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Objective To investigate the role of calcium/calmodulin-dependent protein kinase IV (CaMK4) in the development of joint injury in a mouse model of arthritis and patients with RA. Methods Camk4-deficient, Camk4flox/floxLck-Cre, and mice treated with CaMK4 inhibitor KN-93 or KN-93 encapsulated in nanoparticles tagged with CD4 or CD8 antibodies were subjected to collagen-induced arthritis (CIA). Inflammatory cytokine levels, humoral immune response, synovitis, and T-cell activation were recorded. CAMK4 gene expression was measured in CD4+ T cells from healthy participants and patients with active RA. Micro-CT and histology were used to assess joint pathology. CD4+ and CD14+ cells in patients with RA were subjected to Th17 or osteoclast differentiation, respectively. Results CaMK4-deficient mice subjected to CIA displayed improved clinical scores and decreased numbers of Th17 cells. KN-93 treatment significantly reduced joint destruction by decreasing the production of inflammatory cytokines. Furthermore, Camk4flox/floxLck-Cre mice and mice treated with KN93-loaded CD4 antibody-tagged nanoparticles developed fewer Th17 cells and less severe arthritis. CaMK4 inhibition mitigated IL-17 production by CD4+ cells in patients with RA. The number of in vitro differentiated osteoclasts from CD14+ cells in patients with RA was significantly decreased with CaMK4 inhibitors. Conclusion Using global and CD4-cell-targeted pharmacologic approaches and conditionally deficient mice, we demonstrate that CaMK4 is important in the development of arthritis. Using ex vivo cell cultures from patients with RA, CaMK4 is important for both Th17 generation and osteoclastogenesis. We propose that CaMK4 inhibition represents a new approach to control the development of arthritis.

Infection is one of the major causes of mortality in patients with systemic lupus erythematosus (SLE). We previously found that CD38, an ectoenzyme that regulates the production of NAD+, is up-regulated in CD8+T cells of SLE patients and correlates with the risk of infection. Here, we report that CD38 reduces CD8+T cell function by negatively affecting mitochondrial fitness through the inhibition of multiple steps of mitophagy, a process that is critical for mitochondria quality control. Using a murine lupus model, we found that administration of a CD38 inhibitor in a CD8+T cell–targeted manner reinvigorated their effector function, reversed the defects in autophagy and mitochondria, and improved viral clearance. We conclude that CD38 represents a target to mitigate infection rates in people with SLE.

The complement system is involved in the origin of autoimmunity and systemic lupus erythematosus. Both genetic deficiency of complement components and excessive activation are involved in primary and secondary renal diseases, including lupus nephritis. Among the pathways, the classical pathway has long been accepted as the main pathway of complement activation in systemic lupus erythematosus. However, more recent studies have shown the contribution of factors B and D which implies the involvement of the alternative pathway. While there is evidence on the role of the lectin pathway in systemic lupus erythematosus, it is yet to be demonstrated whether this pathway is protective or harmful in lupus nephritis. Complement is being explored for the development of disease biomarkers and therapeutic targeting. In the current review we discuss the involvement of complement in lupus nephritis.

ImportanceHigher risks of contracting infection, developing severe illness and mortality are known facts in aged and male sex if exposed to the wild type SARS-CoV-2 strains (Wuhan and B.1 strains). Now, accumulating evidence suggests greater involvement of lower age and narrowing the age and sex based differences for the severity of symptoms in infections with emerging SARS-CoV-2 variants. Delta variant (B.1.617.2) is now a globally dominant SARS-CoV-2 strain, however, current evidence on demographic characteristics for this variant are limited. Recently, delta variant caused a devastating second wave of COVID-19 in India. We performed a demographic characterization of COVID-19 cases in Indian population diagnosed with SARS-CoV-2 genomic sequencing for delta variant.ObjectiveTo determine demographic characteristics of delta variant in terms of age and sex, severity of the illness and mortality rate, and post-vaccination infections.DesignA cross sectional studySettingDemographic characteristics, including vaccination status (for two complete doses) and severity of the illness and mortality rate, of COVID-19 cases caused by wild type strain (B.1) and delta variant (B.1.617.2) of SARS-CoV-2 in Indian population were studied.ParticipantsCOVID-19 cases for which SARS-CoV-2 genomic sequencing was performed and complete demographic details (age, sex, and location) were available, were included.ExposuresSARS-CoV-2 infection with Delta (B.1.617.2) variant and wild type (B.1) strain.Main Outcomes and MeasuresThe patient metadata containing details for demographic and vaccination status (two complete doses) of the COVID-19 patients with confirmed delta variant and WT (B.1) infections were analyzed [total number of cases (N) =9500, Ndelta=6238, NWT=3262]. Further, severity of the illness and mortality were assessed in subsets of patients. Final data were tabulated and statistically analyzed to determine age and sex based differences in chances of getting infection and the severity of illness, and post-vaccination infections were compared between wild type and delta variant strains. Graphs were plotted to visualize the trends.ResultsWith delta variant, in comparison to wild type (B.1) strain, higher proportion of lower age groups, particularly Conclusions and RelevanceThe increased involvement of young (0-19 year) and women, lower mean age for contracting infection and symptomatic illness/hospitalization, higher mortality, and frequent incidences of post-vaccination infections with delta variant compared to wild type strain raises significant epidemiological concerns.Key PointsQuestionDid SARS-CoV-2 B.1.617.2 (Delta) variant infections show varied demographic characteristics in comparison to wild type strains?FindingsIn this cross sectional study viral genomic sequences of 9500 COVID-19 patients were analyzed. As the key findings, increased involvement of young (0-19 year) and women, lower mean age for contracting infection and symptomatic illness/hospitalization, higher mortality, and frequent incidences of post-vaccination infections with delta variant in comparison to wild type (WT) strain (B.1) were observed.MeaningThe findings of this study suggest that delta variant has varied demographic characteristics reflecting increased involvement of the young and women, and increased lethality in comparison to wild type strains.

Trauma remains a major cause of death throughout the world, especially for patients younger than 45 years. Due to rapid advances in clinical management, both in the acute and prehospital settings, trauma patients survive devastating injuries at unprecedented rates. However, these patients can often face life threatening complications that stem from the robust innate immune response induced by severe hemorrhage, leading to further tissue injury rather than repair. The complement and coagulation cascades are key mediators in this disordered reaction, which includes the development of trauma‐induced coagulopathy. There is increasing evidence that cross‐talk between these two pathways allows rapid amplification of their otherwise targeted responses and contributes to overwhelming and prolonged systemic inflammation. In this article, we summarize the initial steps of innate immune response to trauma and review the complex complement and coagulation cascades, as well as how they interact with each other. Despite progress in understanding these cascades, effective therapeutic targets have yet to be found and further research is needed both to improve survival rates as well as decrease associated morbidity.

Lung inflammation and damage is prominent in people infected with SARS-Cov-2 and a major determinant of morbidity and mortality. We report the deposition of complement components in the lungs of people who succumbed to COVID-19 consistent with the activation of the classical and the alternative pathways. Our study provides strong rationale for the expansion of trials involving the use of complement inhibitors to treat patients with COVID-19.

Current technologies and available scaffold materials do not support long-term cell viability, differentiation and maintenance of podocytes, the ultra-specialized kidney resident cells that are responsible for the filtration of the blood. We developed a new platform which imitates the native kidney microenvironment by decellularizing fibroblasts grown on surfaces with macromolecular crowding. Human immortalized podocytes cultured on this platform displayed superior viability and metabolic activity up to 28 days compared to podocytes cultured on tissue culture plastic surfaces. The new platform displayed a softer surface and an abundance of growth factors and associated molecules. More importantly it enabled podocytes to display molecules responsible for their structure and function and a superior development of intercellular connections/interdigitations, consistent with maturation. The new platform can be used to study podocyte biology, test drug toxicity and determine whether sera from patients with podocytopathies are involved in the expression of glomerular pathology.

Drug repurposing is the only method capable of delivering treatments on the shortened time-scale required for patients afflicted with lung disease arising from SARS-CoV-2 infection. Mucin-1 (MUC1), a membrane-bound molecule expressed on the apical surfaces of most mucosal epithelial cells, is a biochemical marker whose elevated levels predict the development of acute lung injury (ALI) and respiratory distress syndrome (ARDS), and correlate with poor clinical outcomes. In response to the pandemic spread of SARS-CoV-2, we took advantage of a high content screen of 3,713 compounds at different stages of clinical development to identify FDA-approved compounds that reduce MUC1 protein abundance. Our screen identified Fostamatinib (R788), an inhibitor of spleen tyrosine kinase (SYK) approved for the treatment of chronic immune thrombocytopenia, as a repurposing candidate for the treatment of ALI. In vivo, Fostamatinib reduced MUC1 abundance in lung epithelial cells in a mouse model of ALI. In vitro, SYK inhibition by Fostamatinib promoted MUC1 removal from the cell surface. Our work reveals Fostamatinib as a repurposing drug candidate for ALI and provides the rationale for rapidly standing up clinical trials to test Fostamatinib efficacy in patients with COVID-19 lung injury.

Summary Drug repurposing has the advantage of identifying potential treatments on a shortened timescale. In response to the pandemic spread of SARS-CoV-2, we took advantage of a high-content screen of 3,713 compounds at different stages of clinical development to identify FDA-approved compounds that reduce mucin-1 (MUC1) protein abundance. Elevated MUC1 levels predict the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and correlate with poor clinical outcomes. Our screen identifies fostamatinib (R788), an inhibitor of spleen tyrosine kinase (SYK) approved for the treatment of chronic immune thrombocytopenia, as a repurposing candidate for the treatment of ALI. In vivo, fostamatinib reduces MUC1 abundance in lung epithelial cells in a mouse model of ALI. In vitro, SYK inhibition by the active metabolite R406 promotes MUC1 removal from the cell surface. Our work suggests fostamatinib as a repurposing drug candidate for ALI., Graphical Abstract, Highlights Elevated MUC1 levels predict the development of acute lung injury (ALI) A high-content screen of 3,713 compounds identifies repurposing candidates R406 removes MUC1 from the apical surface of epithelial cells Fostamatinib treatment reduces MUC1 in a mouse model of lung injury, In a high-content screen, Kost-Alimova et al. identify R406, the active metabolite of fostamatinib, as an FDA-approved candidate repurposing compound for the reduction of MUC1 protein levels in lung epithelium in the setting of acute lung injury.

Acute and chronic kidney failure is common in hospitalized patients with COVID-19, yet the mechanism of injury and predisposing factors remain poorly understood. We investigated the role of complement activation by determining the levels of deposited complement components (C1q, C3, FH, C5b-9) and immunoglobulin along with the expression levels of the injury-associated molecules spleen tyrosine kinase (Syk), mucin-1 (MUC1) and calcium/calmodulin-dependent protein kinase IV (CaMK4) in the kidney tissues of people who succumbed to COVID-19. We report increased deposition of C1q, C3, C5b-9, total immunoglobulin, and high expression levels of Syk, MUC1 and CaMK4 in the kidneys of COVID-19 patients. Our study provides strong rationale for the expansion of trials involving the use of inhibitors of these molecules, in particular C1q, C3, Syk, MUC1 and CaMK4 to treat patients with COVID-19.

Intestinal ischemia followed by reperfusion leads to local and remote organ injury attributed to inflammatory response during the reperfusion phase. The extent to which ischemia contributes to ischemia/reperfusion injury has not been thoroughly studied. After careful evaluation of intestinal tissue following 30 min of ischemia, we noticed significant local mucosal injury in wild-type mice. This injury was drastically reduced in C3-deficient mice, suggesting C3 involvement. Depletion of circulating complement with cobra venom factor eliminated, as expected, injury recorded at the end of the reperfusion phase but failed to eliminate injury that occurred during the ischemic phase. Immunohistochemical studies showed that tissue damage during ischemia was associated with increased expression of C3/C3 fragments primarily in the intestinal epithelial cells, suggesting local involvement of complement. In vitro studies using Caco2 intestinal epithelial cells showed that in the presence of LPS or exposure to hypoxic conditions the cells produce higher C3 mRNA as well as C3a fragment. Caco2 cells were also noted to produce cathepsins B and L, and inhibition of cathepsins suppressed the release of C3a. Finally, we found that mice treated with a cathepsin inhibitor and cathepsin B–deficient mice suffer limited intestinal injury during the ischemic phase. To our knowledge, our findings demonstrate for the first time that significant intestinal injury occurs during ischemia prior to reperfusion and that this is due to activation of C3 within the intestinal epithelial cells in a cathepsin-dependent manner. Modulation of cathepsin activity may prevent injury of organs exposed to ischemia.

Tissue engineering by self-assembly uses the cells' secretome as a regeneration template and biological factory of trophic factors. Despite the several advantages that have been witnessed in preclinical and clinical settings, the major obstacle for wide acceptance of this technology remains the tardy extracellular matrix formation. In this study, we assessed the influence of macromolecular crowding (MMC)/excluding volume effect, a biophysical phenomenon that accelerates thermodynamic activities and biological processes by several orders of magnitude, in human corneal fibroblast (HCF) culture. Our data indicate that the addition of negatively charged galactose derivative (carrageenan) in HCF culture, even at 0.5% serum, increases by 12-fold tissue-specific matrix deposition, while maintaining physiological cell morphology and protein/gene expression. Gene analysis indicates that a glucose derivative (dextran sulfate) may drive corneal fibroblasts toward a myofibroblast lineage. Collectively, these results indicate that MMC may be suitable not only for clinical translation and commercialization of tissue engineering by self-assembly therapies, but also for the development of in vitro pathophysiology models.

Aim: Topographically modified substrates are increasingly used in tissue engineering to enhance biomimicry. The overarching hypothesis is that topographical cues will control cellular response at the cell–substrate interface. Materials & methods: The influence of anisotropically ordered poly(lactic-co-glycolic acid) substrates (constant groove width of ˜1860 nm; constant line width of ˜2220 nm; variable groove depth of ˜35, 306 and 2046 nm) on in vitro and in vivo osteogenesis were assessed. Results & discussion: We demonstrate that substrates with groove depths of approximately 306 and 2046 nm promote osteoblast alignment parallel to underlined topography in vitro. However, none of the topographies assessed promoted directional osteogenesis in vivo. Conclusion: 2D imprinting technologies are useful tools for in vitro cell phenotype maintenance.

C3a is important in the regulation of the immune response as well as in the development of organ inflammation and injury. Furthermore, C3a contributes to liver regeneration but its role in intestinal stem cell function has not been studied. We hypothesized that C3a is important for intestinal repair and regeneration. Intestinal organoid formation, a measure of stem cell capacity, was significantly limited in C3-deficient and C3a receptor (C3aR) 1-deficient mice while C3a promoted the growth of organoids from normal mice by supporting Wnt-signaling but not from C3aR1-deficient mice. Similarly, the presence of C3a in media enhanced the expression of the intestinal stem cell marker leucine-rich repeat G-protein-coupled receptor 5 (Lgr5) and of the cell proliferation marker Ki67 in organoids formed from C3-deficient but not from C3aR1-deficient mice. Using Lgr5.egfp mice we showed significant expression of C3 in Lgr5+ intestinal stem cells whereas C3aR1 was expressed on the surface of various intestinal cells. C3 and C3aR1 expression was induced in intestinal crypts in response to ischemia/reperfusion injury. Finally, C3aR1-deficient mice displayed ischemia/reperfusion injury comparable to control mice. These data suggest that C3a through interaction with C3aR1 enhances stem cell expansion and organoid formation and as such may have a role in intestinal regeneration.

Modular tissue engineering is based on the cells’ innate ability to create bottom-up supramolecular assemblies with efficiency and efficacy still unmatched by man-made devices. Although the regenerative potential of such tissue substitutes has been documented in preclinical and clinical setting, the prolonged culture time required to develop an implantable device is associated with phenotypic drift and/or cell senescence. Herein, we demonstrate that macromolecular crowding significantly enhances extracellular matrix deposition in human bone marrow mesenchymal stem cell culture at both 20% and 2% oxygen tension. Although hypoxia inducible factor - 1α was activated at 2% oxygen tension, increased extracellular matrix synthesis was not observed. The expression of surface markers and transcription factors was not affected as a function of oxygen tension and macromolecular crowding. The multilineage potential was also maintained, albeit adipogenic differentiation was significantly reduced in low oxygen tension cultures, chondrogenic differentiation was significantly increased in macromolecularly crowded cultures and osteogenic differentiation was not affected as a function of oxygen tension and macromolecular crowding. Collectively, these data pave the way for the development of bottom-up tissue equivalents based on physiologically relevant developmental processes.

A key challenge of in vitro organogenesis is the development in timely manner tissue equivalents. Herein, we assessed the simultaneous effect of oxygen tension (0.5%, 2% and 20%), foetal bovine serum concentration (0.5% and 10%) and macromolecular crowding (75 μg/ml carrageenan) in human dermal fibroblast culture. Our data demonstrate that cells cultured at 2% oxygen tension, in the presence of carrageenan and at 0.5% serum concentration deposited within 3 days in culture more extracellular matrix than cells grown for 14 days, at 20% oxygen tension, 10% serum concentration and in the absence of carrageenan. These data suggest that optimal oxygen tension coupled with macromolecular crowding are important in vitro microenvironment modulators for accelerated development of tissue-like modules in vitro. Statement of Significance To enable clinical translation and commercialisation of in vitro organogenesis therapies, we cultured human dermal fibroblast at 2% oxygen tension, under macromolecular crowding conditions (75 μg/ml carrageenan) and at low foetal bovine serum concentration (0.5%). Within 3 days in culture, more extracellular matrix was deposited under these conditions than cells grown for 14 days, at 20% oxygen tension, 10% FBS concentration and in the absence of crowding agents. These data bring us closer to the development of more clinically relevant tissue-like modules.

Advancements in molecular and cell biology have led to the development of cell-based therapies to treat injured or degenerated tissues. [1] The rationale of this concept is that functional regeneration can be achieved best by using the innate capacity of cells to create their own tissue-specific extracellular matrix (ECM) avoiding the shortfalls of man-made devices. Although direct cell injections have demonstrated very promising preclinical and clinical outcomes, [2] the mode of administration offers little control over local retention and distribution of the injected cell suspensions[3] leading to scattered therapeutic efficiency. This deficiency has led to the development of living substitutes for skin[4] and blood vessel[5] composed of cells seeded on a collagen scaffold. Notwithstanding the efficacious results in preclinical models and clinical trials, it soon became apparent that the presence of the scaffold hinders tissue remodelling and function. [6] These drawbacks led to the development of the scaffold-free cell-sheet tissue engineering (CSTE)[7] or tissue engineering by self-assembly (TESA), [8] a therapy that offers the fabrication of a contiguous cell sheet that is stabilised by cell-cell contacts and endogenously produced ECM. Despite the documented, in preclinical and clinical setting, positive outcomes for skin, [9] blood vessel, [10, 11] cornea, [12, 13] heart, [14] lung, [15] liver[16] and bone[17] replacement, only Epicel® (Genzyme, USA) for skin and LifeLine™ for blood vessel (Cytograft, USA) have been commercialised so far. This limited technology transfer from bench-top to clinic has been attributed to the substantial long period of time required for ex vivo culture (e.g. 14-35 days for corneal epithelium; [13] 84 days for corneal stromal; [18] 28 days for corneal endothelium;[19] 70 days for lung cell-sheet; [15] and 196 days for blood vessel[11] ) that often leads to loss of native phenotype and cell senescence.[20] Here, we propose a biophysical approach, termed macromolecular crowding (MMC), that increases thermodynamic activities and biological processes by several orders of magnitude,[21] as means to create ECM-rich tissue equivalents. The principle of MMC is derived from the notion that in vivo cells reside in a highly crowded/dense extracellular space and therefore the conversion of the de novo synthesised procollagen to collagen I is rapid. [22] However, in the even substantially more dilute than body fluids (e.g. urine: 36-50g/l; blood: 80g/l) culture conditions (e.g. HAM F10 nutrient medium: 16.55g/l; DMEM/F12 medium: 16.78g/l; DMEM high glucose and L-glutamine medium: 17.22g/l), the rate limiting conversion of procollagen to collagen I is very slow (Figure 1a). We propose that the addition of inert polydispersed macromolecules (presented as spherical objects of variable diameter in Figure 1b) in the culture media will facilitate amplified production of ECM-rich living substitutes. We thank Dr Oliver Carroll for laboratory management; and Mr Maciek Doczyk (http://doczykdesign.com) for his support in the preparation of Figure 1 of this manuscript. This work is supported by Science Foundation Ireland, Research Frontiers Programme, Project Number: SFI‐09‐RFP‐ENM2483 to D.Z.; Science Foundation Ireland, E.T.S. Walton Visitor Awards Programme, Project Number: 08/W.1/B2568 to M.R., A.P. and D.Z.; Health Research Board, Project Number: HRA_POR/2011/84 to D.Z.; and College of Engineering and Informatics, Postgraduate Scholarship Scheme, NUI Galway to P.K. and D.Z. peer-reviewed

Background: Recent studies have demonstrated an association between insulin growth factor (IGF) and insulin growth factor binding protein-3 (IGFBP-III) serum levels and increased risk for various cancers. However, little information is available on clinical implications of the IGF system in Indian patients with cervical cancer. This study explored associations by analyzing their expression profiles in cervical cancer cases. Materials and Methods: Totals of 50 patients with advanced cervical cancer and 40 healthy controls were enrolled. Human papillomavirus (HPV) and cervical biopsy sample were obtained from all participating women. Circulatory levels were estimated by ELISA and the tissue expression was assessed using RT-PCR and Western blotting. Results: Levels of IGF-I and II showed significant increase whereas IGFBP-III showed significant decline in all patients as compared to controls. Spearman correlation analysis between IGFs and HPV status showed significant correlations. Conclusions: We demonstrated elevated circulating levels and tissue expression of IGF-I and IGF-II in advancer cancer cervix patients, as compared with controls, with a converse trend being apparent for IGFBP-III. In future, associations of the IGF system and clinical outcome of cervical cancer patients in post treatment samples might point to significance in disease mapping as a prognostic marker after validation with a larger patient series.

Corrigendum to “Oxidative stress markers and antioxidant levels in normal pregnancy and pre-eclampsia” [Int J Gynecol Obstet 94 (2006) 23–27] J.B. Sharma ⁎, A. Sharma , A. Bahadur , N. Vimala , A. Satyam , S. Mittal a a Department of Obstetrics and Gynaecology, All-India Institute of Medical Sciences, New Delhi, India b Department of Biochemistry, All-India Institute of Medical Sciences, New Delhi, India

Background: The diagnosis of pemphigus vulgaris (PV) and pemphigus foliaceous (PF) rests upon clinical, histological and immunofluorescence features. Enzyme-linked immunosorbent assay (ELISA) test and immunoblot (IB) assay have shown variable sensitivity and specificity. Aims: We compared the utility of ELISA and IB in pemphigus patients. Methods: Sixty-six pemphigus cases (PV-54, PF-12) and 72 controls (other vesicobullous disorders and healthy controls) were inducted. ELISA for anti-Dsg 3 and 1 antibodies and IB assay were performed. Results: On ELISA, both mean anti-Dsg 1 and 3 titers were raised in PV and PF. Mean anti-Dsg 1 in mucocutaneous PV was significantly higher than in mucosal PV and mean anti-Dsg 3 was significantly raised in PV than in PF. Anti-Dsg 1 and 3 in the control group were negative. Sensitivity and specificity of ELISA in PV was 98.14% and 90.5% while in PF it was 91.6% and 61.1%, respectively.On IB in PV, 36 cases (66.67%) showed the 130 kDa and 160 kDa antigen bands, 12 (22.2%) only the 130 kDa and six (11.1%) only the 160 kDa band. Eight of the nine pure mucosal cases (88.8%) showed only the 130 kDa. In PF, only the 160 kDa antigen was detected. These antigens were not identified in the control group. Sensitivity and specificity of IB in PV was 88.9% and 100% and in PF it was 100% and 95.2%, respectively. Conclusion: Both tests could differentiate pemphigus from other dermatoses, including other blistering disorders. ELISA could not make a distinction between PV and PF or between the various clinical phenotypes of PV. IB differentiated between PV and PF and the different clinical variants of PV.