High-throughput printing of combinatorial materials from aerosols.

The development of new materials and their compositional and microstructural optimization are essential in regard to next-generation technologies such as clean energy and environmental sustainability. However, materials discovery and optimization have been a frustratingly slow process. The Edisonian trial-and-error process is time consuming and resource inefficient, particularly when contrasted with vast materials design spaces1. Whereas traditional combinatorial deposition methods can generate material libraries2,3, these suffer from limited material options and inability to leverage major breakthroughs in nanomaterial synthesis. Here we report a high-throughput combinatorial printing method capable of fabricating materials with compositional gradients at microscale spatial resolution. In situ mixing and printing in the aerosol phase allows instantaneous tuning of the mixing ratio of a broad range of materials on the fly, which is an important feature unobtainable in conventional multimaterials printing using feedstocks in liquid-liquid or solid-solid phases4-6. We demonstrate a variety of high-throughput printing strategies and applications in combinatorial doping, functional grading and chemical reaction, enabling materials exploration of doped chalcogenides and compositionally graded materials with gradient properties. The ability to combine the top-down design freedom of additive manufacturing with bottom-up control over local material compositions promises the development of compositionally complex materials inaccessible via conventional manufacturing approaches.

Multilocus Distance-Regulated Sensor Array for Recognition of Polyphenols via Machine Learning and Indicator Displacement Assay.

Developing new strategies to construct sensor arrays that can effectively distinguish multiple natural components with similar structures in mixtures is an exceptionally challenging task. Here, we propose a new multilocus distance-modulated indicator displacement assay (IDA) strategy for constructing a sensor array, incorporating machine learning optimization to identify polyphenols. An 8-element array, comprising two fluorophores and their six dynamic covalent complexes (C1-C6) formed by pairing two fluorophores with three distinct distance-regulated quenchers, has been constructed. Polyphenols with diverse spatial arrangements and combinatorial forms compete with the fluorophores by forming pseudocycles with quenchers within the complexes, leading to varying degrees of fluorescence recovery. The array accurately and effectively distinguished four tea polyphenols and 16 tea varieties, thereby demonstrating the broad applicability of the multilocus distance-modulated IDA array in detecting polyhydroxy foods and natural medicines.

Hybrid Printing of Fully Integrated Microfluidic Devices for Biosensing.

The advent of 3D printing has facilitated the rapid fabrication of microfluidic devices that are accessible and cost-effective. However, it remains a challenge to fabricate sophisticated microfluidic devices with integrated structural and functional components due to limited material options of existing printing methods and their stringent requirement on feedstock material properties. Here, a multi-materials multi-scale hybrid printing method that enables seamless integration of a broad range of structural and functional materials into complex devices is reported. A fully printed and assembly-free microfluidic biosensor with embedded fluidic channels and functionalized electrodes at sub-100 µm spatial resolution for the amperometric sensing of lactate in sweat is demonstrated. The sensors present a sensitive response with a limit of detection of 442 nm and a linear dynamic range of 1-10 mm, which are performance characteristics relevant to physiological levels of lactate in sweat. The versatile hybrid printing method offers a new pathway toward facile fabrication of next-generation integrated devices for broad applications in point-of-care health monitoring and sensing.

The role of sialidase Neu1 in respiratory diseases.

Neu1 is a sialidase enzyme that plays a crucial role in the regulation of glycosylation in a variety of cellular processes, including cellular signaling and inflammation. In recent years, numerous evidence has suggested that human NEU1 is also involved in the pathogenesis of various respiratory diseases, including lung infection, chronic obstructive pulmonary disease (COPD), asthma, and pulmonary fibrosis. This review paper aims to provide an overview of the current research on human NEU1 and respiratory diseases.

Insights into tolerance mechanisms of earthworms (Eisenia fetida) in copper-contaminated soils by integrating multi-omics analyses.

Earthworms can resist high levels of soil copper (Cu) contamination and play an essential role in absorbing them effectively. However, the molecular mechanisms underlying Cu tolerance in earthworms are poorly understood. To address this research gap, we studied alterations of Eisenia fetida in antioxidant enzymes, gut microbiota, metabolites, and genes under varying levels of Cu exposure soils (0, 67.58, 168.96, 337.92 mg/kg). Our results revealed a reduction in antioxidant enzyme activities across all treatment groups, indicating an adaptive response to alleviate Cu-induced oxidative stress. Analysis of gut microbiota revealed a significant increase in the abundance of bacteria associated with nutrient uptake and Cu2+ excretion under Cu stress. Furthermore, metabolomic analysis discovered an increase in certain metabolites associated with energy metabolism, such as pyruvic acid, L-malic acid, and fumaric acid, as Cu concentration escalated. These results suggested that enhanced energy supply contributes to the elevated tolerance of E. fetida towards Cu. Additionally, transcriptome analysis not only identified crucial detoxification genes (Hsp70, CTSL, GST, CHAC, and GCLC), but also confirmed the critical role of glutathione metabolism as a key pathway in E. fetida Cu detoxification processes. These findings provide a new perspective on the molecular mechanisms of Cu tolerance in earthworms.

A Dual Fluorescence Turn-On Sensor Array Formed by Poly(para-aryleneethynylene) and Aggregation-Induced Emission Fluorophores for Sensitive Multiplexed Bacterial Recognition.

Bacterial infections have emerged as the leading causes of mortality and morbidity worldwide. Herein, we developed a dual-channel fluorescence "turn-on" sensor array, comprising six electrostatic complexes formed from one negatively charged poly(para-aryleneethynylene) (PPE) and six positively charged aggregation-induced emission (AIE) fluorophores. The 6-element array enabled the simultaneous identification of 20 bacteria (OD600=0.005) within 30s (99.0 % accuracy), demonstrating significant advantages over the array constituted by the 7 separate elements that constitute the complexes. Meanwhile, the array realized different mixing ratios and quantitative detection of prevalent bacteria associated with urinary tract infection (UTI). It also excelled in distinguishing six simulated bacteria samples in artificial urine. Remarkably, the limit of detection for E. coli and E. faecalis was notably low, at 0.000295 and 0.000329 (OD600), respectively. Finally, optimized by diverse machine learning algorithms, the designed array achieved 96.7 % accuracy in differentiating UTI clinical samples from healthy individuals using a random forest model, demonstrating the great potential for medical diagnostic applications.

Socioeconomic development shows positive links to the conservation efficiency of China's protected area network.

While the protected area (PA) covers >15% of the planet's terrestrial land area and continues to expand, factors determining its effectiveness in conserving endangered species are being debated. We investigated the links between direct anthropogenic pressures, socioeconomic settings, and the coverage of vertebrate taxa by China's PA network, and indicated that high socioeconomic status and low levels of human pressure correlate with high species coverage, with threatened mammals more effectively conserved than reptiles or amphibians. Positive links between conservation outcomes and socioeconomic progress appear linked to local livelihood improvements triggering positive perceptions of local PAs-aided further by ecological compensation and tourism schemes introduced in wealthy areas and reinforced by continued positive conservation outcomes. Socioeconomic development of China's less developed regions might assist regional PA efficiency and achievement of the Kunming-Montreal Global Biodiversity Framework, while also addressing potential shortcomings from an insufficient past focus on socioeconomic impacts for biodiversity conservation.

Challenges in αCD38-chimeric antigen receptor (CAR)-expressing natural killer (NK) cell-based immunotherapy in multiple myeloma: Harnessing the CD38dim phenotype of cytokine-stimulated NK cells as a strategy to prevent fratricide.

BACKGROUND AIMS: Adoptive cell therapy with chimeric antigen receptor (CAR)-expressing natural killer (NK) cells is an emerging approach that holds promise in multiple myeloma (MM). However, the generation of CAR-NK cells targeting CD38 is met with obstacles due to the expression of CD38 on NK cells. Knock-out of CD38 is currently explored as a strategy, although the consequences of the lack of CD38 expression with regards to engraftment and activity in the bone marrow microenvironment are not fully elucidated. Here, we present an alternative approach by harnessing the CD38dim phenotype occurring during long-term cytokine stimulation of primary NK cells. METHODS: Primary NK cells were expanded from peripheral blood mononuclear cells by long-term IL-2 stimulation. During expansion, the CD38 expression was monitored in order to identify a time point when introduction of a novel affinity-optimized αCD38-CAR confered optimal viability, i.e. prevented fratricide. CD38dim NK cells were trasduced with retroviral vectors encoding for the CAR trasngene and their functionality was assessed in in vitro activation and cytotoxicity assays. RESULTS: We verified the functionality of the αCD38-CAR-NK cells against CD38+ cell lines and primary MM cells. Importantly, we demonstrated that αCD38-CAR-NK cells derived from patients with MM have increased activity against autologous MM samples ex vivo. CONCLUSIONS: Overall, our results highlight that incorporation of a functional αCD38-CAR construct into a suitable NK-cell expansion and activation protocol results in a potent and feasible immunotherapeutic strategy for the treatment of patients with MM.

Printing thermoelectric inks toward next-generation energy and thermal devices.

The ability of thermoelectric (TE) materials to convert thermal energy to electricity and vice versa highlights them as a promising candidate for sustainable energy applications. Despite considerable increases in the figure of merit zT of thermoelectric materials in the past two decades, there is still a prominent need to develop scalable synthesis and flexible manufacturing processes to convert high-efficiency materials into high-performance devices. Scalable printing techniques provide a versatile solution to not only fabricate both inorganic and organic TE materials with fine control over the compositions and microstructures, but also manufacture thermoelectric devices with optimized geometric and structural designs that lead to improved efficiency and system-level performances. In this review, we aim to provide a comprehensive framework of printing thermoelectric materials and devices by including recent breakthroughs and relevant discussions on TE materials chemistry, ink formulation, flexible or conformable device design, and processing strategies, with an emphasis on additive manufacturing techniques. In addition, we review recent innovations in the flexible, conformal, and stretchable device architectures and highlight state-of-the-art applications of these TE devices in energy harvesting and thermal management. Perspectives of emerging research opportunities and future directions are also discussed. While this review centers on thermoelectrics, the fundamental ink chemistry and printing processes possess the potential for applications to a broad range of energy, thermal and electronic devices.

Safety and Immunogenicity of SARS-CoV-2 Vaccines in Patients With Chronic Liver Diseases (CHESS-NMCID 2101): A Multicenter Study.

BACKGROUND & AIMS: We aimed to assess the safety and immunogenicity of inactivated whole-virion severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in patients with chronic liver diseases (CLD) in this study. METHODS: This was a prospective, multi-center, open-label study. Participants aged over 18 years with confirmed CLD and healthy volunteers were enrolled. All participants received 2 doses of inactivated whole-virion SARS-CoV-2 vaccines. Adverse reactions were recorded within 14 days after any dose of SARS-CoV-2 vaccine, laboratory testing results were collected after the second dose, and serum samples of enrolled subjects were collected and tested for SARS-CoV-2 neutralizing antibodies at least 14 days after the second dose. RESULTS: A total of 581 participants (437 patients with CLD and 144 healthy volunteers) were enrolled from 15 sites in China. Most adverse reactions were mild and transient, and injection site pain (n = 36; 8.2%) was the most frequently reported adverse event. Three participants had grade 3 aminopherase elevation (defined as alanine aminopherase >5 upper limits of normal) after the second dose of inactivated whole-virion SARS-CoV-2 vaccination, and only 1 of them was judged as severe adverse event potentially related to SARS-CoV-2 vaccination. The positive rates of SARS-CoV-2 neutralizing antibodies were 76.8% in the noncirrhotic CLD group, 78.9% in the compensated cirrhotic group, 76.7% in the decompensated cirrhotic group (P = .894 among CLD subgroups), and 90.3% in healthy controls (P = .008 vs CLD group). CONCLUSION: Inactivated whole-virion SARS-CoV-2 vaccines are safe in patients with CLD. Patients with CLD had lower immunologic response to SARS-CoV-2 vaccines than healthy population. The immunogenicity is similarly low in noncirrhotic CLD, compensated cirrhosis, and decompensated cirrhosis.

Optimal encephalitis/meningitis roadmap via precise diagnosis and treatment (IMPROVE): a study protocol for a randomized controlled trial.

BACKGROUND: Encephalitis/meningitis brings a heavy disease burden, and the origin of disease remains unknown in 30-40% of patients. It is greatly significant that combinations of nucleic acid amplification and autoimmune antibody testing improves the diagnosis and treatment of encephalitis/meningitis. Moreover, though several diagnostic methods are in clinical use, a recognized and unified diagnosis and treatment process for encephalitis management remains unclear. METHODS: IMPROVE is a multicenter, open label, randomized controlled clinical trial that aims to evaluate the diagnostic performance, applications, and impact on patient outcomes of a new diagnostic algorithm that combines metagenomic next-generation sequencing (mNGS), multiplex polymerase chain reaction (PCR) and autoimmune antibody testing. The enrolled patients will be grouped into two parallel groups, multiplex PCR test plus autoimmune antibody group (Group I) or the mNGS plus autoimmune antibody group (Group II) with a patient ratio of 1:1. Both groups will be followed up for 12 months. The primary outcomes include the initial time of targeted treatment and the modified Rankin scale score on the 30th day of the trial. The secondary outcomes are the cerebrospinal fluid index remission rate on the 14th day, mortality rate on the 30th day, and an evaluation of diagnostic efficacy. The two groups are predicted to comprise of 484 people in total. DISCUSSION: To optimize the roadmap of encephalitis/meningitis, precise diagnosis, and treatment are of great significance. The effect of rapid diagnosis undoubtedly depends on the progression of new diagnostic tests, such as the new multiplex PCR, mNGS, and examination of broad-spectrum autoimmune encephalitis antibodies. This randomized-controlled study could allow us to obtain an accurate atlas of the precise diagnostic ability of these tests and their effect on the treatment and prognosis of patients. Trial registration ClinicalTrial.gov, NCT04946682. Registered 29 June 2021, 'Retrospectively registered', https://clinicaltrials.gov/ct2/show/NCT04946682?term=NCT04946682&draw=2&rank=1.

Evaluation of droplet digital PCR rapid detection method and precise diagnosis and treatment for suspected sepsis (PROGRESS): a study protocol for a multi-center pragmatic randomized controlled trial.

BACKGROUND: Sepsis is still a major public health concern and a medical emergency due to its high morbidity and mortality. Accurate and timely etiology diagnosis is crucial for sepsis management. As an emerging rapid and sensitive pathogen detection tool, digital droplet PCR (ddPCR) has shown promising potential in rapid identification of pathogens and antimicrobial resistance genes. However, the diagnostic value and clinical impact of ddPCR tests remains to be studied in patients with suspected sepsis. PROGRESS trial is aimed to evaluate the clinical effectiveness of a novel ddPCR assay compared with standard practice. METHODS: PROGRESS is a multicenter, open-label, pragmatic randomized controlled trial (pRCT) set in ten hospitals, including departments of infectious disease and intensive care units. In this study, a total of 2292 patients with suspected sepsis will be randomly assigned to two arms: the ddPCR group and the control group with a ratio of 3:1. The primary outcome is the diagnostic efficacy, that is, the sensitivity and specificity of the ddPCR assay compared with the synchronous blood culture. Secondary outcomes include the mortality rates and the mean Sequential Organ Failure Assessment (SOFA) score at follow-up time points, the length of stay in the hospital, the time to directed antimicrobial therapy, duration of broad-spectrum antibiotic use, and the EQ-5D-5L score on day 90. DISCUSSION: It is the first multicenter pragmatic RCT to explore the diagnostic efficacy and clinical impact of the ddPCR assay in patients with suspected sepsis, taking advantage of both RCT's ability to establish causality and the feasibility of pragmatic approaches in real-world studies (RWS). This trial will help us to get a comprehensive view of the assay's capacity for precise diagnosis and treatment of sepsis. It has the potential to monitor the pathogen load change and to guide the antimicrobial therapy, making a beneficial impact on the prognosis of sepsis patients. TRIAL REGISTRATION: ClinicalTrial.gov, NCT05190861. Registered January 13, 2022-'Retrospectively registered', https://clinicaltrials.gov/ct2/show/NCT05190861 .

Integrated Analysis of lncRNAs and mRNAs Identifies a Potential Driver lncRNA FENDRR in Lung Cancer in Xuanwei, China.

This study was to screen out potential driver long non-coding RNAs (lncRNAs) in lung cancer in Xuanwei (LCXW) differently expressed mRNAs and lncRNAs were detected by gene expression microarrays in 23 paired lung adenocarcinoma and adjacent tissues. Combined bioinformatics analysis was performed to identify potential driver lncRNAs and their potential regulatory relationships. Transcriptome and clinical data in TCGA-LUAD were used as comparison and validation dataset. The comparison of LCXW and TCGA-LUAD revealed significant differences in expression of some genes, signaling pathways affected by differentially expressed genes, and the 5-year survival rate of patients. We identified 14 consistently deregulated mRNAs and 5 lncRNAs as candidate genes, which affected multiple cancer-related pathways and influenced patients' overall survival. By combined bioinformatics analysis, we further identified a potential driver lncRNA fetal-lethal non-coding developmental regulatory RNA (FENDRR) and proposed its possible regulation mechanism. The low expression of FENDRR was positively correlated with Krüppel-like factor4 (KLF4), KLF4 down-regulation may loss the activation function of cyclin-dependent kinase inhibitor 1A (CDKN1A) and cyclin-dependent kinase inhibitor 1C (CDKN1C) and the inhibition function of CyclinB1 (CCNB1), eventually cause excessive cell cycle activation and lead to lung cancer. This study revealed a potential FENDRR-KLF4-cell cycle regulation axis. These results lay an important foundation for further research on the pathogenesis of LCXW and identification of potential novel biomarkers or therapeutic targets.

Analysis of circular RNA expression profiles of lung cancer in Xuanwei, China.

BACKGROUND: Mounting evidence indicates that circular RNAs (circRNAs) could play a pivotal role in cancers. However, due to the lack of sensitive biomarkers, most lung cancer in Xuanwei (LCXW) patients are still diagnosed at an advanced stage accompany with distant metastasis. METHODS: According to the stage of LCXW patients and tissue sources, circRNAs microarray detection was carried out in six groups. Considering fold change, raw intensity, the length of circRNAs, and P-value, we selected eightcircRNAs for further study. A total of 50 paired LCXW tissues were carried out real-time quantitative polymerase chain reaction (RT-qPCR) in order to extended sample size to verify the expression of these circRNAs. RESULTS: We designed 13 617 human circRNA probes for the human circular RNA microarray, detected 10 819 circRNA in six groups of samples; 537 circRNAs were differentially expressed consistently in every stage. Through RT-qPCR, we selected 8 circRNAs, three of which were upregulated (hsa_circ_0005927, hsa_circ_0069397 and hsa_circ_0000937) and five were downregulated (hsa_circ_0001936, hsa_circ_0005255, hsa_circRNA_406010, hsa_circ_0007064, hsa_circ_0000907) in tumor tissues, only hsa_circ_0001936 showed the opposite expression between microarray and RT-qPCR, others were consistent. Additionally, hsa_circ_0005927 and hsa_circ_0001936 were significantly correlated with tumor size, and hsa_circRNA_406010 was related to the prognosis of LCXW patients. CONCLUSION: Together, these results suggest that hsa_circ_0005927, hsa_circ_0001936, and hsa_circRNA_406010 may serve as the novel potential biomarkers for LCXW. Moreover, these results may provide a new insight for the pathogenesis of LCXW.

Metabolite changes associated with earthworms (Eisenia fetida) graphene exposure revealed by matrix-assisted laser desorption/ionization mass spectrometry imaging.

The increased production and environmental release of graphene nanoparticles has raised concerns about its environmental impact, but the effects of graphene on living organisms at the metabolic level remain unknown. In this study, we used matrix assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI)-based untargeted metabolomics to investigate the metabolic response of juvenile earthworms (Eisenia fetida) to graphene exposure in soil tests for the first time. Our results reveal that graphene-exposure significantly disturbs earthworm metabolome, and graphene toxicity on earthworm shows non-concentration-dependent effect. Alanine, phenylalanine, proline, glutamate, arginine, histidine, maltose, glucose, malate, succinate, myo-inositol, and spermidine were successfully screened as significantly change compounds in earthworms for the exposure of graphene. The heterogeneous distributions of these metabolites in earthworm were also clearly imaged by MALDI-MSI. Our MSI results fully showed that the metabolite expression levels in juvenile earthworms significantly changed (up-/down-regulation) after exposure to graphene nanoparticles. This work improves our understanding of graphene nanoparticle toxicity to juvenile earthworms and also enables the continued progression of MALDI-MSI-based metabolomics as an emerging, reliable, and rapid ecotoxicological tool for assessing contaminant toxicity.

[Analysis of genomic copy number variations in two sisters with primary amenorrhea and hyperandrogenism].

OBJECTIVE: To analyze genomic copy number variations (CNVs) in two sisters with primary amenorrhea and hyperandrogenism. METHODS: G-banding was performed for karyotype analysis. The whole genome of the two sisters were scanned and analyzed by array-based comparative genomic hybridization (array-CGH). The results were confirmed with real-time quantitative PCR (RT-qPCR). RESULTS: No abnormality was found by conventional G-banded chromosome analysis. Array-CGH has identified 11 identical CNVs from the sisters which, however, overlapped with CNVs reported by the Database of Genomic Variants (http://projects.tcag.ca/variation/). Therefore, they are likely to be benign. In addition, a -8.44 Mb 9p11.1-p13.1 duplication (38,561,587-47,002,387 bp, hg18) and a -80.9 kb 4q13.2 deletion (70,183,990-70,264,889 bp, hg18) were also detected in the elder and younger sister, respectively. The relationship between such CNVs and primary amenorrhea and hyperandrogenism was however uncertain. RT-qPCR results were in accordance with array-CGH. CONCLUSION: Two CNVs were detected in two sisters by array-CGH, for which further studies are needed to clarify their correlation with primary amenorrhea and hyperandrogenism.

MicroRNA-212 inhibits osteosarcoma cells proliferation and invasion by down-regulation of Sox4.

BACKGROUND: Multiple MicroRNAs (miRNAs) have been identified in the development and progression of osteosarcoma. However, the expression and roles of miR-212 in osteosarcoma remain largely undefined. METHODS: Real-time PCR assays were used to detect the expression of miR-212 in human osteosarcoma tissues. MiR-212 mimics were introduced into MG63 and U2OS cells. Bioinformatic prediction was used to identify the potential targets of miR-212. Protein expression analysis, luciferase assays and rescue assays were used to confirm the substrate of miR-212. RESULTS: miR-212 was significantly down-regulated in human osteosarcoma tissues, compared with adjacent normal tissues. Introduction of miR-212 mimics into MG63 and U2OS cells inhibited cell proliferation and invasion. Besides, miR-212 overexpression could also inhibit tumor growth in the nude mice. Additionally, bioinformatic prediction suggested that the sex-determining region Y-box 4 (Sox4) is a target gene of miR-212. Sox4 inhibition phenocopied the roles of miR-212, while restored expression of Sox4 dampened miR-212-mediated suppression of tumor progression. CONCLUSION: The miR-212/Sox4 interaction plays an important role of in the osteosarcoma progression.

Exome sequencing identifies mutations in ABCD1 and DACH2 in two brothers with a distinct phenotype.

BACKGROUND: We report on two brothers with a distinct syndromic phenotype and explore the potential pathogenic cause. METHODS: Cytogenetic tests and exome sequencing were performed on the two brothers and their parents. Variants detected by exome sequencing were validated by Sanger sequencing. RESULTS: The main phenotype of the two brothers included congenital language disorder, growth retardation, intellectual disability, difficulty in standing and walking, and urinary and fecal incontinence. To the best of our knowledge, no similar phenotype has been reported previously. No abnormalities were detected by G-banding chromosome analysis or array comparative genomic hybridization. However, exome sequencing revealed novel mutations in the ATP-binding cassette, sub-family D member 1 (ABCD1) and Dachshund homolog 2 (DACH2) genes in both brothers. The ABCD1 mutation was a missense mutation c.1126G > C in exon 3 leading to a p.E376Q substitution. The DACH2 mutation was also a missense mutation c.1069A > T in exon 6, leading to a p.S357C substitution. The mother was an asymptomatic heterozygous carrier. Plasma levels of very-long-chain fatty acids were increased in both brothers, suggesting a diagnosis of adrenoleukodystrophy (ALD); however, their phenotype was not compatible with any reported forms of ALD. DACH2 plays an important role in the regulation of brain and limb development, suggesting that this mutation may be involved in the phenotype of the two brothers. CONCLUSION: The distinct phenotype demonstrated by these two brothers might represent a new form of ALD or a new syndrome. The combination of mutations in ABCD1 and DACH2 provides a plausible mechanism for this phenotype.

Longitudinal Analysis of Humoral and Cellular Immune Response up to 6 Months after SARS-CoV-2 BA.5/BF.7/XBB Breakthrough Infection and BA.5/BF.7-XBB Reinfection.

The rapid mutation of SARS-CoV-2 has led to multiple rounds of large-scale breakthrough infection and reinfection worldwide. However, the dynamic changes of humoral and cellular immunity responses to several subvariants after infection remain unclear. In our study, a 6-month longitudinal immune response evaluation was conducted on 118 sera and 50 PBMC samples from 49 healthy individuals who experienced BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection. By studying antibody response, memory B cell, and IFN-γ secreting CD4+/CD8+ T cell response to several SARS-CoV-2 variants, we observed that each component of immune response exhibited distinct kinetics. Either BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection induces relatively high level of binding and neutralizing antibody titers against Omicron subvariants at an early time point, which rapidly decreases over time. Most of the individuals at 6 months post-breakthrough infection completely lost their neutralizing activities against BQ.1.1, CH.1.1, BA.2.86, JN.1 and XBB subvariants. Individuals with BA.5/BF.7-XBB reinfection exhibit immune imprinting shifting and recall pre-existing BA.5/BF.7 neutralization antibodies. In the BA.5 breakthrough infection group, the frequency of BA.5 and XBB.1.16-RBD specific memory B cells, resting memory B cells, and intermediate memory B cells gradually increased over time. On the other hand, the frequency of IFN-γ secreting CD4+/CD8+ T cells induced by WT/BA.5/XBB.1.16 spike trimer remains stable over time. Overall, our research indicates that individuals with breakthrough infection have rapidly declining antibody levels but have a relatively stable cellular immunity that can provide some degree of protection from future exposure to new antigens.