Extended SARS-CoV-2 RBD booster vaccination induces humoral and cellular immune tolerance in mice.

The repetitive applications of vaccine boosters have been brought up in face of continuous emergence of SARS-CoV-2 variants with neutralization escape mutations, but their protective efficacy and potential adverse effects remain largely unknown. Here, we compared the humoral and cellular immune responses of an extended course of recombinant receptor binding domain (RBD) vaccine boosters with those from conventional immunization strategy in a Balb/c mice model. Multiple vaccine boosters after the conventional vaccination course significantly decreased RBD-specific antibody titers and serum neutralizing efficacy against the Delta and Omicron variants, and profoundly impaired CD4+ and CD8+T cell activation and increased PD-1 and LAG-3 expressions in these T cells. Mechanistically, we confirmed that extended vaccination with RBD boosters overturned the protective immune memories by promoting adaptive immune tolerance. Our findings demonstrate potential risks with the continuous use of SARS-CoV-2 vaccine boosters, providing immediate implications for the global COVID-19 vaccination enhancement strategies.

KDM6B promotes ESCC cell proliferation and metastasis by facilitating C/EBPß transcription.

BACKGROUND: As an H3K27me3 demethylase and counteracts polycomb-mediated transcription repression, KDM6B has been implicated in the development and malignant progression in various types of cancers. However, its potential roles in esophageal squamous cell carcinoma (ESCC) have not been explored. METHODS: The expression of KDM6B in human ESCC tissues and cell lines was examined using RT-qPCR, immunohistochemical staining and immunoblotting. The effects of KDM6B on the proliferation and metastasis of ESCC were examined using in vitro and in vivo functional tests. RNA-seq and ChIP-seq assay were used to demonstrate the molecular biological mechanism of KDM6B in ESCC. RESULTS: We show that the expression level of KDM6B increased significantly in patients with lymph node metastasis. Furthermore, we confirmed that KDM6B knockdown reduces proliferation and metastasis of ESCC cells, while KDM6B overexpression has the opposite effects. Mechanistically, KDM6B regulates TNFA_SIGNALING_VIA_NFκB signalling pathways, and H3K27me3 binds to the promoter region of C/EBPß, leading to the promotion of C/EBPß transcription. Besides, we show that GSK-J4, a chemical inhibitor of KDM6B, markedly inhibits proliferation and metastasis of ESCC cells. CONCLUSIONS: The present study demonstrated that KDM6B promotes ESCC progression by increasing the transcriptional activity of C/EBPß depending on its H3K27 demethylase activity.

Clinical spectrum of intra-abdominal abscesses in children admitted to the pediatric emergency department.

BACKGROUND: To analyze clinical spectrum of intra-abdominal abscesses in children and find helpful clinical parameters could aid physicians in earlier detection and differential diagnosis. METHODS: From 2004 to 2011, we retrospectively analyzed 66 pediatric patients, aged 18 years or younger with intra-abdominal abscesses. The data were obtained and studied: demographics, clinical presentations, etiologies, laboratory tests, microbiology, imaging studies, treatment modalities, complications and long-term outcomes. RESULTS: There were 66 patients (mean age, 9.27 ± 4.16 years) diagnosed as intra-abdominal abscesses. The two most common presented symptoms were fever and abdominal pain (90.9%; 78.8%, respectively). Most patients presented with leukocytosis (81.8%) and elevated C-reactive protein (CRP) levels (95.5%). In patients with abscesses in solid organs, urine white blood cell counts, nitrate and leukocyte esterase were all significant parameters (all P < 0.05), and urine pH and specific gravity were both lower than those in non-solid organs (P = 0.026; P = 0.043, respectively). Escherichia coli (E. coli) was the most common organism cultured from renal abscess. Streptococcus viridans was the most common organism cultured from liver abscess. Moreover, the two most predominant bacteria in periappendical and intraperitoneal abscesses were E. coli and Bacteroides fragilis. CONCLUSIONS: We suggest that primary physicians should keep this disease in mind when children present with predisposing risk factors, fever, abdominal pain, leukocytosis and elevated CRP level. Besides, we recommend the urinary analysis or ultrasonography (US) is valuable in patients with fever and abdominal pain.

IL-6 and IL-8 secreted by tumour cells impair the function of NK cells via the STAT3 pathway in oesophageal squamous cell carcinoma.

BACKGROUND: Recurrence and metastasis are the leading causes of tumour-related death in patients with oesophageal squamous cell carcinoma (ESCC). Tumour-infiltrating natural killer cells (NK cells) display powerful cytotoxicity to tumour cells and play a pivotal role in tumour therapy. However, the phenotype and functional regulation of NK cells in oesophageal squamous cell carcinoma (ESCC) remains largely unknown. METHODS: Single cell suspensions from blood and tissue samples were isolated by physical dissociation and filtering through a 70 µm cell strainer. Flow cytometry was applied to profile the activity and function of NK cells, and an antibody chip experiment was used to identify and quantitate cytokine levels. We studied IL-6 and IL-8 function in primary oesophageal squamous carcinoma and NK cell co-cultures in vitro and by a xenograft tumour model in vivo. Western blotting was used to quantitate STAT3 (signal transducer and activator of transcription 3) and p-STAT3 levels. Finally, we performed an IHC array to analyse IL-6/IL-8 (interleukin 6/interleukin 8) expression in 103 pairs of tumours and matched adjacent tissues of patients with ESCC to elucidate the correlation between IL-6 or IL-8 and clinical characteristics. RESULTS: The percentages of NK cells in both peripheral blood and tumour tissues from patients with ESCC were significantly increased in comparison with those in the controls and correlated with the clinical characteristics. Furthermore, the decrease in activating receptors and increase in inhibitory receptors on the surface of tumour-infiltrating NK cells was confirmed by flow cytometry. The level of granzyme B, the effector molecule of tumour-infiltrating NK cells, was also decreased. Mechanistically, primary ESCC cells activated the STAT3 signalling pathway on NK cells through IL-6 and IL-8 secretion, leading to the downregulation of activating receptors (NKp30 and NKG2D) on the surface of NK cells. An ex vivo study showed that blockade of STAT3 attenuated the IL-6/IL-8-mediated impairment of NK cell function. Moreover, the expression of IL-6 or IL-8 in tumour tissues was validated by immunohistochemistry to be positively correlated with tumour progression and poor survival, respectively. CONCLUSIONS: Tumour cell-secreted IL-6 and IL-8 impair the activity and function of NK cells via STAT3 signalling and contribute to oesophageal squamous cell carcinoma malignancy.

[Effect of Epithelial-to-mesenchymal Transition on Biological Activity of NK Cells in Esophageal Squamous Cell Carcinoma].

OBJECTIVE: To investigate the effect of epithelial-mesenchymal transition (EMT) on biological activity of natural killer (NK) cells in esophageal squamous cell carcinoma (ESCC). METHODS: Western blot selected EMT EC9706 and non EMT KYSE150 from six esophageal cancer cell lines. NK cells were collected from 10 cases of healthy volunteers. According to different co-culture conditions, the medium was divided into 1640 normal medium stimulus-NK group (NC group), EC9706 cell supernatant stimulus-NK group (EC9706 group) and KYSE150 cell supernatant stimulus-NK group (KYSE150 group). The expression of NK cells surface/intracellular molecules was detected by flow cytometry after co-culture of NK cells with different conditioned medium for 72 h. 10 ng/mL transforming growth factor-ß (TGF-ß) treated KYSE150 cell line for 7 d to induce EMT. KYSE150 EMT and KYSE150 supernatant were collected and co-cultured with NK cells, respectively. 72 h later, flow cytometry was used to detect the expression of surface/intracellular molecules of NK cells, degranulation ability of CD107a, killing effect of target cell K562, proliferation and apoptosis of NK cells. RESULTS: Two EMT-treated and four non-EMT-treated esophageal squamous cell carcinoma lines were selected from the six strains, and one EC9706 and one KYSE150 respectively were selected for subsequent experiments. The purity of NK cells was more than 90% and Tcells <1%. After the supernatant of esophageal squamous cell carcinoma cells was stimulated, the surface activation type and inhibitory type receptors of NK cells in the three groups were stimulated. The effector molecule results showed that: compared with NC group and KYSE150 group, the expressions of activated type receptors NKP30, NKG2D and NKP44 in EC9706 group were decreased, and the release of granulozyme was decreased ( P<0.05). Expressions of inhibitory receptor NKG2A and CD158b increased ( P<0.05). NKP46, CD226, CD16 expressions and perforin release showed no statistically significant difference among the three groups. Compared with KYSE150 supernatant stimulation, the expressions of activated receptors NKP30, NKG2D and NKP44 decreased after KYSE150 EMT supernatant stimulation, and perforin release decreased. The degranulation of CD107a and the killing effect of target cell K562 were decreased, and the proliferation index of NK cell Ki67 was decreased ( P<0.05). Expressions of inhibitory receptor NKG2A and CD158b increased ( P<0.05). The expressions of NKP46, CD226 and CD16, granulozyme release and apoptosis of NK cells were not statistically significant. CONCLUSION: EMT of esophageal cancer cells can escape the immune surveillance by inhibit the activity of NK cells and reduce the release of effective molecules.

Hypertension and chronic kidney disease affect long-term outcomes in patients with stable coronary artery disease receiving percutaneous coronary intervention.

Percutaneous coronary intervention (PCI) is commonly used for patients with coronary artery disease (CAD). However, the effects of chronic kidney disease (CKD) and hypertension (HT) on long-term outcomes in patients with stable CAD receiving PCI are still unclear. A total of 1,676 patients treated with PCI were prospectively enrolled and divided into 4 groups according to the presence or absence of HT or CKD. General characteristics, clinical medications, risk factors, angiographic findings, and long-term outcomes were analyzed. Patients with CKD had the highest rate of all-cause and cardiovascular (CV) mortality (both P < 0.01). Patients with CKD alone had the lowest event-free rate of all-cause and CV deaths (both P < 0.001). Based on Cox proportional hazard model, patients with CKD alone had the highest risk of all-cause death (HR:2.86, 95% CI:1.73-4.75) and CV death (HR: 3.57,95% CI:2.01-6.33); while patients with both CKD and HT had the highest risk of repeat PCI (HR: 1.42, 95% CI:1.09-1.85).We found that in stable CAD patients after undergoing PCI, those with CKD alone had the highest long-term mortality. Comorbid CKD appears to increase risk in patient with HT, whereas comorbid HT doesn't seem to increase risk in patients with CKD.

Predictive power of a single body temperature at different cutoff values for neonates in the nursery transferring to special care nursery.

The aim of this study was to identify the clinical parameters indicative of serious etiology of neonatal hyperthermia and to determine the appropriate cutoff value of body temperature (BT) for predicting the need to transfer the newborn to the special care (SC) nursery.The nursery records of newborns diagnosed with hyperthermia between 2007 and 2013 were retrospectively reviewed. The clinical characteristics of newborns with hyperthermia remained in the nursery were compared with those transferred to the SC nursery. In addition, the receiver operating characteristic analysis was used to determine the appropriate cutoff BT for predicting further septic workup in the SC nursery.Among the 92 newborns with hyperthermia evaluated, 30 (32.6%) were transferred to the SC nursery and 62 (67.4%) remained in the nursery. Clinical characteristics associated with transfer to the SC nursery included the highest BT, BT at first measurement during hyperthermia, frequency of hyperthermia, duration of hyperthermia, irritable crying, decreased appetite, poor activity, vomiting with abdominal distension, tachypnea, and tachycardia (all P < .05). BT for predicting the need for transferring newborns with hyperthermia to the SC nursery had an area under the curve of 0.976 (P < .001). A BT of 38 °C was determined as the optimal cutoff value for predicting the need to monitoring for suspicious clinical symptoms (sensitivity (Sn), 93%; specificity (Sp), 87%). Furthermore, BT≥38.2 °C (Sn, 70%; Sp 100%) and BT≤37.8 °C (Sn, 100%; Sp, 61%) respectively were determined as the cutoff values for transferring newborns to the SC nursery or allowing them to remain in the regular nursery.Our results suggest a BT of 38 °C represents the optimal cutoff indicating newborns for close monitoring for suspicious clinical presentations including irritable crying, decreased appetite, poor activity, vomiting with abdominal distension, tachypnea, and tachycardia. Newborns with BT < 37.8 °C may remain in the nursery but should be transferred to the SC nursery for septic workup and empiric antibiotics if the BT is above 38.2 °C.