Deciphering cell signaling networks with massively multiplexed biosensor barcoding.

Genetically encoded fluorescent biosensors are powerful tools for monitoring biochemical activities in live cells, but their multiplexing capacity is limited by the available spectral space. We overcome this problem by developing a set of barcoding proteins that can generate over 100 barcodes and are spectrally separable from commonly used biosensors. Mixtures of barcoded cells expressing different biosensors are simultaneously imaged and analyzed by deep learning models to achieve massively multiplexed tracking of signaling events. Importantly, different biosensors in cell mixtures show highly coordinated activities, thus facilitating the delineation of their temporal relationship. Simultaneous tracking of multiple biosensors in the receptor tyrosine kinase signaling network reveals distinct mechanisms of effector adaptation, cell autonomous and non-autonomous effects of KRAS mutations, as well as complex interactions in the network. Biosensor barcoding presents a scalable method to expand multiplexing capabilities for deciphering the complexity of signaling networks and their interactions between cells.

Multimodally profiling memory T cells from a tuberculosis cohort identifies cell state associations with demographics, environment and disease.

Multimodal T cell profiling can enable more precise characterization of elusive cell states underlying disease. Here, we integrated single-cell RNA and surface protein data from 500,089 memory T cells to define 31 cell states from 259 individuals in a Peruvian tuberculosis (TB) progression cohort. At immune steady state >4 years after infection and disease resolution, we found that, after accounting for significant effects of age, sex, season and genetic ancestry on T cell composition, a polyfunctional type 17 helper T (TH17) cell-like effector state was reduced in abundance and function in individuals who previously progressed from Mycobacterium tuberculosis (M.tb) infection to active TB disease. These cells are capable of responding to M.tb peptides. Deconvoluting this state-uniquely identifiable with multimodal analysis-from public data demonstrated that its depletion may precede and persist beyond active disease. Our study demonstrates the power of integrative multimodal single-cell profiling to define cell states relevant to disease and other traits.

History of tuberculosis disease is associated with genetic regulatory variation in Peruvians.

A quarter of humanity is estimated to have been exposed to Mycobacterium tuberculosis (Mtb) with a 5-10% risk of developing tuberculosis (TB) disease. Variability in responses to Mtb infection could be due to host or pathogen heterogeneity. Here, we focused on host genetic variation in a Peruvian population and its associations with gene regulation in monocyte-derived macrophages and dendritic cells (DCs). We recruited former household contacts of TB patients who previously progressed to TB (cases, n = 63) or did not progress to TB (controls, n = 63). Transcriptomic profiling of monocyte-derived DCs and macrophages measured the impact of genetic variants on gene expression by identifying expression quantitative trait loci (eQTL). We identified 330 and 257 eQTL genes in DCs and macrophages (False Discovery Rate (FDR) < 0.05), respectively. Four genes in DCs showed interaction between eQTL variants and TB progression status. The top eQTL interaction for a protein-coding gene was with FAH, the gene encoding fumarylacetoacetate hydrolase, which mediates the last step in mammalian tyrosine catabolism. FAH expression was associated with genetic regulatory variation in cases but not controls. Using public transcriptomic and epigenomic data of Mtb-infected monocyte-derived dendritic cells, we found that Mtb infection results in FAH downregulation and DNA methylation changes in the locus. Overall, this study demonstrates effects of genetic variation on gene expression levels that are dependent on history of infectious disease and highlights a candidate pathogenic mechanism through pathogen-response genes. Furthermore, our results point to tyrosine metabolism and related candidate TB progression pathways for further investigation.

Circular RNAs in physiology and non-immunological diseases.

Circular RNAs (circRNAs) are covalently closed single-stranded RNAs. Four subclasses of circRNAs have been identified in animal cells, and they have unique features in their biogenesis, degradation, and transport. CircRNAs have diverse molecular functions in sponging miRNAs, regulating transcription, modulating RNA-binding proteins, and even encoding proteins. Some circRNAs are important regulators of various physiological processes to maintain homeostasis. Dysregulation of circRNAs is associated with human disorders, and individual circRNAs are crucial factors that contribute to major diseases including non-immunological diseases such as cancers, neurological disorders, cardiovascular disease, and metabolic disease. Debates on circRNAs have also been raised in recent years, and further studies would help to resolve these disputes and potentially lead to biomedical applications of circRNAs.

A circular RNA-gawky-chromatin regulatory axis modulates stress-induced transcription.

In response to heavy metal stress, the RNA-binding protein (RBP) gawky translocates into the nucleus and acts as a chromatin-interacting factor to activate the transcription of many stress-responsive genes. However, the upstream regulators of gawky-mediated transcription and their mechanistic details remain unknown. Here, we identified a class of metal-responsive element-containing circRNAs (MRE circRNAs) which specifically interact with gawky during copper stress. Using classic stress-responsive genes as a readout (Drosophila MT), we found that overexpression of MRE circRNAs led to a significant repression in stress-induced transcription. Mechanistically, MRE circRNAs promote the dissociation of gawky from chromatin and increase its aberrant cytoplasmic accumulation, which ultimately impedes the loading of RNA polymerase II to the active gene loci. The MRE motif serves as an important RNA regulon for maintaining the circRNA-gawky interaction, loss of which impaired the inhibitory effects of MRE circRNAs on gawky. Through RNA-seq analyses, we then identified over 500 additional stress-responsive genes whose induced transcription was attenuated upon MRE circRNA overexpression. Finally, we uncovered the physiological relevance of MRE circRNA-mediated regulation in cellular defense against copper overloading. Taken together, this study proposes that the circRNA-RBP-chromatin axis may represent a fundamental regulatory network for gene expression in eukaryotic cells.

A length-dependent evolutionarily conserved pathway controls nuclear export of circular RNAs.

Circular RNAs (circRNAs) are generated from many protein-coding genes. Most accumulate in the cytoplasm, but how circRNA localization or nuclear export is controlled remains unclear. Using RNAi screening, we found that depletion of the Drosophila DExH/D-box helicase Hel25E results in nuclear accumulation of long (>800-nucleotide), but not short, circRNAs. The human homologs of Hel25E similarly regulate circRNA localization, as depletion of UAP56 (DDX39B) or URH49 (DDX39A) causes long and short circRNAs, respectively, to become enriched in the nucleus. These data suggest that the lengths of mature circRNAs are measured to dictate the mode of nuclear export.

Aerobic training attenuates cardiac remodeling in mice post-myocardial infarction by inhibiting the p300/CBP-associated factor.

Aerobic training (AT), an effective form of cardiac rehabilitation, has been shown to be beneficial for cardiac repair and remodeling after myocardial infarction (MI). The p300/CBP-associated factor (PCAF) is one of the most important lysine acetyltransferases and is involved in various biological processes. However, the role of PCAF in AT and AT-mediated cardiac remodeling post-MI has not been determined. Here, we found that the PCAF protein level was significantly increased after MI, while AT blocked the increase in PCAF. AT markedly improved cardiac remodeling in mice after MI by reducing endoplasmic reticulum stress (ERS). In vivo, similar to AT, pharmacological inhibition of PCAF by Embelin improved cardiac recovery and attenuated ERS in MI mice. Furthermore, we observed that both IGF-1, a simulated exercise environment, and Embelin protected from H2O2-induced cardiomyocyte injury, while PCAF overexpression by viruses or the sirtuin inhibitor nicotinamide eliminated the protective effect of IGF-1 in H9C2 cells. Thus, our data indicate that maintaining low PCAF levels plays an essential role in AT-mediated cardiac protection, and PCAF inhibition represents a promising therapeutic target for attenuating cardiac remodeling after MI.

Who Transmits Tuberculosis to Whom: A Cross-Sectional Analysis of a Cohort Study in Lima, Peru.

RATIONALE: The persistent burden of TB disease emphasizes the need to identify individuals with TB for treatment and those at a high risk of incident TB for prevention. Targeting interventions towards those at high risk of developing and transmitting tuberculosis is a public health priority. OBJECTIVES: We aimed to identify characteristics of individuals involved in tuberculosis transmission in a community setting, which may guide the prioritization of targeted interventions. METHODS: We collected clinical and socio-demographic data from a cohort of tuberculosis patients in Lima, Peru. We used whole-genome sequencing data to assess the genetic distance between all possible pairs of patients; we considered pairs to be the result of a direct transmission event if they differed by three or fewer SNPs and we assumed that the first diagnosed patient in a pair was the transmitter and the second to be the recipient. We used logistic regression to examine the association between host factors and the likelihood of direct tuberculosis transmission. MAIN RESULTS: Analyzing data from 2,518 tuberculosis index patients, we identified 1,447 direct transmission pairs. Regardless of recipient attributes, individuals less than 34 years old, males, and those with a history of incarceration had a higher likelihood of being transmitters in direct transmission pairs. Direct transmission was more likely when both patients were drinkers or smokers. CONCLUSIONS: This study identifies men, young adults, former prisoners, alcohol consumers, and smokers as priority groups for targeted interventions. Innovative strategies are needed to extend tuberculosis screening to social groups like young adults and prisoners with limited access to routine preventive care. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Parallelized gene cluster editing illuminates mechanisms of epoxyketone proteasome inhibitor biosynthesis.

Advances in DNA sequencing technology and bioinformatics have revealed the enormous potential of microbes to produce structurally complex specialized metabolites with diverse uses in medicine and agriculture. However, these molecules typically require structural modification to optimize them for application, which can be difficult using synthetic chemistry. Bioengineering offers a complementary approach to structural modification but is often hampered by genetic intractability and requires a thorough understanding of biosynthetic gene function. Expression of specialized metabolite biosynthetic gene clusters (BGCs) in heterologous hosts can surmount these problems. However, current approaches to BGC cloning and manipulation are inefficient, lack fidelity, and can be prohibitively expensive. Here, we report a yeast-based platform that exploits transformation-associated recombination (TAR) for high efficiency capture and parallelized manipulation of BGCs. As a proof of concept, we clone, heterologously express and genetically analyze BGCs for the structurally related nonribosomal peptides eponemycin and TMC-86A, clarifying remaining ambiguities in the biosynthesis of these important proteasome inhibitors. Our results show that the eponemycin BGC also directs the production of TMC-86A and reveal contrasting mechanisms for initiating the assembly of these two metabolites. Moreover, our data shed light on the mechanisms for biosynthesis and incorporation of 4,5-dehydro-l-leucine (dhL), an unusual nonproteinogenic amino acid incorporated into both TMC-86A and eponemycin.

Spatial scale of tuberculosis transmission in Lima, Peru.

Spatially targeted interventions may be effective alternatives to individual or population-based prevention strategies against tuberculosis (TB). However, their efficacy may depend on the mechanisms that lead to geographically constrained hotspots. Local TB incidence may reflect high levels of local transmission; conversely, they may point to frequent travel of community members to high-risk areas. We used whole-genome sequencing to explore patterns of TB incidence and transmission in Lima, Peru. Between 2009 and 2012, we recruited incident pulmonary TB patients and their household contacts, whom we followed for the occurrence of TB disease. We used whole-genome sequences of 2,712 Mycobacterial tuberculosis isolates from 2,440 patients to estimate pariwise genomic distances and compared these to the spatial distance between patients' residences. Genomic distances increased rapidly as spatial distances increased and remained high beyond 2 km of separation. Next, we divided the study catchment area into 1 × 1 km grid-cell surface units and used household spatial coordinates to locate each TB patient to a specific cell. We estimated cell-specific transmission by calculating the proportion of patients in each cell with a pairwise genomic distance of 10 or fewer single-nucleotide polymorphisms. We found that cell-specific TB incidence and local transmission varied widely but that cell-specific TB incidence did not correlate closely with our estimates of local transmission (Cohen's k = 0.27). These findings indicate that an understanding of the spatial heterogeneity in the relative proportion of TB due to local transmission may help guide the implementation of spatially targeted interventions.

Chest Radiograph Screening for Detecting Subclinical Tuberculosis in Asymptomatic Household Contacts, Peru.

The World Health Organization's end TB strategy promotes the use of symptom and chest radiograph screening for tuberculosis (TB) disease. However, asymptomatic early states of TB beyond latent TB infection and active disease can go unrecognized using current screening criteria. We conducted a longitudinal cohort study enrolling household contacts initially free of TB disease and followed them for the occurrence of incident TB over 1 year. Among 1,747 screened contacts, 27 (52%) of the 52 persons in whom TB subsequently developed during follow-up had a baseline abnormal radiograph. Of contacts without TB symptoms, persons with an abnormal radiograph were at higher risk for subsequent TB than persons with an unremarkable radiograph (adjusted hazard ratio 15.62 [95% CI 7.74-31.54]). In young adults, we found a strong linear relationship between radiograph severity and time to TB diagnosis. Our findings suggest chest radiograph screening can extend to detecting early TB states, thereby enabling timely intervention.

USP18 induction regulates immunometabolism to attenuate M1 signal-polarized macrophages and enhance IL-4-polarized macrophages in systemic lupus erythematosus.

Effective treatment of systemic lupus erythematosus (SLE) remains an unmet need. Different subsets of macrophages play differential roles in SLE and the modulation of macrophage polarization away from M1 status is beneficial for SLE therapeutics. Given the pathogenic roles of type I interferons (IFN-I) in SLE, this study investigated the effects and mechanisms of a mitochondria localization molecule ubiquitin specific peptidase 18 (USP18) preserving anti-IFN effects and isopeptidase activity on macrophage polarization. After observing USP18 induction in monocytes from SLE patients, we studied mouse bone marrow-derived macrophages and showed that USP18 deficiency increased M1signal (LPS + IFN-γ treatment)-induced macrophage polarization, and the effects involved the induction of glycolysis and mitochondrial respiration and the expression of several glycolysis-associated enzymes and molecules, such as hypoxia-inducible factor-1α. Moreover, the effects on mitochondrial activities, such as mitochondrial DNA release and mitochondrial reactive oxygen species production were observed. In contrast, the overexpression of USP18 inhibited M1signal-mediated and enhanced interleukin-4 (IL-4)-mediated polarization of macrophages and the related cellular events. Moreover, the levels of USP18 mRNA expression showed tendency of correlation with the expression of metabolic enzymes in monocytes from patients with SLE. We thus concluded that by preserving anti-IFN effect and downregulating M1 signaling, promoting USP18 activity may serve as a useful approach for SLE therapeutics.

Arginine-linked HPV-associated E7 displaying bacteria-derived outer membrane vesicles as a potent antigen-specific cancer vaccine.

BACKGROUND: Bacteria-based cancer therapy have demonstrated innovative strategies to combat tumors. Recent studies have focused on gram-negative bacterial outer membrane vesicles (OMVs) as a novel cancer immunotherapy strategy due to its intrinsic properties as a versatile carrier. METHOD: Here, we developed an Human Papillomavirus (HPV)-associated E7 antigen displaying Salmonella-derived OMV vaccine, utilizing a Poly(L-arginine) cell penetrating peptide (CPP) to enhance HPV16 E7 (aa49-67) H-2 Db and OMV affinity, termed SOMV-9RE7. RESULTS: Due to OMV's intrinsic immunogenic properties, SOMV-9RE7 effectively activates adaptive immunity through antigen-presenting cell uptake and antigen cross-presentation. Vaccination of engineered OMVs shows immediate tumor suppression and recruitment of infiltrating tumor-reactive immune cells. CONCLUSION: The simplicity of the arginine coating strategy boasts the versatility of immuno-stimulating OMVs that can be broadly implemented to personalized bacterial immunotherapeutic applications.

Associating Knee Osteoarthritis Progression with Temporal-Regional Graph Convolutional Network Analysis on MR Images.

BACKGROUND: Artificial intelligence shows promise in assessing knee osteoarthritis (OA) progression on MR images, but faces challenges in accuracy and interpretability. PURPOSE: To introduce a temporal-regional graph convolutional network (TRGCN) on MR images to study the association between knee OA progression status and network outcome. STUDY TYPE: Retrospective. POPULATION: 194 OA progressors (mean age, 62 ± 9 years) and 406 controls (mean age, 61 ± 9 years) from the OA Initiative were randomly divided into training (80%) and testing (20%) cohorts. FIELD STRENGTH/SEQUENCE: Sagittal 2D IW-TSE-FS (IW) and 3D-DESS-WE (DESS) at 3T. ASSESSMENT: Anatomical subregions of cartilage, subchondral bone, meniscus, and the infrapatellar fat pad at baseline, 12-month, and 24-month were automatically segmented and served as inputs to form compartment-based graphs for a TRGCN model, which containing both regional and temporal information. The performance of models based on (i) clinical variables alone, (ii) radiologist score alone, (iii) combined features (containing i and ii), (iv) composite TRGCN (combining TRGCN, i and ii), (v) radiomics features, (vi) convolutional neural network based on Densenet-169 were compared. STATISTICAL TESTS: DeLong test was performed to compare the areas under the ROC curve (AUC) of all models. Additionally, interpretability analysis was done to evaluate the contributions of individual regions. A P value <0.05 was considered significant. RESULTS: The composite TRGCN outperformed all other models with AUCs of 0.841 (DESS) and 0.856 (IW) in the testing cohort (all P < 0.05). Interpretability analysis highlighted cartilage's importance over other structures (42%-45%), tibiofemoral joint's (TFJ) dominance over patellofemoral joint (PFJ) (58%-67% vs. 12%-37%), and importance scores changes in compartments over time (TFJ vs. PFJ: baseline: 44% vs. 43%, 12-month: 52% vs. 39%, 24-month: 31% vs. 48%). DATA CONCLUSION: The composite TRGCN, capturing temporal and regional information, demonstrated superior discriminative ability compared with other methods, providing interpretable insights for identifying knee OA progression. TECHNICAL EFFICACY: Stage 2.

Elucidating the transport of water and ions in the nanochannel of covalent organic frameworks by molecular dynamics.

Inspired by biological channels, achieving precise separation of ion/water and ion/ion requires finely tuned pore sizes at molecular dimensions and deliberate exposure of charged groups. Covalent organic frameworks (COFs), a class of porous crystalline materials, offer well-defined nanoscale pores and diverse structures, making them excellent candidates for nanofluidic channels that facilitate ion and water transport. In this study, we perform molecular simulations to investigate the structure and kinetics of water and ions confined within the typical COFs with varied exposure of charged groups. The COFs exhibit vertically arrayed nanochannels, enabling diffusion coefficients of water molecules within COFs to remain within the same order of magnitude as in the bulk. The motion of water molecules manifests in two distinct modes, creating a mobile hydration layer around acid groups. The ion diffusion within COFs displays a notable disparity between monovalent (M+) and divalent (M2+) cations. As a result, the selectivity of M+/M2+ can exceed 100, while differentiation among M+ is less pronounced. In addition, our simulations indicate a high rejection (R > 98%) in COFs, indicating their potential as ideal materials for desalination. The chemical flexibility of COFs indicates that would hold significant promise as candidates for advanced artificial ion channels and separation membranes.

The DEAD-box helicase Hlc regulates basal transcription and chromatin opening of stress-responsive genes.

Stress-responsive genes are lowly transcribed under normal conditions and robustly induced in response to stress. The significant difference between basal and induced transcription indicates that the general transcriptional machinery requires a mechanism to distinguish each transcription state. However, what factors specifically function in basal transcription remains poorly understood. Using a classic model stress-responsive gene (Drosophila MtnA), we found that knockdown of the DEAD-box helicase Hlc resulted in a significant transcription attenuation of MtnA under normal, but not stressed, conditions. Mechanistically, Hlc directly binds to the MtnA locus to maintain the accessibility of chromatin near the transcriptional start site, which allows the recruitment of RNA polymerase II and subsequent MtnA transcription. Using RNA-seq, we then identified plenty of additional stress-responsive genes whose basal transcription was reduced upon knockdown of Hlc. Taken together, these data suggest that Hlc-mediated basal transcription regulation is an essential and widespread mechanism for precise control of stress-responsive genes.

eIF3j inhibits translation of a subset of circular RNAs in eukaryotic cells.

Increasing studies have revealed that a subset of circular RNAs (circRNAs) harbor an open reading frame and can act as protein-coding templates to generate functional proteins that are closely associated with multiple physiological and disease-relevant processes, and thus proper regulation of synthesis of these circRNA-derived proteins is a fundamental cellular process required for homeostasis maintenance. However, how circRNA translation initiation is coordinated by different trans-acting factors remains poorly understood. In particular, the impact of different eukaryotic translation initiation factors (eIFs) on circRNA translation and the physiological relevance of this distinct regulation have not yet been characterized. In this study, we screened all 43 Drosophila eIFs and revealed the conflicting functions of eIF3 subunits in the translational control of the translatable circRNA circSfl: eIF3 is indispensable for circSfl translation, while the eIF3-associated factor eIF3j is the most potent inhibitor. Mechanistically, the binding of eIF3j to circSfl promotes the disassociation of eIF3. The C-terminus of eIF3j and an RNA regulon within the circSfl untranslated region (UTR) are essential for the inhibitory effect of eIF3j. Moreover, we revealed the physiological relevance of eIF3j-mediated circSfl translation repression in response to heat shock. Finally, additional translatable circRNAs were identified to be similarly regulated in an eIF3j-dependent manner. Altogether, our study provides a significant insight into the field of cap-independent translational regulation and undiscovered functions of eIF3.

Epidemiological Predictors of Financial Toxicity in Surgical Burn Injuries: A Multicenter, Longitudinal, Cohort Study.

BACKGROUND: Burns constitute a major global health challenge, causing over 11 million injuries and 300,000 deaths annually and surpassing the economic burden of cervical cancer and HIV combined. Despite this, patient-level financial consequences of burn injuries remain poorly quantified, with a significant gap in data from low- and middle-income countries. In this study, we evaluate financial toxicity in burn patients. METHODS: A prospective, multicenter cohort study was conducted across two tertiary care hospitals in India, assessing 123 adult surgical in-patients undergoing operative interventions for burn injuries. Patient sociodemographic, clinical, and financial data were collected through surveys and electronic records during hospitalization and at 1, 3, and 6 months postoperatively. Out-of-pocket costs (OOPCs) for surgical burn treatment were evaluated during hospitalization. Longitudinal changes in income, employment status, and affordability of basic subsistence needs were assessed at the 1-, 3-, and 6-month postoperative time point. Degree of financial toxicity was calculated using a combination of the metrics catastrophic health expenditure and financial hardship. Development of financial toxicity was compared by sociodemographic and clinical characteristics using logistic regression models. RESULTS: Of the cohort, 60% experienced financial toxicity. Median OOPCs was US$555.32 with the majority of OOPCs stemming from direct nonmedical costs (US$318.45). Cost of initial hospitalization exceeded monthly annual income by 80%. Following surgical burn care, income decreased by US$318.18 within 6 months, accompanied by a 53% increase in unemployment rates. At least 40% of the cohort consistently reported inability to afford basic subsistence needs within the 6-month perioperative period. Significant predictors of developing financial toxicity included male gender (odds ratio, 4.17; 95% confidence interval, 1.25-14.29; P = 0.02) and hospital stays exceeding 20 days (odds ratio, 11.17; 95% confidence interval, 2.11-59.22; P ≤ 0.01). CONCLUSIONS: Surgical treatment for burn injuries is associated with substantial financial toxicity. National and local policies must expand their scope beyond direct medical costs to address direct nonmedical and indirect costs. These include burn care insurance, teleconsultation follow-ups, hospital-affiliated subsidized lodging, and resources for occupational support and rehabilitation. These measures are crucial to alleviate the financial burden of burn care, particularly during the perioperative period.

Utility of Mycobacterium tuberculosis genome sequencing snapshots to assess transmission dynamics over time.

We explored the utility of brief Mycobacterium tuberculosis whole-genome sequencing (WGS) "snapshots" at a sentinel site within Lima, Peru for evaluating local transmission dynamics over time. Within a 17 km2 area, 15/70 (21%) isolates with WGS collected during 2011-2012 and 22/81 (27%) collected during 2020-2021 were clustered (p = 0.414), and additional isolates clustered with those from outside the area. Isolates from the later period were disproportionately related to large historic clusters in Lima from the earlier period. WGS snapshots at a sentinel site may not be useful for monitoring transmission, but monitoring the persistence of large transmission clusters might be.

Time interval between hCG administration and oocyte retrieval and ART outcomes: an updated systematic review and meta-analysis.

RESEARCH QUESTION: To explore whether prolonged hCG-ovum pickup interval improves assisted reproductive technology outcomes. DESIGN: CENTRAL, CNKI, Cochrane Systematic Reviews, EMBASE, MEDLINE, PUBMED, and Web of Science up to May 13 2023 were searched for studies reporting associations between hCG-ovum pickup intervals and assisted reproductive technology outcomes. Intervention types included short (≤ 36 h) and long (> 36 h) hCG-ovum pickup intervals in assisted reproductive technology cycles. All outcomes were based upon only fresh embryo transfers. Primary outcome is defined as the clinical pregnancy rate. Data were pooled using random-effects models. Heterogeneity was assessed using the I 2 statistics. RESULTS: Twelve studies were included in the meta-analysis, including five retrospective cohort studies, one prospective cohort study, and six randomized or quasi-randomized controlled trials. The short and long interval groups had similar oocyte maturation rates, fertilization rate and high-quality embryo rate (OR, 0.69; 95% CI, 0.45-1.06; I 2 = 91.1%, OR, 0.88; 95% CI, 0.77-1.0; I 2 = 44.4% and OR, 1.05; 95% CI, 0.95-1.17; I 2 = 8.6%, respectively). The clinical pregnancy rates in the long retrieval group were significantly higher than in the short retrieval group (OR, 0.66; 95% CI, 0.45-0.95; I 2 = 35.4%). The groups had similar miscarriage and live birth rates (OR, 1.92; 95% CI, 0.66-5.60; I 2 = 0.0% and OR, 0.50; 95% CI, 0.24-1.04; I 2 = 0.0%, respectively). CONCLUSIONS: The clinical pregnancy rates can be increased by prolonging the hCG-ovum pickup interval, which would help us develop more reasonable time schedules for fertility centers and patients. META-ANALYSIS REGISTRATION: PROSPERO CRD42022310006 (28 Apr 2022).