 in human colorectal cancer with a positive correlation between the two. Taken together, these results have revealed a previously undefined mechanism regulating cell apoptosis and suggest that aberrant enhancement of YWK-II/APLP2 by nuclear export of Bat3 may play a role in cancer development by inhibiting cell apoptosis.

Decreased expression of cystic fibrosis transmembrane conductance regulator impairs sperm quality in aged men.

Sperm quality declines with aging; however, the underlying molecular mechanism remains elusive. The cystic fibrosis transmembrane conductance regulator (CFTR) has been shown to play an essential role in fertilizing capacity of sperm and male fertility. This study aimed to investigate the involvement of age-dependent CFTR downregulation in lowering sperm quality in old age. Two hundred and one healthy fertile men of three age groups (20-40 years, n=64; 40-60 years, n=61; and >60 years, n=76) were recruited. Expression of CFTR was determined by RT-PCR, western blot, and immunofluorescence staining. Collected sperm were treated with CFTR inhibitor or potentiator. Sperm quality was assessed by motility and bicarbonate-induced capacitation. The results showed that the expression of CFTR on the equatorial segment and neck region of sperm was significantly decreased in an age-dependent manner. Reduction of CFTR expression in sperm from old men was correlated with lowered forward motility and decreased HCO3(-) sensitivity required for sperm capacitation. Activation of CFTR by genistein partially rescued the decreased forward motility in sperm from old men. Decreased CFTR expression in sperm was also found to be associated with lowered sperm quality in aging mice. These results suggest that age-dependent downregulation of CFTR in sperm leads to lowered sperm quality in old age sperm. CFTR may be a pontential target for rescuing sperm motility as well as a fertility indicator in old age men.

Epididymis cell atlas in a patient with a sex development disorder and a novel NR5A1 gene mutation.

This study aims to characterize the cell atlas of the epididymis derived from a 46,XY disorders of sex development (DSD) patient with a novel heterozygous mutation of the nuclear receptor subfamily 5 group A member 1 (NR5A1) gene. Next-generation sequencing found a heterozygous c.124C>G mutation in NR5A1 that resulted in a p.Q42E missense mutation in the conserved DNA-binding domain of NR5A1. The patient demonstrated feminization of external genitalia and Tanner stage 1 breast development. The surgical procedure revealed a morphologically normal epididymis and vas deferens but a dysplastic testis. Microfluidic-based single-cell RNA sequencing (scRNA-seq) analysis found that the fibroblast cells were significantly increased (approximately 46.5%), whereas the number of main epididymal epithelial cells (approximately 9.2%), such as principal cells and basal cells, was dramatically decreased. Bioinformatics analysis of cell-cell communications and gene regulatory networks at the single-cell level inferred that epididymal epithelial cell loss and fibroblast occupation are associated with the epithelial-to-mesenchymal transition (EMT) process. The present study provides a cell atlas of the epididymis of a patient with 46,XY DSD and serves as an important resource for understanding the pathophysiology of DSD.

STK31 maintains the undifferentiated state of colon cancer cells.

The expression of serine/threonine kinase (STK) family is frequently altered in human cancers. However, the functions of these kinases in cancer development remain elusive. Here, we report that STK31 is robustly and heterogeneously expressed in colon cancer tissues and plays a critical role in determining the differentiation state of colon cancer cells. Knockdown or overexpression of STK31 induced or inhibited differentiation of colon cancer cells, respectively. Deletion of the STK domain abolished the inhibiting effect of STK31. Associated with differentiation, knockdown of STK31 resulted in significant suppression of tumorigenicity both in vitro and in vivo. Genome microarray analysis showed that knockdown of STK31 altered the expression profile of genes that are known to be involved in germ cell and cancer differentiation. Taken together, these results suggest that STK31 is able to control the differentiation state of colon cancer cells, which critically depends on its STK domain. The present findings may shed light on the new therapeutic approach against cancer by targeting STK31 and cancer differentiation.

Lymphocyte CFTR promotes epithelial bicarbonate secretion for bacterial killing.

The expression of cystic fibrosis transmembrane conductance regulator (CFTR) in lymphocytes has been reported for nearly two decades; however, its physiological role remains elusive. Here, we report that co-culture of lymphocytes with lung epithelial cell line, Calu-3, promotes epithelial HCO(3)- production/secretion with up-regulated expression of carbonic anhydrase 2 and 4 (CA-2, CA-4) and enhanced bacterial killing capability. The lymphocyte-enhanced epithelial HCO(3)- secretion and bacterial killing activity was abolished when Calu3 cells were co-cultured with lymphocytes from CFTR knockout mice, or significantly reduced by interfering with E-cadherin, a putative binding partner of CFTR. Bacterial lipopolysaccharide (LPS)-induced E-cadherin and CA-4 expression in the challenged lung was also found to be impaired in CFTR knockout mice compared to that of the wild-type. These results suggest that the interaction between lymphocytes and epithelial cells may induce a previously unsuspected innate host defense mechanism against bacterial infection by stimulating epithelial HCO(3)- production/secretion, which requires CFTR expression in lymphocytes.

Cryptorchidism-induced CFTR down-regulation results in disruption of testicular tight junctions through up-regulation of NF-κB/COX-2/PGE2.

STUDY QUESTION: Does elevated temperature-induced cystic fibrosis transmembrane conductance regulator (CFTR) down-regulation in Sertoli cells in cryptorchid testis disrupt testicular tight junctions (TJs) through the nuclear factor kappa B (NF-κB)/cyclooxygenase-2 (COX-2)/prostaglandin E(2) (PGE(2)) pathway? SUMMARY ANSWER: Our results suggest that CFTR may be involved in regulating testicular TJs and the blood-testis barrier (BTB) through its negative regulation of the NF-κB/COX-2/PGE(2) pathway in Sertoli cells, a defect of which may result in the spermatogenesis defect in cryptorchidism. WHAT IS KNOWN ALREADY: Cryptorchidism, or undescended testes, is known to result in defective spermatogenesis. Although an elevated testicular temperature is regarded as an important factor affecting spermatogenesis in cryptorchidism, the exact mechanism remains elusive. It is known that the expression of functional CFTR is temperature sensitive. Our previous study has demonstrated that CFTR negatively regulates NF-κB/COX-2/PGE(2) in bronchial epithelial cells. Disruption of TJs by COX-2/PGE(2) has been found in tumour cells. STUDY DESIGN AND METHODS: Expression of CFTR, NF-κB, COX-2 and TJ proteins was examined in the testes of a surgical-induced cryptorchidism mouse model and a testicular hyperthermia mouse model, as well as in control or CFTR-inhibited/knocked down primary rat Sertoli cells. PGE(2) production was measured by ELISA. Sertoli cell barrier function was determined by transepethelial resistance (TER) measurements in rat Sertoli cell primary cultures. BTB integrity in the cryptorchidism model was monitored by examining tracker dye injected into seminiferous tubules. MAIN RESULTS: Down-regulation of CFTR accompanied by activation of NF-κB, up-regulation of COX-2 and down-regulation of TJ proteins, including ZO-1 and occludin, was observed in a cryptorchidism mouse model. BTB leakage revealed impaired BTB integrity in cryptorchid testes, confirming the destruction of TJs. The inverse correlation of CFTR and COX-2 was further confirmed in a mouse testis hyperthermia model and CFTR knockout mouse model. Culturing primary Sertoli cells at 37°C, which mimics the pathological condition of cryptorchidism, led to a significant decrease in CFTR and increase in COX-2 expression and PGE(2) production compared with the culture at the physiological 32°C. Inhibition or knockdown of CFTR led to increased COX-2 but decreased ZO-1 and occludin expression in Sertoli cells, which could be mimicked by PGE(2), but reversed by NF-κB or COX-2 inhibitor, suggesting that the regulation of TJs by CFTR is mediated by a NF-κB/COX-2/PGE(2) pathway. Inhibition of CFTR or administration of PGE(2) significantly decreased Sertoli cell TER. LIMITATIONS: This study has tested only the CFTR/NF-κB/COX-2/PGE(2) pathway in mouse testes in vivo and in rat Sertoli cells in vitro, and thus, it has some limitations. Further investigations in other species, especially humans, are needed. WIDER IMPLICATIONS OF THE FINDINGS: Our study may shed more light on one of the aspects of the complicated underlying mechanisms of defective spermatogenesis induced by cryptorchidism.

CD147 regulates apoptosis in mouse spermatocytes but not spermatogonia.

BACKGROUND: Spermatogenesis is maintained by a dynamic balance between germ cell proliferation and apoptosis. Previous study has demonstrated that CD147 knockout mice are infertile with arrested germ cells. However, the question of whether and how CD147 may be involved in the apoptotic process during spermatogenesis remains elusive. The aim of this study was to evaluate the role of CD147 in the regulation of germ cell apoptosis in mice. METHODS: CD147 function was blocked by anti-CD147 antibody in GC-1 (immortalized spermatogonia) and GC-2 (immortalized spermatocytes) cell lines and in testicular germ cells in vivo. Testes size and weight were examined after injection of anti-CD147 antibody into the seminiferous tubules of severe combined immunodeficiency mice. Germ cell apoptosis was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and levels of p53 and two effectors, caspase 3 and poly ADP-ribose polymerase (PARP), using western blots. RESULTS: The size and weight of the CD147-immunodepleted testes were decreased compared with that in control testes (P < 0.001). The TUNEL assay showed an increase in the number of apoptotic spermatocytes (P < 0.001 versus control) but not spermatogonia in Stages XI-XII of CD147-immunodepleted testes. In addition, in vitro experiments demonstrated that CD147 immunodepletion induced an increase in apoptosis in GC-2 cells (P < 0.001 versus control) but had no effect on GC-1 cells. Moreover, deprivation of CD147 induced apoptosis in spermatocytes through a p53-independent mechanism, which led to caspase 3 and PARP activation. CONCLUSIONS: We have demonstrated that immunodepletion of CD147 induces p53-independent apoptosis in mouse spermatocytes but not spermatogonia.

Dedifferentiation-reprogrammed mesenchymal stem cells with improved therapeutic potential.

Stem cell transplantation has been shown to improve functional outcome in degenerative and ischemic disorders. However, low in vivo survival and differentiation potential of the transplanted cells limits their overall effectiveness and thus clinical usage. Here we show that, after in vitro induction of neuronal differentiation and dedifferentiation, on withdrawal of extrinsic factors, mesenchymal stem cells (MSCs) derived from bone marrow, which have already committed to neuronal lineage, revert to a primitive cell population (dedifferentiated MSCs) retaining stem cell characteristics but exhibiting a reprogrammed phenotype distinct from their original counterparts. Of therapeutic interest, the dedifferentiated MSCs exhibited enhanced cell survival and higher efficacy in neuronal differentiation compared to unmanipulated MSCs both in vitro and in vivo, with significantly improved cognition function in a neonatal hypoxic-ischemic brain damage rat model. Increased expression of bcl-2 family proteins and microRNA-34a appears to be the important mechanism giving rise to this previously undefined stem cell population that may provide a novel treatment strategy with improved therapeutic efficacy.

Flavonoid Myricetin Modulates GABA(A) Receptor Activity through Activation of Ca(2+) Channels and CaMK-II Pathway.

The flavonoid myricetin is found in several sedative herbs, for example, the St. John's Wort, but its influence on sedation and its possible mechanism of action are unknown. Using patch-clamp technique on a brain slice preparation, the present study found that myricetin promoted GABAergic activity in the neurons of hypothalamic paraventricular nucleus (PVN) by increasing the decay time and frequency of the inhibitory currents mediated by GABA(A) receptor. This effect of myricetin was not blocked by the GABA(A) receptor benzodiazepine- (BZ-) binding site antagonist flumazenil, but by KN-62, a specific inhibitor of the Ca(2+)/calmodulin-stimulated protein kinase II (CaMK-II). Patch clamp and live Ca(2+) imaging studies found that myricetin could increase Ca(2+) current and intracellular Ca(2+) concentration, respectively, via T- and L-type Ca(2+) channels in rat PVN neurons and hypothalamic primary culture neurons. Immunofluorescence staining showed increased phosphorylation of CaMK-II after myricetin incubation in primary culture of rat hypothalamic neurons, and the myricetin-induced CaMK-II phosphorylation was further confirmed by Western blotting in PC-12 cells. The present results suggest that myricetin enhances GABA(A) receptor activity via calcium channel/CaMK-II dependent mechanism, which is distinctively different from that of most existing BZ-binding site agonists of GABA(A) receptor.

The N501Y Mutation of SARS-CoV-2 Spike Protein Impairs Spindle Assembly in Mouse Oocytes.

The COVID-19 pandemic has been continuing for one and a half year and caused a profound effect on human health. Although advanced researches and literatures are gathered, the influences of SARS-CoV-2 on the reproduction systems are largely unknown, especially on the female reproductive functions. The purpose of this study was to investigate the effect of N501Y mutant spike protein of SARS-Cov-2 on oocyte maturation. We demonstrated that the N501Y mutant of SARS-CoV-2 spike protein impaired the mouse oocyte maturation accompanied by abnormal spindle assembly. Furthermore, the mean spindle length and the plate width were significantly increased in the N501Y-treated group compared to the control group. These results indicated the potential impairment of maturation of the oocytes caused by the infection of SARS-CoV-2, albeit current results were derived from mouse oocytes. The present study provided a theoretical basis for the attention of female reproductive health during the COVID-19 pandemic and shed light on the potential risk of SARS-CoV-2 in the successful rate of assisted reproduction.

Defb19 regulates the migration of germ cell and is involved in male fertility.

ß-defensins are small antimicrobial peptides that play essential roles in male fertility. Although several members of the ß-defensin family are preferentially expressed in the testis, their involvement in spermatogenesis remains elusive. In this study, we have characterized the expression and function of Defb19 in mouse testis. Our results showed that Defb19 is expressed in both Sertoli cells and germ cells. Overexpression of Defb19 in the 15P-1 Sertoli cell line decreases the expression of cell junction molecules and promotes the matrix adhesion and migration of Sertoli cells. Recombinant DEFB19 and conditioned medium of Defb19-overexpressed 15P-1 cells promote the migration of GC2-spd spermatocyte cell line. Knockout of Defb19 in mouse by CRISPR/Cas9 resulted in male subfertility with testicular and epididymal atrophy. A marked increase in apoptosis and a significant decrease in the sperm count were observed in the KO mice. Together, our study has uncovered an important role of Defb19 in male fertility by regulating the migration of both the Sertoli cells and the germ cells. Our study has shed new light on the functions of ß-defensins in the testis.

Interfering with CSE1L/CAS inhibits tumour growth via C3 in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer. However, the treatment regimens for TNBC are limited. Chromosome segregation 1-like (CSE1L), also called cellular apoptosis susceptibility protein (CAS), is highly expressed in breast cancer and plays a crucial role in the progression of various tumours. However, the involvement of CAS in TNBC remains elusive. In this study, we showed that the expression of CAS was higher in TNBC samples than in non-TNBC samples in the Gene Expression Omnibus database. Knockdown of CAS inhibited MDA-MB-231 cell growth, migration and invasion. Further RNA-seq analysis revealed that complement pathway activity was significantly elevated. Of note, complement component 3 (C3), the key molecule in the complement pathway, was significantly upregulated, and the expression of C3 was negatively correlated with that of CAS in breast cancer. Lower C3 expression was related to poor prognosis. Interestingly, the expression level of C3 was positively correlated with the infiltration of multiple immune cells. Taken together, our findings suggest that CAS participates in the development of TNBC through C3-mediated immune cell suppression and might constitute a potential therapeutic target for TNBC.

ß-Defensin 19/119 mediates sperm chemotaxis and is associated with idiopathic infertility.

Sperm chemotaxis is required for guiding sperm toward the egg. However, the molecular identity of physiological chemoattractant and its involvement in infertility remain elusive. Here, we identify DEFB19/119 (mouse/human orthologs) as a physiological sperm chemoattractant. The epithelia of the female reproductive tract and the cumulus-oocyte complex secrete DEFB19/119 that elicits calcium mobilization via the CatSper channel and induces sperm chemotaxis in capacitated sperm. Manipulating the level of DEFB19 in mice determines the number of sperm arriving at the fertilization site. Importantly, we identify exon mutations in the DEFB119 gene in idiopathic infertile women with low level of DEFB119 in the follicular fluid. The level of DEFB119 correlates with the chemotactic potency of follicular fluid and predicts the infertile outcome with positive correlation. This study reveals the pivotal role of DEFB19/119 in sperm chemotaxis and demonstrates its potential application in the diagnosis of idiopathic infertility.

CD147 is required for matrix metalloproteinases-2 production and germ cell migration during spermatogenesis.

Spermatogenesis is a highly programmed process that requires the degradation of the extracellular matrix and the remodeling of tight junctions (TJ) to facilitate differentiating germ cell migration. Matrix metalloproteinases (MMPs) are essential in regulating Sertoli cell TJ in the testis. CD147 is known to stimulate the production of MMPs in tumor metastasis and its knockout mice are infertile. However, the functional relationship between CD147 and MMPs in spermatogenesis has not been investigated. In the present study, we examined the expression profile of CD147 and MMPs during mouse testicular development by RT-PCR, western blot and immunofluorescence staining. We also examined CD147 involvement in the production of MMP-2 and the migration of germ cells (GC-1 and GC-2 cells) using CD147 antibody or synthetic microRNA mimics-mediated knockdown. The results showed that CD147 was present at all stages of testicular development from 7 to 56 days post-partum (dpp). CD147 expression was found to increase after 21 days from moderate levels in 7 and 14 days. Of the eight MMPs studied, MMP-2, MMP-7, MMP-9 and MMP-23 were detected to have changes in expression during testicular development, with MMP-2 showing the largest change. CD147 and MMP-2 were co-localized in spermatogonia, spermatocytes and round spermatids in mouse testis, while in human testis, they were co-localized in spermatocytes and round spermatids. MMP-2 expression and migration of GC-1 and GC-2 cells were reduced by interfering with CD147 expression and function in vitro. These data suggest that CD147 regulates migration of spermatogonia and spermatocytes via induction of MMP-2 production during spermatogenesis.

Spatio-temporal landscape of mouse epididymal cells and specific mitochondria-rich segments defined by large-scale single-cell RNA-seq.

Spermatozoa acquire their fertilizing ability and forward motility during epididymal transit, suggesting the importance of the epididymis. Although the cell atlas of the epididymis was reported recently, the heterogeneity of the cells and the gene expression profile in the epididymal tube are still largely unknown. Considering single-cell RNA sequencing results, we thoroughly studied the cell composition, spatio-temporal differences in differentially expressed genes (DEGs) in epididymal segments and mitochondria throughout the epididymis with sufficient cell numbers. In total, 40,623 cells were detected and further clustered into 8 identified cell populations. Focused analyses revealed the subpopulations of principal cells, basal cells, clear/narrow cells, and halo/T cells. Notably, two subtypes of principal cells, the Prc7 and Prc8 subpopulations were enriched as stereocilia-like cells according to GO analysis. Further analysis demonstrated the spatially specific pattern of the DEGs in each cell cluster. Unexpectedly, the abundance of mitochondria and mitochondrial transcription (MT) was found to be higher in the corpus and cauda epididymis than in the caput epididymis by scRNA-seq, immunostaining, and qPCR validation. In addition, the spatio-temporal profile of the DEGs from the P42 and P56 epididymis, including transiting spermatozoa, was depicted. Overall, our study presented the single-cell transcriptome atlas of the mouse epididymis and revealed the novel distribution pattern of mitochondria and key genes that may be linked to sperm functionalities in the first wave and subsequent wave of sperm, providing a roadmap to be emulated in efforts to achieve sperm maturation regulation in the epididymis.

CD147 deficiency is associated with impairedsperm motility/acrosome reaction and offersa therapeutic target for asthenozoospermia.

Patients with asthenozoospermia often present multiple defects in sperm functions apart from a decrease in sperm motility. However, the etiological factors underlying these multifaceted defects remain mostly unexplored, which may lead to unnecessary treatment and unsatisfactory assisted reproductive technologies (ART) outcome. Here, we show that the protein levels of CD147 were lowered in sperm obtained from asthenozoospermic infertile patients exhibiting defects in both sperm motility and the acrosome reaction. Whereas CD147 maintained sperm motility before capacitation, female tract-derived soluble CD147 interacted with sperm-bound CD147 to induce an acrosome reaction in capacitated sperm. Soluble CD147 treatment restored the acrosome reaction and improved the fertility of sperm from patients with asthenozoospermia. Mechanistically, CD147 promotes sperm motility and acrosome reaction (AR) by eliciting Ca2+ influx through soluble CD147 binding to sperm-bound CD147. Notably, the level of soluble CD147 in seminal plasma was positively correlated with the fertilization rate and pregnancy outcome in infertile couples undergoing in vitro fertilization. Our study has identified a marker for the diagnosis and a therapeutic target for the defective AR capability in asthenozoospermia and a candidate for the prediction of in vitro fertilization outcomes for male infertile patients that facilitates the development of precision medicine in ART.