HOIL-1 ubiquitin ligase activity targets unbranched glucosaccharides and is required to prevent polyglucosan accumulation.

HOIL-1, a component of the linear ubiquitin chain assembly complex (LUBAC), ubiquitylates serine and threonine residues in proteins by esterification. Here, we report that mice expressing an E3 ligase-inactive HOIL-1[C458S] mutant accumulate polyglucosan in brain, heart and other organs, indicating that HOIL-1's E3 ligase activity is essential to prevent these toxic polysaccharide deposits from accumulating. We found that HOIL-1 monoubiquitylates glycogen and α1:4-linked maltoheptaose in vitro and identify the C6 hydroxyl moiety of glucose as the site of ester-linked ubiquitylation. The monoubiquitylation of maltoheptaose was accelerated > 100-fold by the interaction of Met1-linked or Lys63-linked ubiquitin oligomers with the RBR domain of HOIL-1. HOIL-1 also transferred pre-formed ubiquitin oligomers to maltoheptaose en bloc, producing polyubiquitylated maltoheptaose in one catalytic step. The Sharpin and HOIP components of LUBAC, but not HOIL-1, bound to unbranched and infrequently branched glucose polymers in vitro, but not to highly branched mammalian glycogen, suggesting a potential function in targeting HOIL-1 to unbranched glucosaccharides in cells. We suggest that monoubiquitylation of unbranched glucosaccharides may initiate their removal from cells, preventing precipitation as polyglucosan.

Molecular control of the NEMO family of ubiquitin-binding proteins.

Research over the past decade has revealed how NF-κB essential modulator (NEMO; also known as IKKγ) regulates the IKKα-IKKß signalling axis in the innate immune system. The discovery that NEMO is a polyubiquitin-binding protein and that the IKK complex is modulated by other protein kinases that are themselves controlled by polyubiquitin chains has provided a deeper molecular understanding of the non-degradative roles of ubiquitylation. New mechanistic insights of NEMO and related polyubiquitin-binding proteins have become a paradigm for how the interplay between phosphorylation and ubiquitylation controls cell signalling networks in health and disease.

IKKß is required for the formation of the NLRP3 inflammasome.

The rapid formation and activation of the NLRP3 inflammasome is induced by co-stimulation with LPS and nigericin. It requires the LPS-stimulated activation of IKKß, which exerts its effects independently of de novo gene transcription, protein translation and other protein kinases activated by IKKß. IKKß is not required for the nigericin-induced dispersion of the trans-Golgi network (TGN), but to bring NLRP3 in proximity with TGN38. The nigericin-induced dispersion of the Golgi is enhanced by co-stimulation with LPS, and this enhancement is IKKß-dependent. Prolonged stimulation with LPS to increase the expression of NLRP3, followed by stimulation with nigericin, produced larger TGN38-positive puncta, and the ensuing activation of the NLRP3 inflammasome was also suppressed by IKKß inhibitors added prior to stimulation with nigericin. IKKß therefore has a key role in recruiting NLRP3 to the dispersed TGN, leading to the formation and activation of the NLRP3 inflammasome.

ABIN2 Function Is Required To Suppress DSS-Induced Colitis by a Tpl2-Independent Mechanism.

The A20-binding inhibitor of NF-κB 2 (ABIN2) interacts with Met1-linked ubiquitin chains and is an integral component of the tumor progression locus 2 (Tpl2) kinase complex. We generated a knock-in mouse expressing the ubiquitin-binding-defective mutant ABIN2[D310N]. The expression of Tpl2 and its activation by TLR agonists in macrophages or by IL-1ß in fibroblasts from these mice was unimpaired, indicating that the interaction of ABIN2 with ubiquitin oligomers is not required for the stability or activation of Tpl2. The ABIN2[D310N] mice displayed intestinal inflammation and hypersensitivity to dextran sodium sulfate-induced colitis, an effect that was mediated by radiation-resistant cells rather than by hematopioetic cells. The IL-1ß-dependent induction of cyclooxygenase 2 (COX2) and the secretion of PGE2 was reduced in mouse embryonic fibroblasts and intestinal myofibroblasts (IMFs) from ABIN2[D310N] mice. These observations are similar to those reported for the Tpl2 knockout (KO) mice (Roulis et al. 2014. Proc. Natl. Acad. Sci. USA 111: E4658-E4667), but the IL-1ß-dependent production of COX2 and PGE2 in mouse embryonic fibroblasts or IMFs was unaffected by pharmacological inhibition of Tpl2 in wild-type mice. The expression of ABIN2 is decreased drastically in Tpl2 KO mice. These and other lines of evidence suggest that the hypersensitivity of Tpl2 KO mice to dextran sodium sulfate-induced colitis is not caused by the loss of Tpl2 catalytic activity but by the loss of ABIN2, which impairs COX2 and PGE2 production in IMFs by a Tpl2 kinase-independent pathway.

Prospective evaluation of definitive chemoradiotherapy with volumetric modulated arc therapy in patients with muscle invasive carcinoma of urinary bladder.

INTRODUCTION: Concurrent chemoradiotherapy (CTRT) remains one of the treatment options in patients with muscle invasive bladder cancer (MIBC) unwilling/unsuitable for radical surgery. We evaluated the role of volumetric modulated arc therapy (VMAT) in MIBC patients treated with definitive CTRT. MATERIAL AND METHODS: 25 patients of histologically proven transitional cell MIBC (T2-T4a, N0, M0) unwilling/unsuitable for radical surgery (after maximal transurethral resection of bladder tumour) were recruited in this prospective study. Primary clinical target volume (CTV) consisted of the gross tumour and whole bladder. Primary planning target volume (PTV) and nodal PTV were prescribed 60 Gy and 54 Gy (both in 30 fractions). Concurrent chemotherapy was cisplatin (40 mg/m2) weekly. Acute toxicities were assessed as per Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Survival estimates were done from the date of registration using the Kaplan-Meier method. RESULTS: Median age was 70 years (37-80 years). Median overall treatment time was 45 days (44-51). Median number of chemotherapy cycles was 5 (range 3-6). 5 (20%) and 4 (16%) patients respectively suffered from acute grade ≥ 2 gastrointestinal and grade ≥ 2 genitourinary toxicities during treatment. One patient each had grade 3 anaemia and neutropenia. At a median follow-up of 34 months (10-45 months), 3-year progression-free survival and overall survival were 65.6% and 81.2% respectively. 3-year distant metastasis-free survival was 90.5%. Bladder preservation rate at 3 years was 68%. CONCLUSIONS: Definitive CTRT with VMAT is well tolerated in patients with MIBC unsuitable for surgery and yields decent survival and bladder preservation outcome.

Genetic variations in A20 DUB domain provide a genetic link to citrullination and neutrophil extracellular traps in systemic lupus erythematosus.

OBJECTIVES: Genetic variations in TNFAIP3 (A20) de-ubiquitinase (DUB) domain increase the risk of systemic lupus erythematosus (SLE) and rheumatoid arthritis. A20 is a negative regulator of NF-κB but the role of its DUB domain and related genetic variants remain unclear. We aimed to study the functional effects of A20 DUB-domain alterations in immune cells and understand its link to SLE pathogenesis. METHODS: CRISPR/Cas9 was used to generate human U937 monocytes with A20 DUB-inactivating C103A knock-in (KI) mutation. Whole genome RNA-sequencing was used to identify differentially expressed genes between WT and C103A KI cells. Functional studies were performed in A20 C103A U937 cells and in immune cells from A20 C103A mice and genotyped healthy individuals with A20 DUB polymorphism rs2230926. Neutrophil extracellular trap (NET) formation was addressed ex vivo in neutrophils from A20 C103A mice and SLE-patients with rs2230926. RESULTS: Genetic disruption of A20 DUB domain in human and murine myeloid cells did not give rise to enhanced NF-κB signalling. Instead, cells with C103A mutation or rs2230926 polymorphism presented an upregulated expression of PADI4, an enzyme regulating protein citrullination and NET formation, two key mechanisms in autoimmune pathology. A20 C103A cells exhibited enhanced protein citrullination and extracellular trap formation, which could be suppressed by selective PAD4 inhibition. Moreover, SLE-patients with rs2230926 showed increased NETs and increased frequency of autoantibodies to citrullinated epitopes. CONCLUSIONS: We propose that genetic alterations disrupting the A20 DUB domain mediate increased susceptibility to SLE through the upregulation of PADI4 with resultant protein citrullination and extracellular trap formation.

Suppression of IRAK1 or IRAK4 Catalytic Activity, but Not Type 1 IFN Signaling, Prevents Lupus Nephritis in Mice Expressing a Ubiquitin Binding-Defective Mutant of ABIN1.

Polymorphisms in the TNIP1 gene encoding A20-binding inhibitor of NF-κB1 (ABIN1) predispose to lupus and other autoimmune diseases in at least eight human populations. We found previously that knock-in mice expressing a ubiquitin-binding-defective mutant of ABIN1 (ABIN1[D485N]) develop autoimmunity as they age and succumb to a disease resembling lupus nephritis in humans. In this article, we report that Flt3-derived dendritic cells from these mice overproduced type 1 IFNs upon stimulation with ligands that activate TLR7 or TLR9. However, crossing ABIN1[D485N] mice to IFNAR1-knockout mice that do not express the α-subunit of the type 1 IFNR did not prevent splenomegaly, the appearance of high serum levels of autoantibodies and other Igs, or liver inflammation and only reduced kidney inflammation modestly. In contrast, crossing ABIN1[D485N] mice to knock-in mice expressing catalytically inactive mutants of IRAK1 or IRAK4 prevented splenomegaly, autoimmunity, and liver and kidney inflammation. Our results support the notion that IRAK1 and/or IRAK4 are attractive targets for the development of drugs to prevent, and perhaps treat, lupus nephritis and other autoinflammatory diseases caused by the decreased ability of ABIN1 or other proteins to restrict the strength of MyD88 signaling.

Laparoscopic-Assisted Uterus Retrieval From Live Organ Donors for Uterine Transplant.

STUDY OBJECTIVE: The authors present the first ever laparoscopic-assisted uterus retrieval in a live donor for uterus transplant. DESIGN: A step-by-step surgical demonstration. SETTING: Galaxy CARE Laparoscopy Institute, Pune, India. PATIENTS: Two patients, ages 21 and 26 years, with Mayer-Rokitansky-Küster-Hauser syndrome and Asherman syndrome, respectively, with their mothers as donors. INTERVENTIONS: A 12-member team was formed. After a review of the available literature on uterine transplant, a protocol was formulated and submitted to the Institutional Review Board (IRB). Approval from the Institutional Review Board was obtained. Thorough screening of the candidates was done. Two consecutive uterine transplants were done on 2 successive days. Vessels were harvested laparoscopically in both donors. Uterus was retrieved through a small abdominal incision, to prevent any injury to the uterus and harvested vessels. Uterus was transplanted in the recipients by end-to-side anastomosis of the harvested vessels to the external iliac vessels, followed by anchoring of supports of the donor uterus to those of the recipients. MEASUREMENTS AND MAIN RESULTS: Surgical intra- and postoperative parameters, postoperative investigations, and follow-up data of 4 months. The operative time for laparoscopic donor surgery was 4 hours. Bench surgery took 45 minutes. The recipient surgery was completed in 4 hours. There were no intraoperative or immediate postoperative complications. Both recipients started menstruating after 34 days and 48 days, respectively, and have had 3 cycles of menses at regular intervals to date. After discharge, follow-up cervical biopsies at 3 weekly intervals showed no signs of rejection. Uterine artery Doppler ultrasound showed good flow in both patients. CONCLUSION: Laparoscopic-assisted donor retrieval is feasible and affords all advantages of a minimally invasive technique. It helps in better dissection of vessels, shortens the operative time, and helps minimize tissue handling, thereby reducing the morbidity of the procedure.

Role of benzydamine hydrochloride in the prevention of oral mucositis in head and neck cancer patients treated with radiotherapy (>50 Gy) with or without chemotherapy.

PURPOSE: Benzydamine is recommended for prophylaxis of oral mucositis (OM) in head and neck cancer (HNC) patients for radiation doses (<50 Gy). This study evaluates role of benzydamine for higher radiation doses (>50 Gy) with or without chemotherapy. METHODS: One hundred twenty patients of HNC with planned radiation doses of ≥60 Gy were randomized to group A (control radiotherapy alone), group B (study radiotherapy alone), group C (control chemoradiotherapy), or to group D (study chemoradiotherapy). Groups A and C were advised saline mouth rinses, and in groups B and D, additional benzydamine rinses (0.15%) were advised. Mucositis grading was done with both WHO (WHO-M) and CTCAE (CTC-M) version 4.0 (common terminology criteria for adverse events) weekly. RESULTS: Patient characteristics are presented in the table. Patients in group B had lesser grade 3 WHO-M and CTC-M as compared to group A, 62.1 vs. 36.4% (p = 0.038) and 51.7 vs. 27.3% (p = 0.043), respectively. The rates of Ryle's tube feeding (RTF), intravenous fluid supplementation (IVF), and hospitalization were also lesser in group B as compared to A, 34.5 vs. 21.2% (p = 0.18), 27.6 vs. 9.1% (p = 0.06), and 6.9 vs. 0% (p = 0.21), respectively. WHO-M and CTC-M in groups C and D were not statistically different, 64.3 vs. 43.3% (p = 0.091) and 53.6% vs. 43.3% (p = 0.30), respectively. The rates of RTF, IVF, and hospitalization were all lesser but p > 0.05. CONCLUSION: Benzydamine significantly reduces OM even at doses >50 Gy in HNC patients. Its role in patients receiving concurrent chemotherapy further needs to be evaluated.

IRAK-1 bypasses priming and directly links TLRs to rapid NLRP3 inflammasome activation.

Pathogenic infections and tissue injuries trigger the assembly of inflammasomes, cytosolic protein complexes that activate caspase-1, leading to cleavage of pro-IL-1ß and pro-IL-18 and to pyroptosis, a proinflammatory cell death program. Although microbial recognition by Toll-like receptors (TLRs) is known to induce the synthesis of the major caspase-1 substrate pro-IL-1ß, the role of TLRs has been considered limited to up-regulation of the inflammasome components. During infection with a virulent microbe, TLRs and nucleotide-binding oligomerization domain-like receptors (NLRs) are likely activated simultaneously. To examine the requirements and outcomes of combined activation, we stimulated TLRs and a specific NLR, nucleotide binding and oligomerization, leucine-rich repeat, pyrin domain-containing 3 (NLRP3), simultaneously and discovered that such activation triggers rapid caspase-1 cleavage, leading to secretion of presynthesized inflammatory molecules and pyroptosis. This acute caspase-1 activation is independent of new protein synthesis and depends on the TLR-signaling molecule IL-1 receptor-associated kinase (IRAK-1) and its kinase activity. Importantly, Listeria monocytogenes induces NLRP3-dependent rapid caspase-1 activation and pyroptosis, both of which are compromised in IRAK-1-deficient macrophages. Our results reveal that simultaneous sensing of microbial ligands and virulence factors by TLRs and NLRP3, respectively, leads to a rapid TLR- and IRAK-1-dependent assembly of the NLRP3 inflammasome complex, and that such activation is important for release of alarmins, pyroptosis, and early IFN-γ production by memory CD8 T cells, all of which could be critical for early host defense.

Suppression of interferon ß gene transcription by inhibitors of bromodomain and extra-terminal (BET) family members.

PLK (Polo-like kinase) inhibitors, such as BI-2536, have been reported to suppress IFNB (encoding IFNß, interferon ß) gene transcription induced by ligands that activate TLR3 (Toll-like receptor 3) and TLR4. In the present study, we found that BI-2536 is likely to exert this effect by preventing the interaction of the transcription factors IRF3 (interferon-regulatory factor 3) and c-Jun with the IFNB promoter, but without affecting the TBK1 {TANK [TRAF (tumour-necrosis-factor-receptor-associated factor)-associated nuclear factor κB activator]-binding kinase 1}-catalysed phosphorylation of IRF3 at Ser³96, the dimerization and nuclear translocation of IRF3 or the phosphorylation of c-Jun and ATF2 (activating transcription factor 2). Although BI-2536 inhibits few other kinases tested, it interacts with BET (bromodomain and extra-terminal) family members and displaces them from acetylated lysine residues on histones. We found that BET inhibitors that do not inhibit PLKs phenocopied the effect of BI-2536 on IFNB gene transcription. Similarly, BET inhibitors blocked the interaction of IRF5 with the IFNB promoter and the secretion of IFNß induced by TLR7 or TLR9 ligands in the human plasmacytoid dendritic cell line GEN2.2, but without affecting the nuclear translocation of IRF5. We found that the BET family member BRD4 (bromodomain-containing protein 4) was associated with the IFNB promoter and that this interaction was enhanced by TLR3- or TLR4-ligation and prevented by BI-2536 and other BET inhibitors. Our results establish that BET family members are essential for TLR-stimulated IFNB gene transcription by permitting transcription factors to interact with the IFNB promoter. They also show that the interaction of the IFNB promoter with BRD4 is regulated by TLR ligation and that BI-2536 is likely to suppress IFNB gene transcription by targeting BET family members.

Two phases of inflammatory mediator production defined by the study of IRAK2 and IRAK1 knock-in mice.

The roles of IL-1R-associated kinase (IRAK)2 and IRAK1 in cytokine production were investigated using immune cells from knock-in mice expressing the TNFR-associated factor 6 (TRAF6) binding-defective mutant IRAK2[E525A] or the catalytically inactive IRAK1[D359A] mutant. In bone marrow-derived macrophages (BMDMs), the IRAK2-TRAF6 interaction was required for the late (2-8 h) but not the early phase (0-2 h) of il6 and tnfa mRNA production, and hence for IL-6 and TNF-α secretion by TLR agonists that signal via MyD88. Loss of the IRAK2-TRAF6 interaction had little effect on the MyD88-dependent production of anti-inflammatory molecules produced during the early phase, such as Dual Specificity Phosphatase 1, and a modest effect on IL-10 secretion. The LPS/TLR4-stimulated production of il6 and tnfa mRNA and IL-6 and TNF-α secretion was hardly affected, because the Toll/IL-1R domain-containing adapter-inducing IFN-ß (TRIF) signaling pathway was used instead of the IRAK2-TRAF6 interaction to sustain late-phase mRNA production. IRAK1 catalytic activity was not rate limiting for il6, tnfa, or il10 mRNA production or the secretion of these cytokines by BMDMs, but IFN-ß mRNA induction by TLR7 and TLR9 agonists was greatly delayed in plasmacytoid dendritic cells (pDCs) from IRAK1[D359A] mice. In contrast, IFN-ß mRNA production was little affected in pDCs from IRAK2[E525A] mice, but subsequent IFN-α mRNA production and IFN-α secretion were reduced. IFN-ß and IFN-α production were abolished in pDCs from IRAK1[D359A] × IRAK2[E525A] double knock-in mice. Our results establish that the IRAK2-TRAF6 interaction is rate limiting for the late, but not the early phase of cytokine production in BMDM and pDCs, and that the IRAK2-TRAF6 interaction is needed to sustain IκB-inducing kinase ß activity during prolonged activation of the MyD88 signaling network. [corrected]

DEAF1 is a Pellino1-interacting protein required for interferon production by Sendai virus and double-stranded RNA.

Double-stranded (ds) RNA of viral origin, a ligand for Melanoma Differentiation-associated gene 5 (MDA5) and Toll-Like Receptor 3 (TLR3), induces the TANK-Binding Kinase 1 (TBK1)-dependent phosphorylation and activation of Interferon Regulatory Factor 3 (IRF3) and the E3 ubiquitin ligase Pellino1, which are required for interferon ß (IFNß) gene transcription. Here, we report that Pellino1 interacts with the transcription factor Deformed Epidermal Autoregulatory Factor 1 (DEAF1). The interaction is independent of the E3 ligase activity of Pellino1, but weakened by the phosphorylation of Pellino1. We show that DEAF1 binds to the IFNß promoter and to IRF3 and IRF7, that it is required for the transcription of the IFNß gene and IFNß secretion in MEFs infected with Sendai virus or transfected with poly(I:C). DEAF1 is also needed for TLR3-dependent IFNß production. Taken together, our results identify DEAF1 as a novel component of the signal transduction network by which dsRNA of viral origin stimulates IFNß production.

Different functions of the common P/V/W and V-specific domains of rinderpest virus V protein in blocking IFN signalling.

The V proteins of paramyxoviruses are composed of two evolutionarily distinct domains, the N-terminal 75 % being common to the viral P, V and W proteins, and not highly conserved between viruses, whilst the remaining 25 % consists of a cysteine-rich V-specific domain, which is conserved across almost all paramyxoviruses. There is evidence supporting a number of different functions of the V proteins of morbilliviruses in blocking the signalling pathways of type I and II IFNs, but it is not clear which domains of V are responsible for which activities and whether all these activities are required for effective blockade of IFN signalling. We have shown here that the two domains of rinderpest virus V protein have distinct functions: the N-terminal domain acted to bind STAT1, whilst the C-terminal V-specific domain interacted with the IFN receptor-associated kinases Jak1 and Tyk2. Effective blockade of IFN signalling required the intact V protein.

ABIN1 dysfunction as a genetic basis for lupus nephritis.

The genetic factors underlying the pathogenesis of lupus nephritis associated with systemic lupus erythematosus are largely unknown, although animal studies indicate that nuclear factor (NF)-κB is involved. We reported previously that a knockin mouse expressing an inactive form of ABIN1 (ABIN1[D485N]) develops lupus-like autoimmune disease and demonstrates enhanced activation of NF-κB and mitogen-activated protein kinases in immune cells after toll-like receptor stimulation. In the current study, we show that ABIN1[D485N] mice develop progressive GN similar to class III and IV lupus nephritis in humans. To investigate the clinical relevance of ABIN1 dysfunction, we genotyped five single-nucleotide polymorphisms in the gene encoding ABIN1, TNIP1, in samples from European-American, African American, Asian, Gullah, and Hispanic participants in the Large Lupus Association Study 2. Comparing cases of systemic lupus erythematosus with nephritis and cases of systemic lupus erythematosus without nephritis revealed strong associations with lupus nephritis at rs7708392 in European Americans and rs4958881 in African Americans. Comparing cases of systemic lupus erythematosus with nephritis and healthy controls revealed a stronger association at rs7708392 in European Americans but not at rs4958881 in African Americans. Our data suggest that variants in the TNIP1 gene are associated with the risk for lupus nephritis and could be mechanistically involved in disease development via aberrant regulation of NF-κB and mitogen-activated protein kinase activity.

Effects of Viral Infections Like COVID-19 on Head and Neck Cancers: The Role of Neutrophil-Lymphocyte Counts and Ratios.

BACKGROUND: Over the last three years, the coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has had a global impact. COVID-19 has led to diagnostic and treatment delays in head and neck squamous cell cancers (HNSCCs). Both cancer and COVID-19 trigger systemic inflammatory responses that can result in cytokine storms, creating a favorable tumor microenvironment that supports tumor growth. Various studies have shown a positive association between increasing neutrophil-to-lymphocyte ratio (NLR) and disease severity in COVID-19. Studies have also shown that high NLR is associated with poor survival outcomes in cancer patients. Our aim is to investigate whether an increased NLR is linked to rapid tumor progression in patients with HNSCC who have also been affected by infections like COVID-19 in the pre-operative period. METHODS: This was a retrospective analysis of patients of HNSCC who were scheduled for surgery and had contracted COVID-19 in their pre-operative period between April 2021 and May 2021. The study analyzed pre- and post-COVID NLR in relation to disease progression in HNSCC. Statistical analysis was presented as an interquartile range and numbered with the percentage. Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 26.0, Armonk, NY) was utilized for the analysis. RESULTS: We evaluated 200 operable cases of which 38/200 (20%) patients with HNSCC were COVID-19 positive. Out of those COVID-19-positive patients, 27/38 (71%) patients got operated. Around, 11/38 (28.9%) patients were inoperable. And, 14/27 (53.8%) operated patients also had a change in treatment plan. The mean duration from the joint clinic treatment plan to the date of surgery was 25.18 days. Patients who had contracted COVID-19 and had a change in their treatment plan due to disease progression exhibited mean NLR values of 3.84 (pre-COVID) and 11.11 (post-COVID), with respective medians of 3.04 and 10.50. These differences showed a statistically significant p-value of 0.000. In contrast, patients who had no change in treatment plan displayed mean NLR values of 4.51 (pre-COVID) and 9.70 (post-COVID), with respective medians of 3.47 and 3.42, resulting in with a non-significant p-value of 0.082. CONCLUSION: This is a one-of-its-kind study that has evaluated the role of elevated NLR in patients with a COVID-19 virus infection and its relationship with the clinical progression of the disease. The findings suggest that elevated NLR in patients with HNSCC, along with concurrent SARS-CoV2 infection, may contribute to accelerated disease progression with an increase in tumor burden and nodal metastasis.

Pacritinib abrogates the lupus phenotype in ABIN1[D485N] mice.

OBJECTIVE: The aim of the study was to investigate whether the IRAK1/JAK2/Flt3 inhibitor pacritinib prevents disease development in the lupus-prone ABIN1[D485N] knock-in mouse. METHODS: ABIN1[D485N] knock-in mice aged 8 weeks were fed for 10 weeks on a diet containing pacritinib. Body weight was monitored, and serum collected at the end to measure pacritinib, autoantibody and immunoglobulin levels. Splenic immune cell populations were analysed, and the kidney, liver and lungs examined for pathology. RESULTS: Pacritinib prevented multiple facets of the lupus phenotype in ABIN1[D485N] knock-in mice, including splenomegaly, expansion of splenic germinal centre B cells, follicular T helper cells, and neutrophils, elevated serum levels of double-stranded DNA antibodies and immunoglobulins, glomerular IgA and lung inflammation. CONCLUSIONS: Pacritinib may be useful for the treatment of multiorgan inflammation in patients with lupus.

Posttranslational Regulation of Inflammasomes, Its Potential as Biomarkers and in the Identification of Novel Drugs Targets.

In this review, we have summarized classical post-translational modifications (PTMs) such as phosphorylation, ubiquitylation, and SUMOylation of the different components of one of the most studied NLRP3, and other emerging inflammasomes. We will highlight how the discovery of these modifications have provided mechanistic insight into the biology, function, and regulation of these multiprotein complexes not only in the context of the innate immune system but also in adaptive immunity, hematopoiesis, bone marrow transplantation, as well and their role in human diseases. We have also collected available information concerning less-studied modifications such as acetylation, ADP-ribosylation, nitrosylation, prenylation, citrullination, and emphasized their relevance in the regulation of inflammasome complex formation. We have described disease-associated mutations affecting PTMs of inflammasome components. Finally, we have discussed how a deeper understanding of different PTMs can help the development of biomarkers and identification of novel drug targets to treat diseases caused by the malfunctioning of inflammasomes.

Extramedullary Solitary Plasmacytoma of Larynx: A Rare Entity and Therapeutic Challenge.

Solitary extramedullary plasmacytoma is a rare entity. The diagnosis is established by clinical evaluation, detailed radiological workup and histopathology with immunohistochemistry markers. There is no clear standard of care for a solitary laryngeal plasmacytoma. A case of solitary laryngeal plasmacytoma is being reported here with the rationale for the chosen treatment modality.

Why are the phenotypes of TRAF6 knock-in and TRAF6 knock-out mice so different?

The expression of TNF-Receptor Associated Factor 6 (TRAF6) is essential for many physiological processes. Here we studied the phenotype of TRAF6[L74H] knock-in mice which are devoid of TRAF6 E3 ligase activity in every cell of the body, but express normal levels of the TRAF6 protein. Remarkably, TRAF6[L74H] mice have none of the phenotypes seen in TRAF6 KO mice. Instead TRAF6[L74H] mice display an entirely different phenotype, exhibiting autoimmunity, and severe inflammation of the skin and modest inflammation of the liver and lungs. Similar to mice with a Treg-specific knockout of TRAF6, or mice devoid of TRAF6 in all T cells, the CD4+ and CD8+ T cells in the spleen and lymph nodes displayed an activated effector memory phenotype with CD44high/CD62Llow expression on the cell surface. In contrast, T cells from WT mice exhibited the CD44low/CD62Lhigh phenotype characteristic of naïve T cells. The onset of autoimmunity and autoinflammation in TRAF6[L74H] mice (two weeks) was much faster than in mice with a Treg-specific knockout of TRAF6 or lacking TRAF6 expression in all T cells (2-3 months) and we discuss whether this may be caused by secondary inflammation of other tissues. The distinct phenotypes of mice lacking TRAF6 expression in all cells appears to be explained by their inability to signal via TNF Receptor Superfamily members, which does not seem to be impaired significantly in TRAF6[L74H] mice.