Heterogeneity of SARS-CoV-2 immune responses after the nationwide Omicron wave in China.

It remains unclear how previous infections and vaccinations influenced and shaped heterogeneous immune responses against Omicron and its variants in diverse populations in China. After the national wave of Omicron in early 2023, we evaluated serum levels of neutralizing antibodies (nAbs) against Omicron (B.1.1.529) and its variants (BA.5, BF.7, and CH1.1) in 33 COVID-19 convalescents and 40 uninfected vaccinees, using vesicular stomatitis virus-based pseudovirus neutralizing assay. In addition, we followed 34 Delta convalescent patients to compare their immune responses against Omicron before (late 2021) and after the Omicron wave (early 2023). NAbs at the acute phase of the disease were investigated in 50 Omicron inpatients, including 24 vaccinated and 26 unvaccinated patients. Among them, nasal mucosal IgA levels were measured in 42 subjects. Compared to vaccination, breakthrough infections significantly increased the breadth and magnitude of serum nAbs and mucosal IgA levels against Omicron variants. Exposure to Omicron but not Delta elicited stronger pan-Omicron responses. In Omicron inpatients, nAbs continued to rise as vaccination doses increased. However, in both vaccinees and convalescents, a fourth dose vaccination did not elicit higher nAbs against Omicron. Furthermore, nAbs against Omicron variants lasted longer than nAbs against WT SARS-CoV-2. Breakthrough infections of Omicron variants elicited specific immune responses against Omicron compared to vaccination and Delta infection. Although repeated vaccination revealed limited impacts on serum nAbs, populations at high risk of hospitalization may still benefit from continued vaccination.IMPORTANCEThe study described the specific humoral immunity against Omicron and its variants (BA.5, BF.7, and CH1.1) in diverse populations, including Delta-positive convalescent patients, Omicron-infected patients with a previous or current confirmed Delta infection, Omicron-positive patients, and healthy controls. In addition, we followed Delta convalescents for 1 year to evaluate the effect of a booster vaccine, breakthrough infection, and reinfection. Nasal mucosal IgA levels against SARS-CoV-2 were also examined. The findings of this study demonstrated the varied responses of individuals in different states following the outbreak of Omicron, highlighting the potential advantages of ongoing immunization for groups that are more vulnerable and have a greater likelihood of being hospitalized.

Identification of immune-associated biomarker for predicting lung adenocarcinoma: bioinformatics analysis and experiment verification of PTK6.

BACKGROUND: Abnormal expression of protein tyrosine kinase 6 (PTK6) has been proven to be involved in the development of gynecological tumors. However, its immune-related carcinogenic mechanism in other tumors remains unclear. OBJECTIVE: The aim of this study was to identify PTK6 as a novel prognostic biomarker in pan-cancer, especially in lung adenocarcinoma (LUAD), which is correlated with immune infiltration, and to clarify its clinicopathological and prognostic significance. METHODS: The prognostic value and immune relevance of PTK6 were investigated by using bio-informatics in this study. PTK6 expression was validated in vitro experiments (lung cancer cell lines PC9, NCI-H1975, and HCC827; human normal lung epithelial cells BEAS-2B). Western blot (WB) revealed the PTK6 protein expression in lung cancer cell lines. PTK6 expression was inhibited by Tilfrinib. Colony formation and the Cell Counting Kit-8 (CCK-8) assay were used to detect cell proliferation. The wound healing and trans-well were performed to analyze the cell migration capacity. Then flow cytometry was conducted to evaluate the cell apoptosis. Eventually, the relationship between PTK6 and immune checkpoints was examined. WB was used to estimate the PD-L1 expression at different Tilfrinib doses. RESULTS: PTK6 was an independent predictive factor for LUAD and was substantially expressed in LUAD. Pathological stage was significantly correlated with increased PTK6 expression. In accordance with survival analysis, poor survival rate in LUAD was associated with a high expression level of PTK6. Functional enrichment of the cell cycle and TGF-ß signaling pathway was demonstrated by KEGG and GSEA analysis. Moreover, PTK6 expression considerably associated with immune infiltration in LUAD, as determined by immune analysis. Thus, the result of vitro experiments indicated that cell proliferation and migration were inhibited by the elimination of PTK6. Additionally, PTK6 suppression induced cell apoptosis. Obviously, PD-L1 protein expression level up-regulated while PTK6 was suppressed. CONCLUSION: PTK6 has predictive value for LUAD prognosis, and could up regulated PD-L1.

T2T-YAO: A Telomere-to-telomere Assembled Diploid Reference Genome for Han Chinese.

Since its initial release in 2001, the human reference genome has undergone continuous improvement in quality, and the recently released telomere-to-telomere (T2T) version - T2T-CHM13 - reaches its highest level of continuity and accuracy after 20 years of effort by working on a simplified, nearly homozygous genome of a hydatidiform mole cell line. Here, to provide an authentic complete diploid human genome reference for the Han Chinese, the largest population in the world, we assembled the genome of a male Han Chinese individual, T2T-YAO, which includes T2T assemblies of all the 22 + X + M and 22 + Y chromosomes in both haploid. The quality of T2T-YAO is much better than all currently available diploid assemblies, and its haploid version, T2T-YAO-hp, generated by selecting the better assembly for each autosome, reaches the top quality of fewer than one error per 29.5 Mb, even higher than that of T2T-CHM13. Derived from an individual living in the aboriginal region of the Han population, T2T-YAO shows clear ancestry and potential genetic continuity from the ancient ancestors. Each haplotype of T2T-YAO possesses ∼ 330-Mb exclusive sequences, ∼ 3100 unique genes, and tens of thousands of nucleotide and structural variations as compared with CHM13, highlighting the necessity of a population-stratified reference genome. The construction of T2T-YAO, a truly accurate and authentic representative of the Chinese population, would enable precise delineation of genomic variations and advance our understandings in the hereditability of diseases and phenotypes, especially within the context of the unique variations of the Chinese population.

Corrigendum to "Comprehensive Humoral and Cellular Immune Responses to SARS-CoV-2 Variants in Diverse Chinese Population".

[This corrects the article DOI: 10.34133/2022/9873831.].

A Self-Assembly ICG Nanoparticle Potentiating Targeted Photothermal and Photodynamic Therapy in NSCLC.

In nonsmall cell lung cancers (NSCLC), near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has proven to be an efficient approach for locating pulmonary nodules and pulmonary sentinel lymph nodes. However, due to a lack of tumor selectivity, ICG's use as a photosensitizer for photothermal therapy (PTT) and photodynamic therapy (PDT) is restricted. In the current study, we aimed to develop a type of high-performance NIR nanoparticle formulated with ICG to enhance its targeted efficacy and tumor specificity on NSCLC. An ICG-osimertinib nanoparticle (ICG-Osi) was self-assembled through π-π stacking, with a size of 276 nm and a surface charge of -7.4 mV. The NIR visibility and epidermal growth factor receptor (EGFR) targetability of the ICG-Osi was confirmed by its binding efficiency to EGFR-expressing NSCLC cells in vitro and in vivo, regardless of EGFR mutation status. The targeted effect was further confirmed in mouse xenograft models and showed an extended tumor retention time (>96 h). We demonstrated a significantly enhanced hyperthermia effect and a retained reactive oxygen species (ROS) generating ability of ICG-Osi, resulting in a 2-fold higher cell death rate than ICG alone. The ICG-Osi down-regulated GPX4 and p62 expression while up-regulating caspase-3 and beclin1 expression in NSCLC cells, indicating a complex network of cell death-related proteins. Considering the merits of simple assembly, EGFR binding efficacy, improved hyperthermia effect, and efficient cancer cell suppression, the ICG-Osi exhibits great potential for clinical application in EGFR-expressing NSCLC therapy.

Comprehensive Humoral and Cellular Immune Responses to SARS-CoV-2 Variants in Diverse Chinese Population.

The SARS-CoV-2 variants have been emerging and have made great challenges to current vaccine and pandemic control strategies. It is urgent to understand the current immune status of various Chinese populations given that the preexisting immunity has been established by national vaccination or exposure to past variants. Using sera from 85 individuals (including 21 convalescents of natural infection, 15 cases which suffered a breakthrough infection after being fully vaccinated, and 49 healthy vaccinees), we showed significantly enhanced neutralizing activities against SRAS-CoV-2 variants in convalescent sera, especially those who had been fully vaccinated. The neutralizing antibodies against Omicron were detectable in 75% of convalescents and 44.9% of healthy vaccinees (p = 0.006), with a GMT of 289.5, 180.9-463.3, and 42.6, 31.3-59, respectively. However, the neutralizing activities were weaker in young convalescents (aged < 18 y), with a detectable rate of 50% and a GMT of 46.4 against Omicron. We also examined and found no pan-sarbecovirus neutralizing activities in vaccinated SARS-CoV-1 survivors. A booster dose could further increase the breadth and magnitude of neutralization against WT and variants of concern (VOCs) to different degrees. In addition, we showed that COVID-19-inactivated vaccines can elicit Omicron-specific T-cell responses. The positive rates of ELISpot reactions were 26.7% (4/15) and 43.8% (7/16) in the full vaccination group and the booster vaccination group, respectively, although without statistically significant difference. The neutralizing antibody titers declined while T-cell responses remain consistent over 6 months. These findings will inform the optimization of public health vaccination and intervention strategies to protect diverse populations against SARS-CoV-2 variants. Advances. Breakthrough infection significantly boosted neutralizing activities against SARS-CoV-2 variants as compared to booster immunization with inactivated vaccine. Vaccine-induced virus-specific T-cell immunity, on the other hand, may compensate for the shortfall. Furthermore, the public health system should target the most vulnerable group due to a poorer protective serological response in both infected and vaccinated adolescents.