Kiwi-Inspired Rational Nanoarchitecture with Intensified and Discrete Magneto-Fluorescent Functionalities for Ultrasensitive Point-of-Care Immunoassay.

Fluorescent lateral flow immunoassays (FLFIA) is a well-established rapid detection technique for quantitative analysis. However, achieving accurate analysis of biomarkers at the pg mL-1 level using FLFIA still poses challenges. Herein, an ultrasensitive FLFIA platform is reported utilizing a kiwi-type magneto-fluorescent silica nanohybrid (designated as MFS) that serves as both a target-enrichment substrate and an optical signal enhancement label. The spatially-layered architecture comprises a Fe3O4 core, an endocarp-fibers like dendritic mesoporous silica, seed-like quantum dots, and a kiwi-flesh like silica matrix. The MFS demonstrates heightened fluorescence brightness, swift magnetic response, excellent size uniformity, and dispersibility in water. Through liquid-phase capturing and fluorescence-enhanced signal amplification, as well as magnetic-enrichment sample amplification and magnetic-separation noise reduction, the MFS-based FLFIA is successfully applied to the detection of cardiac troponin I that achieved a limit of detection at 8.4 pg mL-1, tens of times lower than those of previously published fluorescent and colorimetric lateral flow immunoassays. This work offers insights into the strategic design of magneto-fluorescent synergetic signal amplification on LFIA platform and underscores their prospects in high-sensitive rapid and on-site diagnosis of biomarkers.

Surface-Engineered Polygonatum Sibiricum Polysaccharide CaCO3 Microparticles as Novel Vaccine Adjuvants to Enhance Immune Response.

Micro- and nanoparticles delivery systems have been widely studied as vaccine adjuvants to enhance immunogenicity and sustain long-term immune responses. Polygonatum sibiricum polysaccharide (PSP) has been widely studied as an immunoregulator in improving immune responses. In this study, we synthesized and characterized cationic modified calcium carbonate (CaCO3) microparticles loaded with PSP (PEI-PSP-CaCO3, CTAB-PSP-CaCO3), studied the immune responses elicited by PEI-PSP-CaCO3 and CTAB-PSP-CaCO3 carrying ovalbumin (OVA). Our results demonstrated that PEI-PSP-CaCO3 significantly enhanced the secretion of IgG and cytokines (IL-4, IL-6, IFN-γ, and TNF-α) in vaccinated mice. Additionally, PEI-PSP-CaCO3 induced the activation of dendritic cells (DCs), T cells, and germinal center (GC) B cells in draining lymph nodes (dLNs). It also enhanced lymphocyte proliferation, increased the ratio of CD4+/CD8+ T cells, and elevated the frequency of CD3+ CD69+ T cells in spleen lymphocytes. Therefore, PEI-PSP-CaCO3 microparticles induced a stronger cellular and humoral immune response and could be potentially useful as a vaccine delivery and adjuvant system.

Improving pharmacological activities of thrombopoietin mimetic peptide by genetic fusion to albumin-binding domain.

OBJECTIVE: Thrombopoietin mimetic peptide (TMP), an analog of natural thrombopoietin, can be used to treat primary immune thrombocytopenia. However, the short half-life of TMP limits its application in clinics. The present study aimed to improve the stability and biological activity of TMP in vivo via genetic fusion to the albumin-binding protein domain (ABD). RESULTS: TMP dimer was genetically fused to the N-terminal or C-terminal of ABD, denoted as TMP-TMP-ABD and ABD-TMP-TMP. A Trx-tag was used to improve the fusion proteins' expression levels effectively. ABD-fusion TMP proteins were produced in Escherichia coli and purified by Ni2+-NTA and SP ion exchange column. Albumin binding studies in vitro showed that the fusion proteins could effectively bind to serum albumin to extend their half-lives. The fusion proteins effectively induced platelet proliferation in healthy mice, and the platelet count was increased by more than 2.3-fold compared with the control group. The increased platelet count induced by the fusion proteins lasted 12 days compared with the control group. The increasing trend was maintained for 6 days before a decline occurred after the last injection in the fusion-protein-treated mice group. CONCLUSIONS: ABD can effectively improve the stability and pharmacological activity of TMP by binding to serum albumin, and the ABD-fusion TMP protein can promote platelet formation in vivo.

Clinical characteristics of COVID-19 patients with hepatitis B virus infection - a retrospective study.

BACKGROUND & AIMS: The outbreak of coronavirus disease 2019 (COVID-19) has been declared a pandemic. Although COVID-19 is caused by infection in the respiratory tract, extrapulmonary manifestations including dysregulation of the immune system and hepatic injury have been observed. Given the high prevalence of hepatitis B virus (HBV) infection in China, we sought to study the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and HBV coinfection in patients. METHODS: Blood samples of 50 SARS-CoV-2 and HBV coinfected patients, 56 SARS-CoV-2 mono-infected patients, 57 HBeAg-negative chronic HBV patient controls and 57 healthy controls admitted to Renmin Hospital of Wuhan University were collected in this study. Complete blood count and serum biochemistry panels including markers indicative of liver functions were performed. Cytokines including IFN-γ, TNF-α, IL-2, IL-4, IL-6 and IL-10 were evaluated. T cell, B cell and NK cell counts were measured using flow cytometry. RESULTS: SARS-CoV-2 and HBV coinfection did not significantly affect the outcome of the COVID-19. However, at the onset of COVID-19, SARS-CoV-2 and HBV coinfected patients showed more severe monocytopenia and thrombocytopenia as well as more disturbed hepatic function in albumin production and lipid metabolism. Most of the disarrangement could be reversed after recovery from COVID-19. CONCLUSIONS: While chronic HBV infection did not predispose COVID-19 patients to more severe outcomes, our data suggest SARS-CoV-2 and HBV coinfection poses a higher extent of dysregulation of host functions at the onset of COVID-19. Thus, caution needs to be taken with the management of SARS-CoV-2 and HBV coinfected patients.

Absent immune response to SARS-CoV-2 in a 3-month recurrence of coronavirus disease 2019 (COVID-19) case.

BACKGROUND: The viral persistence in patients with Coronavirus Disease 2019 (COVID-19) remains to be investigated. METHODS: We investigated the viral loads, therapies, clinical features, and immune responses in a 70-year patient tested positive for SARS-CoV-2 for 3 months. FINDINGS: The patient exhibited the highest prevalence of abnormal indices of clinical features and immune responses at the first admission, including fever (38.3 â„ƒ), decreased lymphocytes (0.83 × 109/L) and serum potassium (3.1 mmol/L), as well as elevated serum creatinine (115 µmol/L), urea (8.6 mmol/L), and C-reactive protein (80 mg/L). By contrast, at the second and the third admission, these indices were all normal. Through three admissions, IL-2 increased from 0.14 pg/mL, 0.69 pg/mL, to 0.91 pg/mL, while IL-6 decreased from 11.78 pg/mL, 1.52 pg/mL, to 0.69 pg/mL, so did IL-10 from 5.13 pg/mL, 1.85 pg/mL, to 1.75 pg/mL. The steady declining trend was also found in TNF-α (1.49, 1.15, and 0.85 pg/mL) and IFN-γ (0.64, 0.42, and 0.27 pg/mL). The threshold cycle values of RT-PCR were 26.1, 30.5, and 23.5 for ORFlab gene, and 26.2, 30.6, and 22.7 for N gene, showing the patient had higher viral loads at the first and the third admission than during the middle term of the disease. The patient also showed substantially improved acute exudative lesions on the chest CT scanning images. CONCLUSIONS: The patient displayed declining immune responses in spite of the viral shedding for 3 months. We inferred the declining immune responses might result from the segregation of the virus from the immune system.

Low serum level of apolipoprotein A1 may predict the severity of COVID-19: A retrospective study.

BACKGROUND: Dyslipidemia has been observed in patients with coronavirus disease 2019 (COVID-19). This study aimed to investigate blood lipid profiles in patients with COVID-19 and to explore their predictive values for COVID-19 severity. METHODS: A total of 142 consecutive patients with COVID-19 were included in this single-center retrospective study. Blood lipid profile characteristics were investigated in patients with COVID-19 in comparison with 77 age- and gender-matched healthy subjects, their predictive values for COVID-19 severity were analyzed by using multivariable logistic regression analysis, and their prediction efficiencies were evaluated by using receiver operator characteristic (ROC) curves. RESULTS: There were 125 and 17 cases in the non-severe and severe groups, respectively. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein A1 (ApoA1) gradually decreased across the groups in the following order: healthy controls, non-severe group, and severe group. ApoA1 was identified as an independent risk factor for COVID-19 severity (adjusted odds ratio [OR]: 0.865, 95% confidence interval [CI]: 0.800-0.935, p < 0.001), along with interleukin-6 (IL-6) (adjusted OR: 1.097, 95% CI: 1.034-1.165, p = 0.002). ApoA1 exhibited the highest area under the ROC curve (AUC) among all single markers (AUC: 0.896, 95% CI: 0.834-0.941); moreover, the risk model established using ApoA1 and IL-6 enhanced prediction efficiency (AUC: 0.977, 95% CI: 0.932-0.995). CONCLUSION: Blood lipid profiles in patients with COVID-19 are quite abnormal compared with those in healthy subjects, especially in severe cases. Serum ApoA1 may represent a good indicator for predicting the severity of COVID-19.

The potential role of serum angiotensin-converting enzyme in coronavirus disease 2019.

BACKGROUND: To explore the clinical significance of serum angiotensin-converting enzyme (ACE) activity in coronavirus disease 2019 (COVID-19). METHODS: In this retrospective study, a total of 136 consecutive patients with confirmed COVID-19 were recruited. Demographic and clinical data were recorded. The serum ACE activity was measured at baseline and during the recovery phase, and its relationship with clinical condition was analyzed. RESULTS: Of the 136 patients with confirmed COVID-19, the 16 severe patients were older and had a higher body mass index (BMI) and proportion of hypertension than the 120 nonsevere patients. In comparison to those of normal controls, the baseline serum ACE activities of subjects in the severe group and nonsevere group were decreased, with the lowest level in the severe group. However, the serum ACE activity increased in the recovery phase, and there were no significant differences among the severe group, nonsevere group and normal control group. CONCLUSION: Serum ACE activity could be used as a marker to reflect the clinical condition of COVID-19 since low activity was associated with the severity of COVID-19 at baseline, and the activity increased with the remission of the disease.

Knockdown XIST alleviates LPS-induced WI-38 cell apoptosis and inflammation injury via targeting miR-370-3p/TLR4 in acute pneumonia.

Pneumonia is an inflammatory disease that occurs in the lungs associated with pathogens or other factors. It has been well established that long noncoding RNA X inactivate-specific transcript (XIST) is involved in several cancers. The present study focused on the effect and detailed mechanism of XIST in lipopolysaccharide (LPS)-induced injury in pneumonia. Here, XIST was silenced by transfection with XIST-targeted siRNA, and then, mRNA expression, cell viability, apoptosis, and protein expression were, respectively, assessed by qRT-PCR, CCK-8, flow cytometry, and Western blotting. Luciferase reporter, RIP, and RNA pull-down assays were used to detect the combination of miR-370-3p and XIST. Besides, the tested proinflammatory factors were analysed by qRT-PCR and Western blot, and their productions were quantified by ELISA. The results showed that XIST expression was robustly increased in serum of patients with acute-stage pneumonia and LPS-induced WI-38 human lung fibroblasts cells. Functional analyses demonstrated that knockdown of XIST remarkably alleviated LPS-induced cell injury through increasing cell viability and inhibiting apoptosis and inflammatory cytokine levels. Mechanistically, XIST functioned as a competitive endogenous RNA (ceRNA) by effectively binding to miR-370-3p and then restoring TLR4 expression. More importantly, miR-370-3p inhibitor abolished the function of XIST knockdown on cell injury and JAK/STAT and NF-κB pathways. Taken together, XIST may be involved in progression of cell inflammatory response, and XIST/miR-370-3p/TLR4 axis thus may shed light on the development of novel therapeutics to the treatment of acute stage of pneumonia. SIGNIFICANCE OF THE STUDY: Our study demonstrated that XIST was highly expressed in patients with acute stage of pneumonia. Knockdown of XIST remarkably alleviated LPS-induced cell injury through increasing cell viability and inhibiting apoptosis and inflammatory cytokine levels through regulating JAK/STAT and NF-κB pathways.

High-affinity graphene oxide-encapsulated magnetic Zr-MOF for pretreatment and rapid determination of the photosensitizers hematoporphyrin and hematoporphyrin monomethyl ether in human urine prior to UPLC-HRMS.

In this paper, a high-affinity graphene oxide-encapsulated magnetic Zr-MOF (GO-Mag@Zr-MOF) was synthesized and characterized by SEM, TEM, and XPS for its morphology, structure, and components. Subsequently, the as-prepared GO-Mag@Zr-MOF was, for the first time, employed as magnetic solid-phase extraction (MSPE) adsorbent for pretreatment and determination of photodynamic therapy (PDT) with the photosensitizers hematoporphyrin (Hp) and hematoporphyrin monomethyl ether (HMME) in human urine samples coupled with ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The synthesized GO-Mag@Zr-MOF revealed excellent adsorption efficiency for Hp and HMME in urine samples. Under optimal conditions, the spiked recoveries of the developed method were in the range of 89.5-105.6% with RSDs less than 10%. The limits of detection (LODs) were found to be 0.036 and 0.042 µg/L for Hp and HMME, respectively, while limits of quantitation (LOQs) were 0.12 and 0.14 µg/L. The proposed method was found to be rapid, effective, sensitive, and accurate for clinical analysis. Moreover, this paper, for the first time, carefully expounded the mass spectrum cracking mechanisms of Hp and HMME. Graphical abstract ᅟ.

Hepatoma cell-derived leptin downregulates the immunosuppressive function of regulatory T-cells to enhance the anti-tumor activity of CD8+ T-cells.

The adaptive immune response against hepatocellular carcinoma (HCC) could be a therapeutic target to restrain HCC initiation and growth. The interactions between hepatoma cells and immune cells modify the anti-tumor immunity to influence hepatoma cell survival. To explore the potential interplay between hepatoma cells and anti-HCC T-cells, we conducted a HCC induction mouse model to analyze the phenotypic and functional alterations of T-cell subsets. We found that both hepatoma tissues and hepatoma cell lines substantially produced higher leptin, which is an adipokine usually expressed in fat tissue, than normal liver tissue or hepatocytes. We also found that regulatory T-cells (Tregs), effector CD4(+) T-cells and CD8(+) T-cells upregulated expression of leptin receptor (LEPR) in spleens and livers after HCC induction. In vitro study showed that macrophages and dendritic cells isolated from HCC livers upregulated LEPR expression on T-cells. Leptin inhibited Treg activation and function in vitro, demonstrated by lower expression of TGF-ß, IL-10, CTLA4 and GITR in Tregs, as wells weaker suppression of CD8(+) T-cell proliferation and production of cytotoxic mediators. In addition, silencing LEPR in Tregs favored tumor growth in a hepatoma cell line allograft model. Taken together, our study suggests that hepatoma cells could enhance anti-HCC immunity through secreting leptin to down-regulate Treg activity and subsequently promote CD8(+) T-cell response.

Hepatitis B virus inhibits apolipoprotein A5 expression through its core gene.

BACKGROUND: Hepatitis B virus (HBV) infection causes lipid metabolism disorders. Apolipoprotein A5 (ApoA5) is a new apolipoprotein family member that plays an important role in the regulation of lipid metabolism. The present study was to investigate the impact of HBV on ApoA5 expression and its regulatory mechanism. METHODS: Reverse transcription polymerase chain reaction (RT-PCR) and western blotting were used to measure ApoA5 mRNA and protein expression in HepG2 and HepG2.2.15 cells. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum ApoA5 levels in healthy individuals and HBV patients. HBV infectious clone pHBV1.3 or individual plasmids expressing the HBV genome was cotransfected with the ApoA5 promoter pGL3-Apo5-LUC plasmid into HepG2 cells to assess the luciferase activity. RT-PCR and western blotting methods were used to detect Apo5 mRNA and protein expression, respectively. RESULTS: The ApoA5 mRNA and protein expression levels were decreased in HepG2.2.15 cells compared with the control HepG2 cells. The serum ApoA5 levels were 196.4 ± 28.7 µg/L in the healthy individuals and 104.5 ± 18.3 µg/L in the HBV patients, statistical analysis showed that the ApoA5 levels were significantly lower in HBV patients than in the healthy individuals (P < 0.05). pHBV1.3 and its core gene inhibited ApoA5 promoter activity and mRNA and protein expression in HepG2 cells. CONCLUSION: HBV inhibits ApoA5 expression at both the transcriptional and translational levels through its core gene.

Synthesis of weak cation exchange/C18 bifunctional magnetic polymers for pretreatment and determination of glufosinate and its two metabolites in plasma samples.

This study focuses on the purification and detection of glufosinate (GLUF) and its metabolites N-acetyl GLUF and MPP in plasma samples. A Dikma Polyamino HILIC column was used for the effective retention and separation of GLUF and its metabolites, and the innovative addition of a low concentration of ammonium fluoride solution to the mobile phase effectively improved the detection sensitivity of the target analytes. Monodisperse core-shell weak cation exchange (WCX)/C18 bifunctional magnetic polymer composites (Fe3O4@WCX/C18) were prepared in a controllable manner, and their morphology and composition were fully characterized. The Fe3O4@WCX/C18 microspheres were used as a magnetic solid-phase extraction (MSPE) adsorbent for the sample purification and detection of GLUF and its metabolites in plasma samples combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The purification conditions of Fe3O4@WCX/C18 microspheres for GLUF and its metabolites in spiked plasma samples were optimized to achieve the best MSPE efficiency. The purification mechanisms of the target analytes in plasma samples include electrostatic attraction and hydrophobic interactions. Furthermore, the effect of the molar ratio of the two functional monomers 4-VBA and 1-octadecene in the adsorbent was optimized and it shows that the bifunctional components WCX/C18 have a synergistic effect on the determination of GLUF and its metabolites in plasma samples. In addition, the present study compared the purification performance of the Fe3O4@WCX/C18 microsphere-based MSPE method with that of the commercial Oasis WCX SPE method, and the results showed that the Fe3O4@WCX/C18 microsphere-based MSPE method established in this work had a stronger ability to remove matrix interferences. Under optimal purification conditions, the recoveries of GLUF and its metabolites in plasma were 87.6-111 % with relative standard deviations (RSDs) ranging from 0.2 % to 4.8 %. The limits of detection (LODs, S/N≥3) and limits of quantification (LOQs, S/N≥10) were 0.10-0.18 µg/L and 0.30-0.54 µg/L, respectively. The MSPE-LC-MS/MS method developed in this study is fast, simple, accurate and sensitive and can be used to confirm GLUF intoxication based not only on the detection of the GLUF prototype but also on the detection of its two metabolites.

METTL3 facilitates stemness properties and tumorigenicity of cancer stem cells in hepatocellular carcinoma through the SOCS3/JAK2/STAT3 signaling pathway.

Liver cancer stem cells (LCSCs) contribute to tumor recurrence and cancer cell proliferation in patients with hepatocellular carcinoma (HCC). METTL3-catalyzed m6A modification is relevant to the cancer stem cell (CSC) phenotype, including LCSCs. LCSCs were isolated from MHCC-97H and HepG2 cells through flow cytometry. UALCAN data were used to analyze the expression of METTL3 in liver hepatocellular carcinoma (LIHC) tissues. Loss- and gain-of-function experiments were utilized to assess the biological effects of METTL3 and SOCS3 on the proliferation and stemness phenotypes in vitro and in vivo. The mechanisms underlying the impact of METTL3 were explored using qPCR, MeRIP-qPCR, dual-luciferase reporter, and western blot assays. METTL3 was significantly upregulated in LIHC tissues according to the UALCAN database. METTL3 was highly expressed in LIHC and was significantly correlated with individual cancer stage, tumor grade and lymph node metastasis. Patients with low METTL3 expression had a longer overall survival time based on the data from UALCAN. In addition, the level of METTL3 was enhanced in LCSCs and decreased in non-LCSCs compared to HCC cells. Moreover, overexpression of METTL3 stimulated the proliferation and stemness of LCSCs in vitro and in vivo, while loss of METTL3 impeded it. Bioinformatics analysis combined with validation experiments determined that m6A was modified by METTL3-targeting SOCS3 mRNA. METTL3 had side effects regarding the stability of SOCS3 mRNA. SOCS3 overexpression impaired and SOCS3 depletion facilitated the development of LCSCs via the JAK2/STAT3 pathway. Furthermore, METTL3 depletion suppressed proliferation and stemness in LCSCs, which was restored by SOCS3 knockdown or colivelin treatment. We discovered that METTL3 facilitated the stemness and tumorigenicity of LCSCs by modifying SOCS3 mRNA with m6A.

The trade-off of Vibrio parahaemolyticus between bacteriophage resistance and growth competitiveness.

Vibrio parahaemolyticus is a food-borne pathogen, which is often isolated from various seafood products. In this study, two kinds of bacteriophages was isolated from the offshore sediments samples. The anti-phage mutant strain were obtained after seventeen rounds of co-culture of Vibrio parahaemolyticus and mixed bacteriophage, multigroup sequencing was carried out on spontaneous the anti-phage mutant strain and the wild-type strain. We used the Sanger sequencing to verify the accuracy of the mutation sites. Biolog GEN III MicroPlates were used to evaluate the metabolic capacity of wild-type strains and the anti-phage mutant strain. In this study, we found that with flaG gene (slight homology to N terminus of multiple flagellins) mutated, making the bacteriophage unable to absorb to the cell surface of the host. And, the growth competitiveness of the anti-phage mutant strain is lower than the wild-type strain. These results indicated that the fitness cost, including loss of the growth competitiveness, constitutes a barrier to the prevalence of these defense mechanisms. And the selection pressure on different anti-phage strategies depends on the trade-off between mortality imposed by bacteriophages and fitness cost of the defense strategy under the given environmental conditions. In conclusion, this study provides valuable insights into the phage-host interaction and phage resistance in Vibrio parahaemolyticus. Our study provided knowledge for the evolutionary adaption of bacteria against the bacteriophage, which could add more information to understand the phage resistance mechanism before applying in the industry.

Advances and challenges of exosome-derived noncoding RNAs for hepatocellular carcinoma diagnosis and treatment.

Exosomes, also termed extracellular vesicles (EVs), are an important component of the tumor microenvironment (TME) and exert versatile effects on the molecular communications in the TME of hepatocellular carcinoma (HCC). Exosome-mediated intercellular communication is closely associated with the tumorigenesis and development of HCC. Exosomes can be extracted through ultracentrifugation and size exclusion, followed by molecular analysis through sequencing. Increasing studies have confirmed the important roles of exosome-derived ncRNAs in HCC, including tumorigenesis, progression, immune escape, and treatment resistance. Due to the protective membrane structure of exosomes, the ncRNAs carried by exosomes can evade degradation by enzymes in body fluids and maintain good expression stability. Thus, exosome-derived ncRNAs are highly suitable as biomarkers for the diagnosis and prognostic prediction of HCC, such as exosomal miR-21-5p, miR-221-3p and lncRNA-ATB. In addition, substantial studies revealed that the up-or down-regulation of exosome-derived ncRNAs had an important impact on HCC progression and response to treatment. Exosomal biomarkers, such as miR-23a, lncRNA DLX6-AS1, miR-21-5p, lncRNA TUC339, lncRNA HMMR-AS1 and hsa_circ_0004658, can reshape immune microenvironment by regulating M2-type macrophage polarization and then promote HCC development. Therefore, by controlling exosome biogenesis and modulating exosomal ncRNA levels, HCC may be inhibited or eliminated. In this current review, we summarized the recent findings on the role of exosomes in HCC progression and analyzed the relationship between exosome-derived ncRNAs and HCC diagnosis and treatment.

Exploring a novel long-acting glucagon-like peptide-1 receptor agonist built on the albumin-binding domain and XTEN scaffolds.

In recent years, glucagon-like peptide-1 (GLP-1) has demonstrated considerable potential in the treatment of type 2 diabetes (T2D) and obesity. However, the half-life of naturally occurring GLP-1 is quite short in vivo. Two common strategies employed for half-life extension are the use of the Albumin-binding domain (ABD) and XTEN polypeptide, which operate through different mechanisms. In this study, we designed an innovative GLP-1 receptor agonist with an extended duration of action. This new construct incorporated an albumin binding domain (ABD) and an XTEN sequence (either XTEN144 or XTEN288) as carriers. We referred to these fusion proteins as GLP-ABD-XTEN144 and GLP-ABD-XTEN288. In an E. coli system, the said constructs were efficaciously produced in substantial quantity. It was observed from in vitro studies that the fusion protein GLP-ABD-XTEN144 demonstrated a five times stronger affinity towards human serum albumin (HSA), boasting a binding affinity (Kd) of 5.50 nM. This was in contrast to GLP-ABD-XTEN288, whose Kd value was registered at 27.78 nM. Moreover, GLP-ABD-XTEN144 presented a half-life of 12.9 h in mice, thus exceeding the corresponding value for GLP-ABD-XTEN288, 7.32 h in mice. Both these fusion proteins significantly mitigated non-fasting blood sugar levels and overall food consumption for 48 h subsequent to a one-time injection in mice. Notably, GLP-ABD-XTEN144 exhibited more pronounced hypoglycemic activity and food inhibitory effects than GLP-ABD-XTEN288. The designed GLP-ABD-XTEN144 fusion protein shows promising prospects for clinical application in T2D treatment. Our findings also suggest that ABD and XTEN polypeptides synergistically contribute to half-life extension, further enhancing the pharmacokinetic characteristics of a payload.

[Study on the relationship between hepatitis B virus genotypes and the effect of polyethylene glycol-interferon-alpha therapy on HBeAg-positive chronic hepatitis B].

OBJECTIVE: To investigate the efficacy of polyethylene glycol (PEG)-interferon α (PEG-IFNα) in treating HBeAg-positive chronic hepatitis B (CHB) and explore the relationship between hepatitis B virus (HBV) genotypes and the effect of interferon α (IFNα) therapy. METHODS: A total of 199 CHB patients with known genotypes were given subcutaneous injection of PEG-IFNα-2a or PEG-IFNα-2b once a week for 48 weeks, with another 24 weeks follow up. The seroconversion of HBeAg influenced by HBV genotypes were analyzed after discontinuation of treatment. RESULTS: In local area, genotype C was the major genotype [64.32% (128/199) ]. Except serum ALT and AST level, the differences in gender, age, liver inflammation, degree of liver fibrosis, HBeAg level and HBV DNA level between genotype B and C were not statistically significant (all P > 0.05). The seroconversion rate of HBeAg in patients with genotype B at early stage of therapy (3 months) was significantly higher than that of patients with genotype C [26.76% (19/71) vs 10.16% (13/128), χ(2) = 9.330, P = 0.002]. While at the end of follow-up, seroconversion rate of HBeAg in patients with genotype B (followed up for 6 months) was higher than that of patients with genotype C [39.44% (28/71) vs 30.47% (39/128)], but the difference was not statistically significant (χ(2) = 1.645, P = 0.200). By univariate analysis based on log-rank test, the time of HBeAg seroconversion in patients with genotype B was much earlier than that of genotype C [(13.99 ± 0.67) months vs (15.47 ± 0.41) months], but the difference was not statistically significant (P = 0.150). CONCLUSIONS: The seroconversion rate of HBeAg in patients with genotype B treated with PEG-IFNα was significantly higher than that of genotype C in early stage of therapy (3 months), while similar at the end of therapy.

[Liver histopathological features influencing HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B responding to Peg-IFN treatment].

OBJECTIVE: To investigate the therapeutic efficiency of antiviral treatment with pegylated-interferon (Peg-IFN) for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) and to explore whether liver histopathological features or other factors influence the HBeAg seroconversion treatment response. METHODS: Eighty HBeAg-positive CHB patients with diagnosis confirmed by liver puncture were treated with Peg-IFN(2a or 2b)body weight dose, once weekly). At treatment week 48, the rate of HBeAg seroconversion was determined and used to analyze the influence of liver histopathological features (liver biopsy assessment of: inflammation, graded G0 to G4; fibrosis stage, graded S0 to S4), sex, age, differential levels (pre-treatment baseline vs. week 48 post-treatment) of serum alanine transferase (ALT), and HBV DNA, by binary logistic analysis. RESULTS: At week 48, the overall rate of HBeAg seroconversion was 30.0%. The rate of HBeAg seroconversion gradually advanced with increased liver inflammation (X2 = 8.435, P = 0.015): 9.09% of the 22 patients with G1; 31.58% of the 38 patients with G2; 47.30% of the 19 patients with G3; the one patient with G4. In contrast, the rate of HBeAg seroconversion showed a much weaker association with liver fibrosis (X2 = 5.917, P = 0.116). Only baseline HBeAg level, and no other baseline index, was significantly different between the patients who achieved HBeAg seroconversion and those who did not. Liver inflammation and baseline HBeAg level were identified as influencing factors of HbeAg seroconversion in response to Peg-IFN treatment. CONCLUSION: Peg-IFN therapy induces a higher rate of HBeAg seroconversion in HBeAg-positive CHB patients with severe liver inflammation; histological analysis of pre-treatment liver biopsies may help to identify patients most likely to benefit from the antiviral regimen.

Albumin-binding DARPins as scaffold improve the hypoglycemic and anti-obesity effects of exendin-4 in vivo.

Type 2 diabetes mellitus (T2DM) and obesity have been considered epidemics and threats to public health worldwide. Exendin-4 (Ex), a GLP-1R agonist, has potential for treating T2DM and obesity. However, Ex has a half-life of only 2.4 h in humans and needs to be administered twice daily, which hampers its clinical application. In this study, we synthesized four new GLP-1R agonists by genetically fusing Ex to the N-terminus of HSA-binding ankyrin repeat proteins (DARPins) via linkers of different lengths, denoted as Ex-DARPin-GSx fusion proteins (x = 0, 1, 2, and 3). The Ex-DARPin fusion proteins were substantially stable, resulting in incomplete denaturation even at 80 °C. The in vitro bioactivity results demonstrated that Ex-DARPin fusion proteins could bind to HSA and activate GLP-1R. The Ex-DARPin fusion proteins had a comparable half-life (29-32 h), which is much longer than that of native Ex (0.5 h in rats). Subcutaneous injection of 25 nmol/kg Ex-DARPin fusion protein normalized blood glucose (BG) levels for at least 72 h in mice. The Ex-DARPin fusion proteins, injected at 25 nmol/kg every three days, significantly lowered BG, inhibited food consumption, and reduced body weight (BW) for 30 days in STZ-induced diabetic mice. Histological analysis of pancreatic tissues using H&E staining revealed that Ex-DARPin fusion proteins significantly improved the survival of pancreatic islets in diabetic mice. The differences in in vivo bioactivity of fusion proteins with different linker lengths were not significant. According to the findings in this study, long-acting Ex-DARPin fusion proteins designed by us hold promise for further development as antidiabetic and antiobesity therapeutic agents. Our findings also indicate that DARPins are a universal platform for generating long-acting therapeutic proteins via genetic fusion, thus broadening the application scope of DARPins.

Design of a Dual Agonist of Exendin-4 and FGF21 as a Potential Treatment for Type 2 Diabetes Mellitus and Obesity.

Background: Fibroblast growth factor 21 (FGF21) is a metabolic, endocrine hormone regulating insulin sensitivity, energy expenditure, and lipid metabolism. It has significant potential as a therapeutic drug for treating type 2 diabetes and obesity. However, the clinical efficacy of FGF21 analogs is limited due to their instability and short half-life. Glucagon-like peptide 1 (GLP-1) receptor agonists have been recognized as effective medications for type 2 diabetes mellitus and obesity over the past two decades. Methods: This study designed a new long-acting dual-agonist, exendin-4/FGF21, utilizing albumin-binding-designed ankyrin repeat proteins (DARPins) as carriers. The purified fusion proteins were subcutaneously injected into mice for pharmacokinetic and biological activity studies. Results: Ex-DARP-FGF21 had a high binding affinity for human serum albumin (HSA) in vitro and a prolonged half-life of 27.6 hours in vivo. Bioactivity results reveal that Ex-DARP-FGF21 significantly reduced blood glucose levels in healthy mice. Moreover, compared to Ex-DARP alone, the Ex-DARP-FGF21 dual agonist displayed enhanced blood glucose lowering bioactivity and superior body weight management in the diet-induced obesity (DIO) mouse model. Conclusions: These results indicate that the long-acting dual agonist of exendin-4 and FGF21 holds considerable potential as a treatment for type 2 diabetes mellitus (T2DM) and obesity in the future.