Spatial proteomics landscape and immune signature analysis of renal sample of lupus nephritis based on laser-captured microsection.

OBJECTIVE: We aimed to reveal a spatial proteomic and immune signature of kidney function regions in lupus nephritis (LN). MATERIAL AND METHODS: The laser capture microdissection (LCM) was used to isolate the glomerulus, tubules, and interstitial of the kidney from paraffin samples. The data-independent acquisition (DIA) method was used to collect proteomics data. The bioinformatic analysis was performed. RESULTS: A total of 49,658 peptides and 4056 proteins were quantitated. Our results first showed that a high proportion of activated NK cells, naive B cells, and neutrophils in the glomerulus, activated NK cells in interstitial, and resting NK cells were accumulated in tubules in LN. The immune-related function analysis of differential expression proteins in different regions indicated that the glomerulus and interstitial were major sites of immune disturbance and regulation connected with immune response activation. Furthermore, we identified 7, 8, and 9 hub genes in LN's glomerulus, renal interstitial, and tubules. These hub genes were significantly correlated with the infiltration of immune cell subsets. We screened out ALB, CTSB, LCN2, A2M, CDC42, VIM, LTF, and CD14, which show higher performance as candidate biomarkers after correlation analysis with clinical indexes. The function within three regions of the kidney was analyzed. The differential expression proteins (DEGs) between interstitial and glomerulus were significantly enriched in the immune-related biological processes, and myeloid leukocyte-mediated immunity and cellular response to hormone stimulus. The DEGs between tubules and glomerulus were significantly enriched in cell activation and leukocyte-mediated immunity. While the DEGs between tubules and interstitial were enriched in response to lipid, antigen processing, and presentation of peptide antigen response to oxygen-containing compound, the results indicated a different function within kidney regions. CONCLUSIONS: Collectively, we revealed spatial proteomics and immune signature of LN kidney regions by combined using LCM and DIA.

GLS1-mediated glutaminolysis unbridled by MALT1 protease promotes psoriasis pathogenesis.

Psoriasis is a severe disease associated with the disturbance of metabolism and inflammation, but the molecular mechanisms underlying these aspects of psoriasis pathology are poorly understood. Here, we report that glutaminase 1-mediated (GLS1-mediated) glutaminolysis was aberrantly activated in patients with psoriasis and in psoriasis-like mouse models, which promoted Th17 and γδ T17 (IL-17A-producing γδ T) cell differentiation through enhancement of histone H3 acetylation of the Il17a promoter, thereby contributing to the immune imbalance and development of psoriasis. We further demonstrate that mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) protease was constitutively active in psoriatic CD4+ and γδ T cells, thereby supporting GLS1 expression by stabilizing c-Jun, which directly binds to the GLS1 promoter region. Blocking the activity of either GLS1 or MALT1 protease resolved Th17 and γδ T17 cell differentiation and epidermal hyperplasia in the psoriasis-like mouse models. Finally, IL-17A enhanced GLS1 expression via the MALT1/cJun pathway in keratinocytes, resulting in hyperproliferation of and chemokine production by keratinocytes. Our findings identify the role of the MALT1/cJun/GLS1/glutaminolysis/H3 acetylation/T17 axis in psoriasis pathogenesis and reveal potential therapeutic targets for this disease.

Protease Inhibitor Use in COVID-19.

The outbreak of a large plaque, novel coronavirus pneumonia (NCP), which also named Coronavirus Disease 2019 (COVID-19) by the WHO, has detrimentally affected the livelihood and health of people in China. During the spread of COVID-19, colleagues who have been working at the frontline have had to face many new challenges in the treatment and prevention of NCP. Therefore, we have provided suggestions for the diagnosis, treatment, and prevention of the novel coronavirus pneumonia in the current epidemic situation based on the latest reports and the experience of doctors treating COVID-19 in our hospital. We recommend lopinavir/ritonavir as the effective drugs for antiviral treatment according to our experience in administering lopinavir/ritonavir to COVID-19 patients and the successful cases of these drugs in treating MERS and SARS, but need more clinical data to prove their efficacy in treating COVID-19.

Interferon Kappa Is Important for Keratinocyte Host Defense against Herpes Simplex Virus-1.

Type I interferon kappa (IFNκ) is selectively expressed in human keratinocytes. Herpes simplex virus-1 (HSV-1) is a human pathogen that infects keratinocytes and causes lytic skin lesions. Whether IFNκ plays a role in keratinocyte host defense against HSV-1 has not been investigated. In this study, we found that IFNκ mRNA expression was induced by addition of recombinant IFNκ and poly (I:C); and its expression level was significantly greater than IFNa2, IFNb1, and IFNL1 in both undifferentiated and differentiated normal human epidermal keratinocytes (NHEKs) under resting and stimulation conditions. Although IFNe was expressed at a relatively higher level than other IFNs in resting undifferentiated NHEK, its expression level did not change after stimulation with recombinant IFNκ and poly (I:C). HSV-1 infection inhibited gene expression of IFNκ and IFNe in NHEK. Silencing IFNκ in NHEK led to significantly enhanced HSV-1 replication in both undifferentiated and differentiated NHEK compared to scrambled siRNA-transfected cells, while the addition of recombinant IFNκ significantly reduced HSV-1 replication in NHEK. In addition, we found that IFNκ did not regulate protein expression of NHEK differentiation markers. Our results demonstrate that IFNκ is the dominant type of IFNs in keratinocytes and it has an important function for keratinocytes to combat HSV-1 infection.

Interferon Kappa Is Up-Regulated in Psoriasis and It Up-Regulates Psoriasis-Associated Cytokines in vivo.

PURPOSE: There is increased type I interferon signature in psoriasis patients. Interferon-kappa (IFN-κ) is a member of type I interferon family that is constitutively expressed by keratinocytes. In this study, we investigate whether IFN-κ is involved in psoriasis etiology. PATIENTS AND METHODS: Twenty healthy individuals, 20 psoriasis vulgaris patients and 10 atopic dermatitis (AD) were included for this study. Immunohistochemistry staining, normal human epidermal keratinocytes (NHEK) culture, Ca2Cl-induced differentiation, quantitative reverse transcription (qRT-PCR), ELISA and murine experiments were performed. RESULTS: We found IFN-κ protein expression was extremely low in the epidermis of normal skin, but it was significantly increased in the suprabasal layers of epidermal keratinocytes in psoriatic skin lesions. However, its expression in the skin lesions of AD was similar to normal skin. Additionally, IFN-κ protein was detected in sera from psoriasis patients, but not in sera from normal subjects and AD. We further investigated the regulation of IFNk gene expression in NHEK. We found that IFNk was significantly induced by types of nucleic acid pathogen recognition receptor (PRR) agonists in NHEK. While its expression was significantly induced by itself and IFN-γ, it was inhibited by type 2 immunity cytokines IL4 and IL13; other inflammatory cytokines including IL1 super-family members and IL17A did not alter its expression. Addition of recombinant IFN-κ did not affect keratinocytes differentiation. Using the murine experimental model, we demonstrated that subcutaneous administration of recombinant IFN-κ did not increase skin thickness, but significantly increased the transcription of TNFA and IL17A in mice skin. CONCLUSION: Increased IFN-κ in psoriasis may be caused by injured cells-released nucleic acids, increased IFN-γ and self-activation. Its enhancement may contribute to the etiology of the disease by enhancing TNFA and IL17A gene expression.

Antiapoptotic properties of MALT1 protease are associated with redox homeostasis in ABC-DLBCL cells.

Mucosa-associated lymphoid tissue lymphoma translocation protein-1 (MALT1) protease presents crucial antiapoptotic properties in activated B cell-like diffuse large B-cell lymphoma (ABC-DLBCL); however, the mechanism is unclear. Here, we reported that inhibition of MALT1 protease in ABC-DLBCL cells led to cell apoptosis, along with elevated mitochondrial reactive oxygen species production and a reduced oxygen consumption rate. These alterations induced by MALT1 protease inhibition were associated with reduced expression of glutaminase (GLS1) and glutathione levels. We further show that MALT1 protease was required for the activation and nuclear translocation of c-Jun, which functions as a transcription factor of the GLS1 gene by binding directly to its promoter region. Taken together, MALT1 protease maintained mitochondrial redox homeostasis and mitochondrial bioenergetics through the MALT1-c-Jun-GLS1-coupled metabolic pathway to defend against apoptosis in ABC-DLBCL cells, which raises exciting possibilities regarding targeting of the MALT1-c-Jun-GLS1 axis as a potential therapeutic strategy against ABC-DLBCL.

Feruloylated Oligosaccharides Alleviate Dextran Sulfate Sodium-Induced Colitis in Vivo.

The imbalance of T lymphocyte subsets substantially conduces to disturbed intestinal immune system and succeeding colonic tissue damage in inflammatory bowel diseases. It is considered that regulation of phytochemicals on cytokine production potentially provides a broad prospect for the exploitation of immunomodulatory agents. Here, we reported that oral administration of feruloylated oligosaccharides (FOs) effectively alleviated mice colitis disease induced by dextran sulfate sodium (DSS). FOs decreased the percentage of T helper (Th)17 cells and downregulated the production of Th17-specific cytokines. In contrast, FOs increased the percentage of regulatory T (Treg) cells and elevated the production of Treg-specific cytokines in colons of DSS-challenged mice. These results indicated that FOs restored the immunologic equilibrium of Th17 and Treg subsets, hereby ameliorating the deterioration of colitis. Furthermore, FOs diminished the secretion of interleukin (IL)-23 and IL-6 but enhanced the transforming growth factor-ß1 (TGF-ß1) in dendritic cells in vitro and in vivo, which contributed to the restoration of Th17 and Treg cells immune balance. The mechanistic analysis showed that the regulation of FOs on IL-23 and IL-6 was associated with the nuclear factor-κ-gene binding signaling pathway and TGF-ß1 with mitogen-activated protein kinase-activator protein 1 signaling pathway. Taken together, oral administration of FOs exerted potent immunomodulatory effects against mice colitis via restoring the immune balance of Th17 and Treg cells.