Targeting the mammalian target of rapamycin pathway in neurological manifestations of Covid-19.

The diverse and severe nature of neurological manifestations associated with coronavirus disease 2019 (Covid-19) has garnered increasing attention. Exploring the potential to decrease neurological complications in Covid-19 patients involves targeting the mammalian target of rapamycin (mTOR) pathway as a therapeutic strategy. The mTOR pathway, widely recognised for its central role in essential cellular processes like synthesising proteins, facilitating autophagy, and modulating immune responses, has implications in various neurological disorders. Drawing parallels between these disorders and the observed neurological complications in Covid-19, we present a comprehensive review on the current understanding of mTOR signalling in the context of severe acute respiratory syndrome coronavirus 2 infection and neuroinflammation.

A nomogram for predicting neurogenic lower urinary tract dysfunction in patients with acute ischemic stroke: A retrospective study.

AIMS: To investigate the risk factors for neurogenic lower urinary tract dysfunction (NLUTD) in patients with acute ischemic stroke (AIS), and develop an internally validated predictive nomogram. The study aims to offer insights for preventing AIS-NLUTD. METHODS: We conducted a retrospective study on AIS patients in a Shenzhen Hospital from June 2021 to February 2023, categorizing them into non-NLUTD and NLUTD groups. The bivariate analysis identified factors for AIS-NLUTD (p < 0.05), integrated into a least absolute shrinkage and selection operator (LASSO) regression model. Significant variables from LASSO were used in a multivariate logistic regression for the predictive model, resulting in a nomogram. Nomogram performance and clinical utility were evaluated through receiver operating characteristic curves, calibration curves, decision curve analysis (DCA), and clinical impact curve (CIC). Internal validation used 1000 bootstrap resamplings. RESULTS: A total of 373 participants were included in this study, with an NLUTD incidence rate of 17.7% (66/373). NIHSS score (OR = 1.254), pneumonia (OR = 6.631), GLU (OR = 1.240), HGB (OR = 0.970), and hCRP (OR = 1.021) were used to construct a predictive model for NLUTD in AIS patients. The model exhibited good performance (AUC = 0.899, calibration curve p = 0.953). Internal validation of the model demonstrated strong discrimination and calibration abilities (AUC = 0.898). Results from DCA and CIC curves indicated that the prediction model had high clinical utility. CONCLUSIONS: We developed a predictive model for AIS-NLUTD and created a nomogram with strong predictive capabilities, assisting healthcare professionals in evaluating NLUTD risk among AIS patients and facilitating early intervention.

The Realities and Needs of Nursing Assistants Caring for Disabled Patients with Fecal Incontinence During Hospitalization: A Qualitative Study.

Objective: To explore the experience, role, and needs of medical nursing assistants during hospitalization in patients with incapacitated fecal incontinence. Methods: Qualitative study using reflexive thematic analysis. Semi-structured interviews were conducted with 21 medical nursing assistants from three hospitals in Southern China. Results: Four themes were constructed from the data: (1) Role perception. All participants described the multiple roles they played during care and knowledge and familiarity with the roles were seen as providing high-quality care to patients. (2) Career cognition. Overall, participants had a positive view of nurse assistants as a career. They believed that nursing experience was more important than training. (3) emotional belonging. The multiple roles of medical nursing assistants give them very mixed emotions. (4) Potential needs. Participants reported that the fatigue of repeatedly scrubbing and cleaning stools, the negative emotions that could not be faced and resolved, and their special status made them overwhelmed, potentially reflecting that they needed more support. Conclusions: This study highlights the roles, experiences, confusions, and needs of nursing assistants in caring for patients with disabling fecal incontinence. Suggested areas for improvement include the development of more intelligent fecal incontinence collection devices and the development of management and training strategies by health managers based on the specific context of medical nursing assistants to emphasize the role of medical nursing assistants and improve the quality of clinical care.

ß-Sheet Assembly Translates Conservative Single-Site Mutation into a Perturbation in Macroscopic Structure.

Transferring structural information from amino acid sequence to macroscale assembly is a challenging approach for designing protein quaternary structure. However, the pathway by which the slight variations in sequence result in a global perturbation effect on the assembled structure is unknown. Herein, we design two synthetic peptides, QNL-His and QNL-Arg, with one amino acid substitution and use scanning tunneling microscopy (STM) to image individual peptides in the assembled state. The submolecular resolution of STM enables us to determine the folding structure and ß-sheet supramolecular organization of peptides. QNL-His and QNL-Arg differ in their ß-strand length distribution in pleated ß-sheet association. These structural variations lead to distinguishable outcomes in their ß-sheet assembled fibrils and phase transitions. The comparison of QNL-His versus QNL-Arg structures and macroscopic properties unveils the role of assembly to amplify the structural variations associated with a single-site mutation from a single-molecule scale to a macroscopic scale.

Development and validation of a Decision-Making Ability Scale for postpartum urinary incontinence women engaging in pelvic floor physical therapy.

OBJECTIVE: This study aimed to develop and validate a Decision-Making Ability Scale (DMA-S) for postpartum urinary incontinence (PPUI) women engaging in pelvic floor physical therapy (PFPT). METHODS: Items were created in line with a review of the literature and exploratory qualitative study with 22 women. The items were submitted for expert opinion and a pilot implementation was made with 58 women with PPUI. Furthermore, the construct validity of the scale was tested with exploratory factor analysis (EFA) (n = 220) and confirmatory factor analysis (CFA) (n = 240). Internal consistency for the Chronbach's α and test-retest reliability for the intraclass correlation coefficient (ICC) were also investigated for the DMA-S in the study. RESULTS: The results of the EFA indicated a Kaiser-Meyer-Olkin value of 0.85 and Bartlett's test of sphericity showed a χ2 value of 8352.101, p < 0.001. After removing one item with factor loading values below 0.50, the resulting factor structure accounted for 83.38% of the total variance. The fit indices of the scale model tested in the CFA were determined as χ2 /df = 1.08 < 3, root mean square error of approximation = 0.018 < 0.08, comparative fit index = 0.996 > 0.90, Tucker-Lewis index = 0.995 > 0.90, goodness-of-fit index (GFI) = 0.933 > 0.90, adjusted GFI = 0.916 > 0.90, and incremental fit index = 0.996 > 0.90. The Cronbach's α values were 0.95-0.97 for the subdimensions of the scale and 0.93 for the total scale. Data also showed a good test-retest stability (ICC = 0.984). CONCLUSION: The DMA-S is a reliable and valid tool for assessing the decision-making ability for PPUI women engaging in PFPT.

Crystalline State Determines the Potency of Galectin-10 Protein Assembly to Induce Inflammation.

Protein crystallization is a prevalent phenomenon existing in the formation of intricate protein-assembled structures in living cells. Whether the crystallization of a protein would exert a specific biological function, however, remains poorly understood. Here, we reconstructed a recombinant galectin-10 (gal-10) protein and artificially engineered a gal-10 protein assembly in two distinguishable states: i.e., an insoluble crystalline state and a soluble state. The potency of the gal-10 protein in either the crystalline state or the soluble state to induce chemokine or cytokine release in the primary human nasal epithelial cells and nasal polyps derived from chronic rhinosinusitis patients with nasal polyps was investigated. The crystalline gal-10 upregulated the gene expression of chemokines or cytokines, including IL-1ß, IL-6, IL-8, TNF-α, and GM-CSF, in patient-derived primary cells and nasal polyps. In contrast, soluble gal-10 displayed a diminished potency to induce inflammation. Our results demonstrate that the gal-10 protein potency of activating inflammation is correlated with its crystalline state.

PEGylation of anti-MerTK Antibody Modulates Ocular Biodistribution.

Here, we explore whether PEGylation of antibodies can modulate their biodistribution to the eye, an organ once thought to be immune privileged but has recently been shown to be accessible to IV-administered large molecules, such as antibodies. We chose to PEGylate an anti-MerTK antibody, a target with known potential for ocular toxicity, to minimize biodistribution to retinal pigment epithelial cells (RPEs) in the eye by increasing the hydrodynamic volume of the antibody. We used site-specific conjugation to an engineered cysteine on anti-MerTK antibody to chemically attach 40-kDa branched or linear PEG polymers. Despite reduced binding to MerTK on cells, site-specifically PEGylated anti-MerTK retained similar potency in inhibiting MerTK-mediated macrophage efferocytosis of apoptotic cells. Importantly, we found that PEGylation of anti-MerTK significantly reduced MerTK receptor occupancy in RPE cells in both naïve mice and MC-38 tumor-bearing mice, with the branched PEG exhibiting a greater effect than linear PEG. Furthermore, similar to unconjugated anti-MerTK, PEGylated anti-MerTK antibody triggered type I IFN response and exhibited antitumor effect in syngeneic mouse tumor studies. Our results demonstrate the potential of PEGylation to control ocular biodistribution of antibodies.

Nanomicelles co-loading CXCR4 antagonist and doxorubicin combat the refractory acute myeloid leukemia.

Acute myeloid leukemia (AML) is featured with poor prognosis and high mortality, because chemo-resistance, nonspecific distribution and dose-limiting toxicity lead to a high rate of relapse and a very low 5-year survival percentage of less than 25%. CXCR4 is a highly expressed chemokine receptor in multiple types of AML cells and closely associated with the drug resistance and relapse. In this work, we integrate a chemically synthesized CXCR4 antagonistic peptide and doxorubicin using DSPE-mPEG2000 micelles (referred to as M-E5-Dox) that is applied to a very challenging refractory AML mouse model as well as human AML cell lines. Results showed that M-E5-Dox can effectively bind to the CXCR4-expressing AML cells, downregulating the signaling proteins mediated by CXCR4/CXCL12 axis and increasing the cellular uptake of Dox. Importantly, M-E5-Dox remarkably decreases the leukemic cells in the peripheral blood and bone marrow, as well as their infiltration in the spleen and liver of the AML mice, which in turn prolongs the survival significantly. Meanwhile, M-E5-Dox did not increase the cardiotoxicity of Dox. In conclusion, M-E5-Dox harnesses the functions of CXCR4 specific binding and CXCR4 antagonism of the peptide and the tumor cell killing capacity of Dox, which displays significant therapeutic effects and promising translational potentials for the treatment of refractory AML.

Composition-dependent multivalency of peptide-peptide interactions revealed by tryptophan-scanning mutagenesis.

We have examined in this contribution the composition dependence of binding characteristics in peptide-peptide interactions between an oligopeptide octa-glycine and a series of tryptophan-containing octapeptides. The binding energy associated with tryptophan-glycine interactions manifests pronounced stepwise binding characteristics as the number of tryptophan increases from 0 to 8 in the octapeptides consisting only of glycine and can be attributed to mono-, di-, and tri-valent peptide-peptide interactions. At the same time, only weak fluctuations in binding energy were observed as the number of tryptophan increases from 2 to 7. Such distinctive nonlinearity of composition-dependent tryptophan-glycine binding energy characteristics due to continuously varying tryptophan compositions in the octapeptides could be considered as a reflection of combinatorial contributions due to the hydrogen bonds originated from the indole moieties of tryptophan with the main chains of octapeptide of glycine containing N-H and C=O moieties and the van der Waals interactions (including π-π and π-CH interactions) between peptides.

Rare earth element lanthanum protects against atherosclerosis induced by high-fat diet via down-regulating MAPK and NF-κB pathways.

Rare earth elements, which are extensively used in environmental protection, medicine, food, aerospace and other fields, have attracted widespread attention in recent years. However, the effect on atherosclerosis and its biological mechanism remains unclear. To elucidate these problems, here we performed a study that Apolipoprotein E-deficient mice were fed with high-fat diet to promote the development of atherosclerosis, meanwhile, mice were received 0.1, 0.2, 1.0, 2.0 mg/kg lanthanum nitrate (La(NO3)3) for 12 weeks. The results showed that La(NO3)3 prominently inhibited aorta morphological alternations by histopathological examination. Meanwhile, La(NO3)3 regulated serum lipids, including reducing total cholesterol and increasing high-density lipoprotein. Moreover, the oxidative stress was alleviated by La(NO3)3 intervention through enhancing superoxide dismutase and glutathione, and decreasing malondialdehyde levels. In addition, enzyme-linked immunosorbent assay analysis showed La(NO3)3 could ameliorate the dysfunction of vascular endothelium with declined endothelin-1 and increased prostacyclin. Furthermore, Western blot analysis indicated that La(NO3)3 significantly down-regulated inflammation-mediated proteins including phosphorylated p38 mitogen-activated protein kinases (p-p38 MAPK), monocyte chemo-attractant protein, intercellular adhesion molecule-1, nuclear factor-kappa B p65 (NF-κB p65), tumor necrosis factor-α, interleukin-6 and interleukin-1ß, whereas up-regulated the inhibitor of NF-κB protein. In conclusion, La(NO3)3 ameliorates atherosclerosis by regulating lipid metabolism, oxidative stress, endothelial dysfunction and inflammatory response in mice. The potential mechanism associates with the inhibition of MAPK and NF-κB signaling pathways.

Position-coded multivalent peptide-peptide interactions revealed by tryptophan-scanning mutagenesis.

We demonstrate in this contribution the evidence that significant cooperative binding effect can be identified for the amino acid sites that are determinant to the binding characteristics in peptide-peptide interactions. The analysis of tryptophan-scanning mutagenesis of the 14-mer peptide consisting only of glycine provides a mapping of position-dependent contributions to the binding energy. The pronounced tryptophan-associated peptide-peptide interactions are originated from the indole moieties with the main chains of 14-mer glycines containing N-H and CO moieties. Specifically, with the presence of two tryptophans as determinant amino acids, cooperative binding can be observed, which are dependent on relative positions of the two tryptophans with a "volcano"-like characteristics. An optimal separation of 6-10 amino acids between two adjacent binding sites can be identified to achieve maximal binding interactions.

Steric Dependence of Chirality Effect in Surface-Mediated Peptide Assemblies Identified with Scanning Tunneling Microscopy.

Amino acid chirality has been recognized as an important driving force in constructing peptide architectures, via interactions such as chirality-induced stereochemical effect. The introduction of site-specific chiral conversion of l- and d-amino acids in peptide sequences could enable the pursuit of the chirality effects in peptide assembly. In this work, we characterized the assemblies of heptapeptides with various side chain moieties and their chiral variants using STM. Specifically, two pairs of amino acids, Gln (Q) and Asn (N), Glu (E) and Asp (D), having one methylene difference in their side chains, are selected to elucidate the steric dependence of amino acid chiral effects on surface-bound peptide assemblies. The observed heptapeptide assembly structures reveal that chirality switching of a single amino acid is able to destabilize the surface-mediated peptide assemblies, and this disturbance effect can be positively correlated with the steric hindrance of amino acid side chains. Furthermore, the strength of the impact due to chiral conversion on heptapeptide assembly structure is noticeably dependent on the mutation sites, indicative of structural heterogeneity of chiral effects. These results could contribute to the molecular insights of chirality-induced stereochemical interactions in peptide assembly.

Identifying Terminal Assembly Propensity of Amyloidal Peptides by Scanning Tunneling Microscopy.

The abnormal accumulation of beta-amyloids (Aß) in brain is considered as a key initiating cause for Alzheimer's disease (AD) due to their richness in plaques and self-aggregate propensity. In recent studies, N-terminally extended Aß peptides (NTE-Aß) with the N-terminus originating prior to the canonical ß-secretase cleavage site were found in humans and suggested to have possible relevance to AD. However, the effects of the extended N-terminus on the amyloidegenic structure and aggregation propensity have not been fully elucidated. Herein, we characterized the assembly structures of Aß1-42, Aß(-5)-42, Aß(-10)-42 and Aß(-15)-42 with both normal and reversed sequences on highly oriented pyrolytic graphite (HOPG) surfaces with scanning tunneling microscopy (STM). The molecularly resolved surface-mediated peptide assemblies enable identification of amyloidegenic fragments. The observations reveal that the assembly propensity of the C-terminal strand of Aß1-42 is highly conserved and insensitive to N-terminal extensions. In contrast, different assembly structures of the N-terminal strand of Aß variants can be observed with possible assignment of varied amyloidegenic fragments in the extended N-termini, which may contribute to the varied aggregation propensities of Aß42 species.

Peptide Self-Assembly and Its Modulation: Imaging on the Nanoscale.

This chapter intends to review the progress in obtaining site-specific structural information for peptide assemblies using scanning tunneling microscopy. The effects on assembly propensity due to mutations and modifications in peptide sequences, small organic molecules and conformational transitions of peptides are identified. The obtained structural insights into the sequence-dependent assembly propensity could inspire rational design of peptide architectures at the molecular level.

Design and study of lipopeptide inhibitors on preventing aggregation of human islet amyloid polypeptide residues 11-20.

Type 2 diabetes mellitus, a kind of conformational disease, has become an epidemic disease, which seriously endangers the quality of life and health of human beings. The deposition of human islet amyloid polypeptide (hIAPP) has been considered as one of the major pathological features of type 2 diabetes mellitus. As lipopeptides have some hydrophobic groups, which are similar to the reported aggregation inhibitors, and some lipopeptides could prevent cells from depositing of amyloid fibrils, several potential lipopeptide inhibitors have been engineered and synthesized, which have been assessed for their inhibitory effect in preventing amyloid fibrils formation of hIAPP11-20 by using the conventional thioflavin-T fluorescence assay and new technique microscale thermophoresis (MST). The final amyloid fibrils of hIAPP11-20 were characterized by transmission electron microscopy. Results suggested that with the increasing length of alkyl chain, the antiaggregation efficiency of lipopeptide inhibitors towards hIAPP11-20 increased gradually. Meanwhile, the amount of arginines, which represent the head groups of lipopeptides, may also have some influence. The binding events also showed that the inhibitory efficiency of these lipopeptide inhibitors was enhanced with the increase of affinities between lipopeptides and hIAPP11-20 , which were obtained from MST. This study demonstrated the efficiency of lipopeptides in inhibiting the aggregation of hIAPP11-20 and proved that MST could be regarded as an appropriate and rapid method to screen potential inhibitors of hIAPP11-20 or other amyloid proteins. This study also broadens the types of inhibitors on inhibiting amyloid formation of hIAPP.

Activity of a novel-designed antimicrobial peptide and its interaction with lipids.

A new antimicrobial peptide l-RW containing double amphipathic binding sequences was designed, and its biological activities were investigated in the present study. L-RW showed antibacterial activity against several bacterial strains but low cytotoxicity to mammalian cells and low hemolytic activity to red blood cells, which makes it a potential and promising peptide for further development. Microscale thermophoresis (MST), a new technique, was applied to study the antimicrobial peptide-lipid interaction for the first time, which examined the binding affinities of this new antimicrobial peptide to various lipids, including different phospholipids, mixture lipids and bacterial lipid extracts. The results demonstrated that l-RW bound preferentially to negatively charged lipids over neutral lipids, which was consistent with the biological activities, revealing the important role of electrostatic interaction in the binding process. L-RW also showed higher binding affinity for lipid extract from Staphyloccocus aureus compared with Pseudomonas aeruginosa and Escherichia coli, which were in good agreement with the higher antibacterial activity against S. aureus than P. aeruginosa and E. coli, suggesting that the binding affinity is capable to predict the antibacterial activity to some extent. Additionally, the binding of l-RW to phospholipids was also performed in fetal bovine serum solution by MST, which revealed that the components in biological solution may have interference with the binding event. The results proved that MST is a useful and potent tool in antimicrobial peptide-lipid interaction investigation.

Comparison of binding characteristics and in vitro activities of three inhibitors of vascular endothelial growth factor A.

The objectives of this study were to evaluate the relative binding and potencies of three inhibitors of vascular endothelial growth factor A (VEGF), used to treat neovascular age-related macular degeneration, and assess their relevance in the context of clinical outcome. Ranibizumab is a 48 kDa antigen binding fragment, which lacks a fragment crystallizable (Fc) region and is rapidly cleared from systemic circulation. Aflibercept, a 110 kDa fusion protein, and bevacizumab, a 150 kDa monoclonal antibody, each contain an Fc region. Binding affinities were determined using Biacore analysis. Competitive binding by sedimentation velocity analytical ultracentrifugation (SV-AUC) was used to support the binding affinities determined by Biacore of ranibizumab and aflibercept to VEGF. A bovine retinal microvascular endothelial cell (BREC) proliferation assay was used to measure potency. Biacore measurements were format dependent, especially for aflibercept, suggesting that biologically relevant, true affinities of recombinant VEGF (rhVEGF) and its inhibitors are yet to be determined. Despite this assay format dependency, ranibizumab appeared to be a very tight VEGF binder in all three formats. The results are also very comparable to those reported previously.1-3 At equivalent molar ratios, ranibizumab was able to displace aflibercept from preformed aflibercept/VEGF complexes in solution as assessed by SV-AUC, whereas aflibercept was not able to significantly displace ranibizumab from preformed ranibizumab/VEGF complexes. Ranibizumab, aflibercept, and bevacizumab showed dose-dependent inhibition of BREC proliferation induced by 6 ng/mL VEGF, with average IC50 values of 0.088 ± 0.032, 0.090 ± 0.009, and 0.500 ± 0.091 nM, respectively. Similar results were obtained with 3 ng/mL VEGF. In summary Biacore studies and SV-AUC solution studies show that aflibercept does not bind with higher affinity than ranibizumab to VEGF as recently reported,4 and both inhibitors appeared to be equipotent with respect to their ability to inhibit VEGF function.

Zoledronic acid and ibandronate-induced nephrotoxicity in 2D and 3D proximal tubule cells derived from human and rat.

Drug-induced proximal tubule (PT) injury remains a serious safety concern throughout drug development. Traditional in vitro 2-dimensional (2D) and preclinical in vivo models often fail to predict drug-related injuries presented in clinical trials. Various 3-dimensional (3D) microphysiological systems (MPSs) have been developed to mimic physiologically relevant properties, enabling them to be more predictive toward nephrotoxicity. To explore the capabilities of an MPS across species, we compared cytotoxicity in hRPTEC/TERT1s and rat primary proximal tubular epithelial cells (rPPTECs) following exposure to zoledronic acid and ibandronate (62.5-500 µM), and antibiotic polymyxin B (PMB) (50 and 250 µM, respectively). For comparison, we investigated cytotoxicity using 2D cultured hRPTEC/TERT1s and rPPTECs following exposure to the same drugs, including overlapping concentrations, as their 3D counterparts. Regardless of the in vitro model, bisphosphonate-exposed rPPTECs exhibited cytotoxicity quicker than hRPTEC/TERT1s. PMB was less sensitive toward nephrotoxicity in rPPTECs than hRPTEC/TERT1s, demonstrating differences in species sensitivity within both 3D and 2D models. Generally, 2D cultured cells experienced faster drug-induced cytotoxicity compared to the MPSs, suggesting that MPSs can be advantageous for longer-term drug-exposure studies, if warranted. Furthermore, ibandronate-exposed hRPTEC/TERT1s and rPPTECs produced higher levels of inflammatory and kidney injury biomarkers compared to zoledronic acid, indicating that ibandronate induces acute kidney injury, but also a potential protective response since ibandronate is less toxic than zoledronic acid. Our study suggests that the MPS model can be used for preclinical screening of compounds prior to animal studies and human clinical trials.

Mechanism study of aging oil demulsification and dehydration under ultrasonic irradiation.

With the tertiary oil recovery in the oilfield, the content of aging oil emulsion with high water content and complex components has become more prevalent, so it is crucial for aging oil to break the emulsification. In this paper, the experimental laws of water content are explored under the conditions of different transducer input powers through the ultrasonic reforming of aging oil, and the microscopic topography, particle size, components, etc. of oil samples before and after the irradiation of ultrasound are characterized through the microscopic analysis, particle size analysis and component analysis and other ways. The results show that the oil samples achieve the effect of demulsification and dehydration in the presence of ultrasonic cavitation effect, with a maximum dehydration rate of 98.24 %, and that the dehydration rate follows an "M-type" trend with the increase of power. The results of microscopic and particle size analyses demonstrate that ultrasonic irradiation destabilizes the oil-water interfacial membrane, and causes droplets of different sizes to collide, agglomerate, and settle. It was also observed that the droplets of the emulsion system are more evenly distributed and the intervals are increased. Furthermore, we hypothesize that ultrasound may be less irreversible in demulsification and dehydration of aging oil.

Metronomic chemotherapy plus anti-PD-1 in metastatic breast cancer: a Bayesian adaptive randomized phase 2 trial.

It remains unclear whether metronomic chemotherapy is superior to conventional chemotherapy when combined with immune checkpoint blockade. Here we performed a phase 2 clinical trial of metronomic chemotherapy combined with PD-1 blockade to compare the efficacy of combined conventional chemotherapy and PD-1 blockade using Bayesian adaptive randomization and efficacy monitoring. Eligible patients had metastatic HER2-negative breast cancer and had not received more than one prior line of standard chemotherapy. Patients (total n = 97) were randomized to receive (1) metronomic vinorelbine (NVB) monotherapy (n = 11), (2) NVB plus anti-PD-1 toripalimab (n = 7), (3) anti-angiogenic bevacizumab, NVB and toripalimab (n = 27), (4) conventional cisplatin, NVB and toripalimab (n = 26), or (5) metronomic cyclophosphamide, capecitabine, NVB and toripalimab (the VEX cohort) (n = 26). The primary endpoint was disease control rate (DCR). Secondary objectives included progression-free survival (PFS) and safety. The study met the primary endpoint. The VEX (69.7%) and cisplatin (73.7%) cohorts had the highest DCR. The median PFS of patients in the VEX cohort was the longest, reaching 6.6 months, followed by the bevacizumab (4.0 months) and cisplatin (3.5 months) cohorts. In general, the five regimens were well tolerated, with nausea and neutropenia being the most common adverse events. An exploratory mass cytometry analysis indicated that metronomic VEX chemotherapy reprograms the systemic immune response. Together, the clinical and translational data of this study indicate that metronomic VEX chemotherapy combined with PD-1 blockade can be a treatment option in patients with breast cancer. ClinicalTrials.gov Identifier: NCT04389073 .