Tetrapeptide-based mimotope affinity monolith for the enrichment and analysis of anti-HER2 antibody and antibody-drug conjugate.

Selective enrichment and analysis of therapeutic antibodies in biological fluids are crucial for the development of biopharmaceuticals. Recently, peptide-based affinity chromatography has exhibited fascinating prospects for antibody enrichment due to the high affinity and specificity of small peptides. However, the post-modification approach of peptide ligands on the material surface is complicated and time-consuming. In this study, a methacrylate modified tetrapeptide (m-EDPW) was firstly demonstrated as the affinity ligand of trastuzumab (Kd = 1.91 ± 1.81 µM). Next, the m-EDPW based affinity monolith was prepared using a facile one-step polymerization method, which could overcome the drawbacks of traditional post-modification preparation strategies. Based on the monolith as described above, a simple enrichment approach was developed under the optimal washing and elution conditions. Based on the excellent properties, such as high porosity (53.09%), weak electrostatic interaction and suitable affinity (1.00 ± 2.14 µM for anti-HER2 ADC), this novel monolith exhibited good specificity and recovery for antibodies (91.6% for trastuzumab, 98.37% for anti-HER2 ADC), and low nonspecific adsorption for human serum albumin (DBC10% = 0.5 mg/g polymer). Particularly, this material was successfully applied to enrich trastuzumab and its related antibody-drug conjugate (ADC) from different cell culture medias. The dynamic tracking analysis of ADC in the critical quality attributes (e.g., charge variants, drug to antibody ratio and subunit conjugation ratio) was also achieved by combining the enrichment approach, capillary electrophoresis or reversed phase liquid chromatography. In summary, the exploited peptide-based mimotope affinity materials showed a great potential for the application in biopharmaceutical analysis.

Increased NKG2A+CD8+ T-cell exhaustion in patients with adenomyosis.

Immune dysregulation has long been proposed to be associated with adenomyosis, but the underlying mediators and mechanisms remain largely unexplored. Here, we used flow cytometry to investigate the alterations in immune cell subsets in adenomyotic uteri and analyze the phenotype and function of abnormal immune cells. We found that an increase in cluster of differentiation (CD)8+ T-cell number was the predominant alteration in ectopic lesions in patients with adenomyosis and was significantly associated with the severity of adenomyosis. Importantly, we identified an exhausted natural killer group protein 2A (NKG2A)+CD8+ T-cell subset that was associated with the severity of adenomyosis and found that the number of these cells was significantly increased in the eutopic endometrium and ectopic lesions. In addition, the increases in the expression of NKG2A ligand histocompatibility leucocyte antigen E and interleukin-15 in glandular epithelial cells in the adenomyotic microenvironment might contribute to CD8+ T-cell exhaustion by promoting NKG2A expression on CD8+ T cells or inhibiting the effector function of these cells. In conclusion, our data revealed a previously unrecognized role for NKG2A+CD8+ T-cell exhaustion in the pathogenesis of adenomyosis, indicating that therapeutic interventions designed to target and reinvigorate exhausted CD8+ T cells may be beneficial for patients with adenomyosis.

In vitro/in vivo degradation analysis of trastuzumab by combining specific capture on HER2 mimotope peptide modified material and LC-QTOF-MS.

Degradation analysis of therapeutic mAb is of high interest for critical quality attributes assessment and biotransformation studies. However, some obstacles, including low in vivo concentrations of mAb and complex biological matrices containing IgGs, could seriously interfere with mAb bioanalysis. In this study, a bioanalytical platform was developed for studying in vitro/in vivo modifications of trastuzumab, in which specific capture on mimotope peptide modified material was combined with trypsin digestion and LC-QTOF-MS analysis. It is worth noting that this material exhibits high specificity, suitable dynamic binding capacity, very little non-specific protein adsorption, and thus provides good enrichment and quantification performances for trastuzumab from patient serums. In particular, this bioanalytical platform was successfully applied to the dynamic monitoring of modifications of trastuzumab, such as deamidation, isomerization, oxidation and cyclization. Except for the faster deamidation of LC-Asn-30 and HC-Asn-387/392/393 under serum incubation, similar degradation trends for other sites were observed in phosphate buffer and spiked serum. Differences of peptide modification degrees of trastuzumab in patient serums were also observed. The novel platform exhibited superior specificity than Protein A/G/L based analytical methods, lower cost and higher stability than antigen or anti-idiotypic antibody based analytical methods, ensuring the evaluation of modification sites.

Two distinct resident macrophage populations coexist in the ovary.

Introduction: Tissue-resident macrophages (TRMs) are highly heterogeneous and have a complex and important role in tissue support, homeostasis, and function. The heterogeneity, maintenance, and function of TRMs, as one of the major immune cells in the ovary, are not well understood. Methods: Application of flow cytometry, Parabiosis, Fate mapping, Macrophage depletion, etc. Results: Here, we described two distinct macrophage subsets, F4/80hiCD11bint and F4/80intCD11bhi, with different phenotypic characteristics in the ovary of mice. The F4/80hiCD11bint population contained a distinct CD206+ subgroup and highly expressed CD81, while the F4/80intCD11bhi subset showed higher expression of CCR2 and TLR2. Notably, Ly6c+ macrophages were present almost exclusively in the F4/80intCD11bhi subpopulation. Combining in vivo fate mapping and parabiotic mouse models, we characterized the longevity and replenishment of the two macrophage populations. We found that both the F4/80hiCD11bint and F4/80intCD11bhi subsets were ovary-resident. Importantly, the F4/80hiCD11bint macrophages acted as a self-maintaining and long-lived population with a modest monocyte contribution at a steady state, and the F4/80intCD11bhi subpopulation had a relatively short lifespan with a greater contribution from monocytes. After macrophage ablation, disturbance of estradiol secretion and ovarian hemorrhage due to damaged vascular integrity was observed in mice. Discussion: Our data provide critical insights into ovarian macrophage heterogeneity and highlight the strategic role of TRMs in ovarian homeostasis and physiology.

LncRNA-OBFC2A targeted to Smad3 regulated Cyclin D1 influences cell cycle arrest induced by 1,4-benzoquinone.

Long-term exposure to benzene is associated with adverse health effects such as leukemia. Abnormal cell cycle progression has been reported participating in tumorigenesis. Our previous study found that lncRNA-OBFC2A was involved in benzene toxicity through regulating cell proliferation. However, the function of lncRNA-OBFC2A in the regulation of cell cycle remains obscure and the precise mechanisms need to be explored. In vitro study, results showed that benzene metabolic, 1,4-Benzoquinone (1,4-BQ), induced cell cycle arrest at the G1 phase accompanied with decreased expression of Cyclin D1 in a dose-dependently manner. Interestingly, lncRNA-OBFC2A overexpression was found in AHH-1 cells treated with 1,4-BQ and while interference with lncRNA-OBFC2A, the expression of Cyclin D1 were reversed. Further, we found that lncRNA-OBFC2A can interact with Smad3 to control cell cycle via modulating Cyclin D1 expression. In benzene exposed workers, the expression of lncRNA-OBFC2A and Smad3 increased while cyclin D1 decreased which was consistent with the in vitro experiment, meanwhile, the significant associations among them were also found. Thus, these findings indicate that lncRNA-OBFC2A targeted to Smad3 regulated cyclin D1 influences cell cycle arrest induced by 1,4-BQ. LncRNA-OBFC2A, Smad3 and Cyclin D1 as a set of biomarkers play important roles in benzene haematotoxicity.

5-Hydroxytryptamine (5-HT)-exacerbated DSS-induced colitis is associated with elevated NADPH oxidase expression in the colon.

AIM: This study investigated the impact of 5-hydroxytryptamine (5-HT) on the expression of NOXs in dextran sulfate sodium (DSS)-induced colitis in mice. METHODS: C57BL/6J (B6) mice at 6 to 8 weeks of age were treated with 5-HT, DSS, or DSS + 5-HT. After 6-day treatment, the severity of colitis, infiltration of leukocytes, and messenger RNA (mRNA) and/or protein levels of Nox1, Nox2, Nox4, and Duox2 were analyzed in the colon by real-time quantitative polymerase chain reaction (qPCR), immunohistochemistry (IHC), and Western blot analysis. The direct effect of 5-HT on NOX gene and protein expression in HT-29 colon cancer cells and in U-937 macrophage cells were determined by qPCR and Western blot analysis. RESULTS: Mice treated with 5-HT alone did not develop colitis, while those treated with 1.0% DSS or DSS + 5-HT had mild and severe colitis, respectively. All treated mice had more myeloperoxidase-positive cells in the colon compared with untreated control mice. Mice treated with 5-HT or DSS alone had increased Nox2 and Nox4 mRNA and protein levels in the colon determined by qPCR, IHC, and Western blot analysis. These two Nox expressions were even higher in mice treated with DSS + 5-HT, while the expression levels of epithelium-localized Nox1 and Duox2 tended to decrease. Additionally, mice treated with 5-HT alone had elevated Nox1 and Duox2 expression as shown by qPCR and IHC. However, these gene expressions were diminished in DSS + 5-HT-treated mice likely due to erosion of epithelium. Furthermore, 5-HT induced NOX1 and DUOX2 gene and protein expression in HT-29 colon cancer epithelial cells, whereas induced NOX2 and NOX4 gene and protein expression in U-937 cells. CONCLUSION: As 5-HT induced NOX1 and DUOX2 gene and protein expression in colon epithelial and HT-29 cells, NOX2 and NOX4 in the infiltrating leukocyte in mouse colon and in U-937 cells, the exacerbate colitis induced by combined 5-HT and DSS treatment might be relevant to increased NOX expression in mice colons.

Predictors of intention to smoke among junior high school students in Shanghai, China: an empirical test of the information-motivation-behavioral skills (IMB) model.

BACKGROUND: Adolescent smoking is a worldwide problem that is particularly severe in low- and middle-income countries. Many endogenous and environmental factors affect the intention to smoke, so a comprehensive model is needed to understand the significance and relationship of predictors. The study aimed to test the associations among information-motivation-behavioral skills (IMB) model constructs as predictors of intention to smoke in junior high school students in Shanghai, China. METHODS: We conducted a cross-sectional study of 16,500 junior high school students in Shanghai, China. Data on tobacco-related information, motivation, behavioral skills, and behaviors were collected from students. Structural equation model (SEM) was used to assess the IMB model. RESULTS: The mean age of participants was 13.8 years old (standard deviation = 1.02; range 11-17). The experimental smoking rate among junior high school students was 6.6% and 8.7% of the participants expected that they would be smokers in 5 years. The IMB model provided acceptable fit to the data (comparative fit index = 0.984, root mean square error of approximation = 0.04). Intention to smoke was predicted by behavioral skills (ß = 0.670, P < 0.001) and motivation (ß = 0.095, P<0.001) among junior high school students. CONCLUSION: The IMB model provides a good understanding of the predictors of intention to smoke and it suggests future interventions among junior high school students should focus on improving motivation and behavioral skills.