Clinical features and prognosis of ANCA-associated vasculitis patients who were double-seropositive for myeloperoxidase-ANCA and proteinase 3-ANCA.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) patients with dual positivity for proteinase 3-ANCA (PR3-ANCA) and myeloperoxidase-ANCA (MPO-ANCA) are uncommon. We aimed to investigate these idiopathic double-positive AAV patients' clinical features, histological characteristics, and prognosis. We reviewed all the electronic medical records of patients diagnosed with AAV to obtain clinical data and renal histological information from January 2010 to December 2020 in a large center in China. Patients were assigned to the MPO-AAV group or PR3-AAV group or idiopathic double-positive AAV group by ANCA specificity. We explored features of idiopathic double-positive AAV. Of the 340 patients who fulfilled the study inclusion criteria, 159 (46.76%) were female, with a mean age of 58.41 years at the time of AAV diagnosis. Similar to MPO-AAV, idiopathic double-positive AAV patients were older and had more severe anemia, lower Birmingham Vasculitis Activity Score (BVAS) and C-reactive protein (CRP) levels, less ear, nose, and throat (ENT) involvement, higher initial serum creatinine and a lower estimated glomerular filtration rate (eGFR) when compared with PR3-AAV (P < 0.05). The proportion of normal glomeruli of idiopathic double-positive AAV was the lowest among the three groups (P < 0.05). The idiopathic double-positive AAV patients had the worst remission rate (58.8%) among the three groups (P < 0.05). The relapse rate of double-positive AAV (40.0%) was comparable with PR3-AAV (44.8%) (P > 0.05). Although there was a trend toward a higher relapse rate of idiopathic double-positive AAV (40.0%) compared with MPO-AAV (23.5%), this did not reach statistical significance (P > 0.05). The proportion of patients who progressed to ESRD was 47.1% and 44.4% in the idiopathic double-positive AAV group and MPO-AAV group respectively, without statistical significance. Long-term patient survival also varied among the three groups (P < 0.05). Idiopathic double-positive AAV is a rare clinical entity with hybrid features of MPO-AAV and PR3-AAV. MPO-AAV is the "dominant" phenotype in idiopathic double-positive AAV.

The Influence of Cross-Reactive T Cells in COVID-19.

Memory T cells form from the adaptive immune response to historic infections or vaccinations. Some memory T cells have the potential to recognise unrelated pathogens like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and generate cross-reactive immune responses. Notably, such T cell cross-reactivity has been observed between SARS-CoV-2 and other human coronaviruses. T cell cross-reactivity has also been observed between SARS-CoV-2 variants from unrelated microbes and unrelated vaccinations against influenza A, tuberculosis and measles, mumps and rubella. Extensive research and debate is underway to understand the mechanism and role of T cell cross-reactivity and how it relates to Coronavirus disease 2019 (COVID-19) outcomes. Here, we review the evidence for the ability of pre-existing memory T cells to cross-react with SARS-CoV-2. We discuss the latest findings on the impact of T cell cross-reactivity and the extent to which it can cross-protect from COVID-19.

Smith-specific regulatory T cells halt the progression of lupus nephritis.

Antigen-specific regulatory T cells (Tregs) suppress pathogenic autoreactivity and are potential therapeutic candidates for autoimmune diseases such as systemic lupus erythematosus (SLE). Lupus nephritis is associated with autoreactivity to the Smith (Sm) autoantigen and the human leucocyte antigen (HLA)-DR15 haplotype; hence, we investigated the potential of Sm-specific Tregs (Sm-Tregs) to suppress disease. Here we identify a HLA-DR15 restricted immunodominant Sm T cell epitope using biophysical affinity binding assays, then identify high-affinity Sm-specific T cell receptors (TCRs) using high-throughput single-cell sequencing. Using lentiviral vectors, we transduce our lead Sm-specific TCR into Tregs derived from patients with SLE who are anti-Sm and HLA-DR15 positive. Compared with polyclonal mock-transduced Tregs, Sm-Tregs potently suppress Sm-specific pro-inflammatory responses in vitro and suppress disease progression in a humanized mouse model of lupus nephritis. These results show that Sm-Tregs are a promising therapy for SLE.

Epithelially Restricted Interferon Epsilon Protects Against Colitis.

BACKGROUND & AIMS: Type I interferon (T1IFN) signalling is crucial for maintaining intestinal homeostasis. We previously found that the novel T1IFN, IFNε, is highly expressed by epithelial cells of the female reproductive tract, where it protects against pathogens. Its function has not been studied in the intestine. We hypothesize that IFNε is important in maintaining intestinal homeostasis. METHODS: We characterized IFNε expression in mouse and human intestine by immunostaining and studied its function in the dextran sulfate sodium (DSS) colitis model using both genetic knockouts and neutralizing antibody. RESULTS: We demonstrate that IFNε is expressed in human and mouse intestinal epithelium, and expression is lost in inflammation. Furthermore, we show that IFNε limits intestinal inflammation in mouse models. Regulatory T cell (Treg) frequencies were paradoxically decreased in DSS-treated IFNε-/- mice, suggesting a role for IFNε in maintaining the intestinal Treg compartment. Colitis was ameliorated by transfer of wild-type Tregs into IFNε-/- mice. This demonstrates that IFNε supports intestinal Treg function. CONCLUSIONS: Overall, we have shown IFNε expression in intestinal epithelium and its critical role in gut homeostasis. Given its known role in the female reproductive tract, we now show IFNε has a protective role across multiple mucosal surfaces.

The interplay between the microbiota, diet and T regulatory cells in the preservation of the gut barrier in inflammatory bowel disease.

Inflammatory bowel disease (IBD) is becoming more common in the Western world due to changes in diet-related microbial dysbiosis, genetics and lifestyle. Incidences of gut permeability can predate IBD and continued gut barrier disruptions increase the exposure of bacterial antigens to the immune system thereby perpetuating chronic inflammation. Currently, most of the approved IBD therapies target individual pro-inflammatory cytokines and pathways. However, they fail in approximately 50% of patients due to their inability to overcome the redundant pro inflammatory immune responses. There is increasing interest in the therapeutic potential of T regulatory cells (Tregs) in inflammatory conditions due to their widespread capability to dampen inflammation, promote tolerance of intestinal bacteria, facilitate healing of the mucosal barrier and ability to be engineered for more targeted therapy. Intestinal Treg populations are inherently shaped by dietary molecules and gut microbiota-derived metabolites. Thus, understanding how these molecules influence Treg-mediated preservation of the intestinal barrier will provide insights into immune tolerance-mediated mucosal homeostasis. This review comprehensively explores the interplay between diet, gut microbiota, and immune system in influencing the intestinal barrier function to attenuate the progression of colitis.

Single-cell transcriptomics uncover hub genes and cell-cell crosstalk in patients with hypertensive nephropathy.

Hypertensive nephropathy (HTN) is one of the leading causes of end-stage renal disease, yet the molecular mechanisms are still unknown. To explore novel mechanisms and gene targets for HTN, the gene expression profiles of renal biopsy samples obtained from 2 healthy living donor controls and 5 HTN patients were determined by single-cell RNA sequencing. Key hub genes expression were validated by the Nephroseq v5 platform. The HTN endothelium upregulated cellular adhesion genes (ICAM2 and CEACAM1), inflammatory genes (ETS2 and IFI6) and apoptosis related genes (CNN3). Proximal tubules in HTN highly expressed hub genes including BBOX1, TPM1, TMSB10, SDC4, and NUP58, which might be potential novel targets for proximal tubular injury. The upregulated genes in tubules of HTN were mainly participating in inflammatory signatures including IFN-γ signature, NF-κB signaling, IL-12 signaling and Wnt signaling pathway. Receptor-ligand interaction analysis indicated potential cell-cell crosstalk between endothelial cells or mesangial cells with other renal resident cells in HTN. Together, our data identify a distinct cell-specific gene expression profile, pathogenic inflammatory signaling and potential cell-cell communications between endothelial cells or mesangial cells with other renal resident cells in HTN. These findings may provide a promising novel landscape for mechanisms and treatment of human HTN.

Development of a radiomics nomogram to predict the treatment resistance of Chinese MPO-AAV patients with lung involvement: a two-center study.

Background: Previous studies from our group and other investigators have shown that lung involvement is one of the independent predictors for treatment resistance in patients with myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-AAV). However, it is unclear which image features of lung involvement can predict the therapeutic response in MPO-AAV patients, which is vital in decision-making for these patients. Our aim was to develop and validate a radiomics nomogram to predict treatment resistance of Chinese MPO-AAV patients based on low-dose multiple slices computed tomography (MSCT) of the involved lung with cohorts from two centers. Methods: A total of 151 MPO-AAV patients with lung involvement (MPO-AAV-LI) from two centers were enrolled. Two different models (Model 1: radiomics signature; Model 2: radiomics nomogram) were built based on the clinical and MSCT data to predict the treatment resistance of MPO-AAV with lung involvement in training and test cohorts. The performance of the models was assessed using the area under the curve (AUC). The better model was further validated. A nomogram was constructed and evaluated by DCA and calibration curves, which further tested in all enrolled data and compared with the other model. Results: Model 2 had a higher predicting ability than Model 1 both in training (AUC: 0.948 vs. 0.824; p = 0.039) and test cohorts (AUC: 0.913 vs. 0.898; p = 0.043). As a better model, Model 2 obtained an excellent predictive performance (AUC: 0.929; 95% CI: 0.827-1.000) in the validation cohort. The DCA curve demonstrated that Model 2 was clinically feasible. The calibration curves of Model 2 closely aligned with the true treatment resistance rate in the training (p = 0.28) and test sets (p = 0.70). In addition, the predictive performance of Model 2 (AUC: 0.929; 95% CI: 0.875-0.964) was superior to Model 1 (AUC: 0.862; 95% CI: 0.796-0.913) and serum creatinine (AUC: 0.867; 95% CI: 0.802-0.917) in all patients (all p< 0.05). Conclusion: The radiomics nomogram (Model 2) is a useful, non-invasive tool for predicting the treatment resistance of MPO-AAV patients with lung involvement, which might aid in individualizing treatment decisions.

Sex disparities in clinicopathological features and outcomes of patients with myeloperoxidase-ANCA-associated vasculitis: a retrospective study of 366 cases in a single Chinese center.

There are a few studies that reported sex disparities in clinical features, pathological features and outcomes among ANCA-associated vasculitis (AAV) patients, but studies focusing on sex-specific differences of myeloperoxidase (MPO)-AAV patients are scarce. Therefore, the purpose of this study was to analyze sex differences in clinicopathological features and outcomes of MPO-AAV. Patients diagnosed with MPO-AAV in Xiangya Hospital from January 2010 to June 2021 were included in the study and separated into female and male groups. The differences in clinical manifestations, laboratory parameters, pathological features and prognosis between the two groups were retrospectively analyzed. Three hundred and sixty-six patients were included and divided into female group (n = 176) and male group (n = 190). The age of the male group was 62.41 ± 10.49 years, significantly higher than that of the female group (58.69 ± 16.39, p = 0.011). Compared with the female group, the male group had a shorter duration of disease, higher levels of hemoglobin, eosinophil count, proteinuria, serum C4, and lower levels of serum globulin, serum IgG and serum IgM (p < 0.05). No significant differences in kidney pathological features were observed between the two groups. During a median follow-up of 37.6 months, there was no significant difference in renal survival and patient survival between the two groups, but male patients had a worse composite outcome of renal and patient survival compared with the female patients (p = 0.044). This study found that male patients with MPO-AAV had a higher age of onset, shorter duration of disease, higher levels of hemoglobin, eosinophil count, proteinuria, serum C4, and lower levels of serum globulin, serum IgG and serum IgM. Male patients fared worse than female patients in terms of the composite outcome of renal and patient survival.

Engineering Cell Lines for Specific Human Leukocyte Antigen Presentation.

Epitope-specific immunotherapies have enabled the targeted treatment of a variety of diseases, ranging from cancer, infection, and autoimmune disorders. For CD8+ T cell-based therapies, the precise identification of immunogenic peptides presented by human leukocyte antigen (HLA) class I is essential which can be achieved by immunopeptidomics. Here, using lentivirus-mediated transduction and cell sorting approaches, we present a method to engineer a cell line that does not express its native HLA but instead expresses an HLA of interest (in this instance HLA-A*02:01). This technique can be used to elucidate the immunopeptidome of cell lines expressing different HLAs.

Single-cell RNA sequencing reveals the transcriptomic landscape of kidneys in patients with ischemic acute kidney injury.

BACKGROUND: Ischemic acute kidney injury (AKI) is a common syndrome associated with considerable mortality and healthcare costs. Up to now, the underlying pathogenesis of ischemic AKI remains incompletely understood, and specific strategies for early diagnosis and treatment of ischemic AKI are still lacking. Here, this study aimed to define the transcriptomic landscape of AKI patients through single-cell RNA sequencing (scRNA-seq) analysis in kidneys. METHODS: In this study, scRNA-seq technology was applied to kidneys from two ischemic AKI patients, and three human public scRNA-seq datasets were collected as controls. Differentially expressed genes (DEGs) and cell clusters of kidneys were determined. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, as well as the ligand-receptor interaction between cells, were performed. We also validated several DEGs expression in kidneys from human ischemic AKI and ischemia/reperfusion (I/R) injury induced AKI mice through immunohistochemistry staining. RESULTS: 15 distinct cell clusters were determined in kidney from subjects of ischemic AKI and control. The injured proximal tubules (PT) displayed a proapoptotic and proinflammatory phenotype. PT cells of ischemic AKI had up-regulation of novel pro-apoptotic genes including USP47 , RASSF4 , EBAG9 , IER3 , SASH1 , SEPTIN7 , and NUB1 , which have not been reported in ischemic AKI previously. Several hub genes were validated in kidneys from human AKI and renal I/R injury mice, respectively. Furthermore, PT highly expressed DEGs enriched in endoplasmic reticulum stress, autophagy, and retinoic acid-inducible gene I (RIG-I) signaling. DEGs overexpressed in other tubular cells were primarily enriched in nucleotide-binding and oligomerization domain (NOD)-like receptor signaling, estrogen signaling, interleukin (IL)-12 signaling, and IL-17 signaling. Overexpressed genes in kidney-resident immune cells including macrophages, natural killer T (NKT) cells, monocytes, and dendritic cells were associated with leukocyte activation, chemotaxis, cell adhesion, and complement activation. In addition, the ligand-receptor interactions analysis revealed prominent communications between macrophages and monocytes with other cells in the process of ischemic AKI. CONCLUSION: Together, this study reveals distinct cell-specific transcriptomic atlas of kidney in ischemic AKI patients, altered signaling pathways, and potential cell-cell crosstalk in the development of AKI. These data reveal new insights into the pathogenesis and potential therapeutic strategies in ischemic AKI.

The effect of discontinuation of maintenance therapy in Chinese patients with MPO-ANCA associated vasculitis who were in long-term stable remission.

There is a consensus that maintenance therapy should be used to prevent relapse of myeloperoxidase-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-AAV), but there is a debate about the optimal duration of maintenance therapy. Therefore, the purpose of this study was to determine whether discontinuation of maintenance therapy in MPO-AAV patients who were in long-term stable remission affects relapse, renal survival and patient survival. Seventy-nine patients with MPO-AAV diagnosed at Xiangya hospital from June 2010 to June 2019 who were in stable remission for at least 18 months following maintenance therapy were included. Patient records were retrospectively reviewed, and based on whether patients discontinued maintenance therapy 18 months after commencing maintenance therapy, patients were assigned into either the withdrawal group (n = 26) or maintenance group (n = 53). The endpoint was the percentage of relapse, relapse-free survival, renal survival and patient survival during follow-up. Ten relapses (38.5%) occurred in the withdrawal group (n = 26) and 8 relapses (15.1%) occurred in the maintenance group (n = 53) (p = 0.020). Compared to the withdrawal group, the maintenance group had similar relapse-free survival (log-rank test p = 0.099). But maintenance group had a better renal survival (p = 0.035), with no difference in patient survival or adverse events. This study suggests that discontinuing maintenance therapy at 18 months following induction of sustained remission leads to a significant increase in the percentage of relapse, and decreases renal survival in patients with MPO-AAV, but does not decrease relapse-free survival or patient survival.

Coexistence of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and IgA nephropathy.

Co-occurrence of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and IgA nephropathy (IgAN) is extremely uncommon. To date, only a few case reports have described such patients. Here, we describe the clinical presentation, pathologic features, treatment response, and outcome data of five patients with the rare form of co-existing AAV and IgAN and compared the characteristics of these patients to AAV patients with pauci-immune glomerulonephritis (n = 10) and IgAN patients (n = 10) that were selected as controls by stratified random sampling. In addition, we summarize all the previously reported cases of AAV and IgAN. In total, including the current study, 16 AAV/IgAN overlap cases were reported. Our five patients with the coexistence of AAV and IgAN were younger than the ten AAV patients with pauci-immune glomerulonephritis (22.6 ± 8.2 years versus 48.9 ± 15.7 years, respectively, P = 0.004). Histologically, they had a significantly lower percentage of glomeruli with fibrous crescents compared with AAV patients (0.0% versus 4.0%, P = 0.038). Compared with ten IgAN patients, our five AAV/IgAN patients had higher levels of ESR (P = 0.032) and CRP (P = 0.031). After accepting treatment with a combination of steroid and immunosuppressants, all patients showed a positive response to therapy, except for one patient in our cohort and another previously reported patient. We described the clinical presentation, pathologic features, treatment response, and outcome data of five patients with overlapping AAV and IgAN. They had mild glomerular pathological lesions and a positive response to aggressive immunosuppressive therapy. They were quite similar to pauci-immune AAV patients in clinical features, except for younger age. They had a lower percentage of glomeruli with fibrous crescents compared with AAV patients. In contrast to IgAN patients, they had higher levels of ESR and CRP. The mechanism of the coexistence of IgAN and AAV needs further study.

Clinical features and prognosis of MPO-ANCA and anti-GBM double-seropositive patients.

Background: Several lines of evidence implicate that there are distinct differences between patients with myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA) and anti-glomerular basement membrane (GBM) antibody double-seropositive patients (DPPs) and single-positive patients. Hence, we conducted a retrospective study from a single center in China to analyze the clinical and pathological features, and prognosis of DPPs. Methods: 109 patients with MPO-ANCA-associated vasculitis (MPO-AAV), 20 DPPs and 23 patients diagnosed with anti-GBM disease from a large center in China were included in this study. The ratio of patients with renal biopsy in three groups were 100%, 50% and 100%, respectively. Their clinical and pathological characteristics, and outcomes were analyzed. The intensity of immune deposits in the kidney at diagnosis was detected by immunofluorescence (IF). Furthermore, multivariate Cox hazard model analysis was used to assess the clinical and histological predictors of end-stage renal disease (ESRD) and death for DPPs. Results: In our study, we found that patients in the DPPs group were older than the other two groups (p = 0.007, MPO-AAV vs. DPPs; p < 0.001, DPPs vs. anti-GBM). The DPPs group had a higher value of serum creatinine (p = 0.041) and lower estimated glomerular filtration rate (eGFR) (p = 0.032) compared with MPO-AAV patients. On the contrary, the DPPs group had a lower serum creatinine (p = 0.003) compared with patients with anti-GBM group. The proportion of patients with cardiac system involvement in the DPPs group was higher than anti-GBM patients (p = 0.014). Cellular crescents could be generally observed in renal biopsy of DPPs and patients with anti-GBM glomerulonephritis. In addition, Bowman's capsule rupture was more common in DPPs than MPO-AAV patients (p = 0.001). MPO-AAV had a better renal and overall survival outcome than DPPs (p < 0.001). There was no significant difference of renal and overall survival outcome between DPPs and patients with anti-GBM disease. The incidence of ESRD in DPPs was negatively associated with lymphocyte count (HR 0.153, 95% CI 0.027 to 0.872, p = 0.034) and eGFR (HR 0.847, 95% CI 0.726 to 0.989, p = 0.036). Elevated serum creatinine was confirmed as a risk factor of both renal (HR 1.003, 95% CI 1.000 to 1.005, p = 0.019) and patient survival in DPPs (HR1.461, 95% CI 1.050 to 2.033, p = 0.024). Conclusion: In summary, compared with anti-GBM disease, DPPs tended to involve multi-organ damage rather than limited to the kidney. It is highlighted that serologic DPPs have a worse renal and patient prognosis than MPO-AAV. Moreover, we found that the risk factors of renal survival of DPPs include low lymphocyte count, elevated serum creatinine and reduced eGFR, and serum creatinine can predict patient survival.

Intrarenal Single-Cell Sequencing of Hepatitis B Virus Associated Membranous Nephropathy.

To date, the pathogenesis of hepatitis B virus (HBV)-associated membranous nephropathy (MN) remains elusive. This study aimed to decipher the etiopathogenesis of HBV-associated MN by performing single-cell RNA sequencing (scRNA-seq) of kidney biopsy specimens from a patient with HBV-associated MN and two healthy individuals. We generated 4,114 intrarenal single-cell transcriptomes from the HBV-associated MN patient by scRNA-seq. Compared to healthy individuals, podocytes in the HBV-associated MN patient showed an increased expression of extracellular matrix formation-related genes, including HSPA5, CTGF, and EDIL3. Kidney endothelial cells (ECs) in the HBV-associated MN were enriched in inflammatory pathways, including NF-kappa B signaling, IL-17 signaling, TNF signaling and NOD-like receptor signaling. Gene ontology (GO) functional enrichment analysis and Gene Set Variation Analysis (GSVA) further revealed that differentially expressed genes (DEGs) of ECs from the HBV-associated MN patients were enriched in apoptotic signaling pathway, response to cytokine and leukocyte cell-cell adhesion. The up-regulated DEGs in glomerular ECs of HBV-associated MN patients were involved in biological processes such as viral gene expression, and protein targeting to endoplasmic reticulum. We further verified that the overexpressed genes in ECs from HBV-associated MN were mainly enriched in regulation of protein targeting to endoplasmic reticulum, exocytosis, viral gene expression, IL-6 and IL-1 secretion when compared with anti-phospholipase A2 receptor (PLA2R)-positive idiopathic membranous nephropathy (IMN). The receptor-ligand crosstalk analysis revealed potential interactions between endothelial cells and other cells in HBV-associated-MN. These results offer new insight into the pathogenesis of HBV-associated MN and may identify new therapeutic targets for HBV-associated MN.

Investigating immunoregulatory effects of myeloid cell autophagy in acute and chronic inflammation.

Studies have highlighted a critical role for autophagy in the regulation of multiple cytokines. Autophagy inhibits the release of interleukin (IL)-1 family cytokines, including IL-1α, IL-1ß and IL-18, by myeloid cells. This, in turn, impacts the release of other cytokines by myeloid cells, as well as other cells of the immune system, including IL-22, IL-23, IL-17 and interferon-γ. Here, we assessed the impact of genetic depletion of the autophagy gene Atg7 in myeloid cells on acute and chronic inflammation. In a model of acute lipopolysaccharide-induced endotoxemia, loss of autophagy in myeloid cells resulted in increased release of proinflammatory cytokines, both locally and systemically. By contrast, loss of Atg7 in myeloid cells in the Lyn-/- model of lupus-like autoimmunity resulted in reduced systemic release of IL-6 and IL-10, with no effects on other cytokines observed. In addition, Lyn-/- mice with autophagy-deficient myeloid cells showed reduced expression of autoantibodies relevant to systemic lupus erythematosus, including anti-histone and anti-Smith protein. In vitro, loss of autophagy, through pharmacological inhibition or small interfering RNA against Becn1, inhibited IL-10 release by human and mouse myeloid cells. This effect was evident at the level of Il10 messenger RNA expression. Our data highlight potentially important differences in the role of myeloid cell autophagy in acute and chronic inflammation and demonstrate a direct role for autophagy in the production and release of IL-10 by macrophages.

High levels of platelet-to-lymphocyte ratio may predict reduced risk of end stage of renal disease in Chinese patients with MPO-ANCA associated vasculitis. / 血小板/淋巴细胞比率比值升高可能预示中国MPO-ANCAç›¸å ³æ€§è¡€ç®¡ç‚Žæ‚£è€ è¿›å±•è‡³ç»ˆæœ«æœŸè‚¾ç— çš„é£Žé™©è¾ƒä½Ž.

OBJECTIVES: Platelet-to-lymphocyte ratio (PLR) has recently been investigated as a new inflammatory marker in many inflammatory diseases, including systemic lupus erythematosus and immunoglobulin A vasculitis. However, there were very few reports regarding the clinical role of PLR in patients with anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis. This study was thus undertaken to investigate the relationship between inflammatory response and disease activity in Chinese patients with myeloperoxidase-anti-neutrophil cytoplasmic antibody (MPO-ANCA) associated vasculitis. Furthermore, we evaluated whether PLR predicts the progression of end stage of renal disease (ESRD) and all-cause mortality. METHODS: The clinical, laboratory and pathological data, and the outcomes of MPO-ANCA associated vasculitis patients were collected. The Spearman correlation coefficient was computed to examine the association between 2 continuous variables. Cox regression analysis was used to estimate the association between PLR and ESRD or all-cause mortality. RESULTS: A total of 190 consecutive patients with MPO-ANCA associated vasculitis were included in this study. Baseline PLR was positively correlated with CRP (r=0.333, P<0.001) and ESR (r=0.218, P=0.003). PLR had no obvious correlation with Birmingham Vasculitis Activity Score (BVAS). Patients having PLR≥330 exhibited better cumulative renal survival rates than those having PLR<330 (P=0.017). However, there was no significant difference in the cumulative patient survival rates between patients with PLR≥330 and those with PLR<330 at diagnosis (P>0.05). In multivariate analysis, PLR is associated with the decreased risk of ESRD (P=0.038, HR=0.518, 95% CI 0.278 to 0.963). We did not find an association between PLR with all-cause mortality using multivariate analysis (HR=1.081, 95% CI 0.591 to 1.976, P=0.801). CONCLUSIONS: PLR is positively correlated with CRP and ESR. Furthermore, PLR may independently predict the risk of ESRD.

Improving cell viability using counterflow centrifugal elutriation.

BACKGROUND: Cell viability is an important release criterion in the manufacturing of cell therapy products. Low cell viability can have significant impact on product quality and manufacturing efficiency. Counterflow centrifugation technology has been applied to the manufacturing of cell therapy products, to enable cell separation based on size and density. This study evaluated the utility of counterflow centrifugation technology for dead cell removal to improve cell viability of the final product. METHODS: Jurkat cell cultures with low and high dead cell burden were subjected to counterflow centrifugal elutriation to determine the correlation between process parameters (e.g., flow rate, centrifugal force) and processing outcomes (i.e., cell recovery and viability). Subsequently, the optimized parameters were applied to dead cell elutriation using expanded T cells and freshly isolated human amniotic epithelial cells (hAECs). The efficiency of dead cell removal, cell function and post-thaw viability were compared. RESULTS: Elutriation using a low flow rate allowed better control of viable cell recovery from both low and high dead cell burden cultures of Jurkat cells. The viability of T cells and hAECs was improved by counterflow centrifugal processing, from 80.67% ± 2.33 to 94.73% ± 1.19 and 79.19% ± 5.35 to 90.34% ± 3.59, respectively. Processing increased the proliferation rate of T cells, while the metabolic activity of hAECs was unchanged. CONCLUSION: Counterflow centrifugal elutriation can be added as an integrated step to the automated wash-and-concentrate protocol for cell manufacturing to remove dead cells and improve cell viability of the final product.

Heterologous Immunity Between SARS-CoV-2 and Pathogenic Bacteria.

Heterologous immunity, when the memory T cell response elicited by one pathogen recognizes another pathogen, has been offered as a contributing factor for the high variability in coronavirus disease 2019 (COVID-19) severity outcomes. Here we demonstrate that sensitization with bacterial peptides can induce heterologous immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) derived peptides and that vaccination with the SARS-CoV-2 spike protein can induce heterologous immunity to bacterial peptides. Using in silico prediction methods, we identified 6 bacterial peptides with sequence homology to either the spike protein or non-structural protein 3 (NSP3) of SARS-CoV-2. Notwithstanding the effects of bystander activation, in vitro co-cultures showed that all individuals tested (n=18) developed heterologous immunity to SARS-CoV-2 peptides when sensitized with the identified bacterial peptides. T cell recall responses measured included cytokine production (IFN-γ, TNF, IL-2), activation (CD69) and proliferation (CellTrace). As an extension of the principle of heterologous immunity between bacterial pathogens and COVID-19, we tracked donor responses before and after SARS-CoV-2 vaccination and measured the cross-reactive T cell responses to bacterial peptides with similar sequence homology to the spike protein. We found that SARS-CoV-2 vaccination could induce heterologous immunity to bacterial peptides. These findings provide a mechanism for heterologous T cell immunity between common bacterial pathogens and SARS-CoV-2, which may explain the high variance in COVID-19 outcomes from asymptomatic to severe. We also demonstrate proof-of-concept that SARS-CoV-2 vaccination can induce heterologous immunity to pathogenic bacteria derived peptides.

Ageing enhances cellular immunity to myeloperoxidase and experimental anti-myeloperoxidase glomerulonephritis.

OBJECTIVES: ANCA-associated vasculitis (AAV) is an autoimmune disease characterized by small blood vessel inflammation, commonly affecting the kidneys and respiratory tract. It is unclear why the incidence of this condition increases with age. Previous studies in a passive antibody transfer system in aged mice have implicated innate effectors. To test the hypothesis that autoimmunity to myeloperoxidase (MPO), an autoantigen responsible for AAV, increases with age, anti-MPO autoimmunity was studied in murine models of active autoimmunity and disease induced by cellular immunity. METHODS: Young (8 weeks) and aged (either 15 or 22 months) mice were immunized with whole proteins or peptides from ovalbumin, as a model foreign antigen, or MPO protein or peptides. Mice were subjected to a model of active anti-MPO glomerulonephritis. Cellular and humoral immune responses, and tissue inflammation were assessed. RESULTS: While cellular immunity to ovalbumin was diminished in aged mice, cellular autoimmunity to MPO and its immunodominant CD4+ and CD8+ T cell epitopes was increased after immunization with either MPO peptides or whole MPO protein, assessed by peptide and antigen-specific production of the pro-inflammatory cytokines IFN-γ and IL-17A. MPO-ANCA titres were not increased in aged mice compared with young mice. In experimental anti-MPO glomerulonephritis, cell-mediated injury was increased, likely due to CD4+ and CD8+ T cells, innate immunity and the increased vulnerability of aged kidneys. CONCLUSION: Heightened cellular immunity to MPO develops with ageing in mice and may contribute to the increased incidence and severity of AAV in older people.

Clinical features and outcomes of anti-neutrophil cytoplasmic autoantibody-associated vasculitis in Chinese childhood-onset patients.

Data on anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) are limited in children. This study is to determine the clinical features and outcomes of childhood-onset AAV. A retrospective study was performed on patients who were diagnosed with AAV before 18 years old in Xiangya Hospital. Their medical records were analyzed by retrospective review. Sixteen patients were diagnosed with AAV before 18 years old in the past 9 years, with an average age of 13.3 ± 3.3 years and 13 of them were female. There were 15 patients with microscopic polyangiitis (MPA) and 1 with Wegener's granulomatosis. The interval between onset of disease and diagnosis of AAV was 2 (1.5-3) months. Most patients (15/16, 93.8%) had multi-organ involvement, and all patients had renal involvement with 7 (43.8%) patients requiring dialysis at presentation. Eleven patients underwent a renal biopsy, of which mixed class and sclerotic class were the most two common histological types. All patients received immunosuppressive therapy for induction therapy including intravenous administrations of methylprednisolone (MP) pulse therapy for 8 patients. 8 patients (50%) achieved remission after induction therapy. After a median follow-up of 46.3 ± 36.1 months, nine (56.3%) patients progressed to end-stage renal disease (ESRD) and 5 (31.3%) patients died. Childhood-onset AAV showed similar clinical and pathological features compared to those of adults, except that it usually occurs in girls. The most commonly involved organ was the kidney, and it had a high risk of progression to ESRD. Early diagnosis and initiation of appropriate immunomodulatory therapy would be important to improve outcomes.