Showing papers by "Richard Bucala published in 2022"

CD74 Ablation Rescues Type 2 Diabetes Mellitus-Induced Cardiac Remodeling and Contractile Dysfunction through Pyroptosis-Evoked Regulation of Ferroptosis.

Abstract: Type 2 diabetes mellitus (T2D) contributes to sustained inflammation and myopathic changes in the heart although the precise interplay between the two remains largely unknown. This study evaluated the impact of deficiency in CD74, the cognate receptor for the regulatory cytokine macrophage migration inhibitory factor (MIF), in T2D-induced cardiac remodeling and functional responses, and cell death domains involved. WT and CD74-/- mice were fed a high fat diet (60% calorie from fat) for 8 weeks prior to injection of streptozotocin (STZ, 35 mg/kg, i.p., 3 consecutive days) and were maintained for another 8 weeks. KEGG analysis for differentially expressed genes (DEGs) reported gene ontology term related to ferroptosis in T2D mouse hearts. T2D patients displayed elevated plasma MIF levels. Murine T2D exerted overt global metabolic derangements, cardiac remodeling, contractile dysfunction, apoptosis, pyroptosis, ferroptosis and mitochondrial dysfunction, ablation of CD74 attenuated T2D-induced cardiac remodeling, contractile dysfunction, various forms of cell death and mitochondrial defects without affecting global metabolic defects. CD74 ablation rescued T2D-evoked NLRP3-Caspase1 activation and oxidative stress but not dampened autophagy. In vitro evidence depicted that high glucose/high fat (HGHF) compromised cardiomyocyte function and promoted lipid peroxidation, the effects were ablated by inhibitors of NLRP3, pyroptosis, and ferroptosis but not by the mitochondrial targeted antioxidant mitoQ. Recombinant MIF mimicked HGHF-induced lipid peroxidation, GSH depletion and ferroptosis, the effects of which were reversed by inhibitors of MIF, NLRP3 and pyroptosis. Taken together, these data suggest that CD74 ablation protects against T2D-induced cardiac remodeling and contractile dysfunction through NLRP3/pyroptosis-mediated regulation of ferroptosis.

Defining Clinical and Immunological Predictors of Poor Immune Responses to COVID-19 mRNA Vaccines in Patients with Primary Antibody Deficiency

Abstract: Immune responses to coronavirus disease 2019 (COVID-19) mRNA vaccines in primary antibody deficiencies (PADs) are largely unknown. We investigated antibody and CD4+ T-cell responses specific for SARS-CoV-2 spike protein (S) before and after vaccination and associations between vaccine response and patients’ clinical and immunological characteristics in PADs. The PAD cohort consisted of common variable immune deficiency (CVID) and other PADs, not meeting the criteria for CVID diagnosis (oPADs). Anti-S IgG, IgA, and IgG subclasses 1 and 3 increased after vaccination and correlated with neutralization activity in HCs and patients with oPADs. However, 42% of CVID patients developed such responses after the 2nd dose. A similar pattern was also observed with S-specific CD4+ T-cells as determined by OX40 and 4-1BB expression. Patients with poor anti-S IgG response had significantly lower levels of baseline IgG, IgA, CD19+ B-cells, switched memory B-cells, naïve CD8+ T-cells, and a higher frequency of EM CD8+ T-cells and autoimmunity compared to patients with adequate anti-S IgG responses. Patients with oPADs can develop humoral and cellular immune responses to vaccines similar to HCs. However, a subset of CVID patients exhibit impairment in developing such responses, which can be predicted by the baseline immune profile and history of autoimmunity.

Interleukin-17 Contributes to Chikungunya Virus-Induced Disease

Abstract: CHIKV has been prevalent in Africa, Asia, and the Indian Ocean Islands for decades. There are currently no clinically approved vaccines or specific antiviral drugs targeting CHIKV. ABSTRACT Alphaviral arthritides caused by mosquito-borne arboviruses such as chikungunya virus (CHIKV) can persist for months after the initial acute disease. Here, we investigated the contribution of interleukin-17 (IL-17), a cytokine involved in chronic autoimmune arthropathies such as rheumatoid arthritis, to the development of alphaviral arthropathy. Sera from CHIKV-infected patients who displayed both acute and chronic disease showed high levels of IL-17, IL-6, IL-21, IL-22, and IL-23, especially during the chronic phase of disease. We sought to validate these findings using a mouse model of CHIKV infection and disease using wild-type and IL-17A-deficient mice. Mice were infected with CHIKV, and joint and muscle tissues were harvested at designated time points. Tissue infiltrates were examined by immunohistochemistry, and tissue mRNA and protein expression of cytokines was assessed. Joint and muscle pathology was assessed using histology. CHIKV-infected mice lacking IL-17A showed reduced tissue inflammation and neutrophil infiltration, compared to wild-type mice. These investigations showed a role for IL-17 in the acute phase of CHIKV infection and also during the postacute disease resolution phase. IMPORTANCE CHIKV has been prevalent in Africa, Asia, and the Indian Ocean Islands for decades. There are currently no clinically approved vaccines or specific antiviral drugs targeting CHIKV. The upregulation of IL-17 detected in CHIKV disease patients and the reduced disease seen in IL-17-deficient mice suggest a correlation between IL-17 signaling pathways and CHIKV-induced arthritic inflammation. With an established role in contributing to the pathogenesis of immune-mediated diseases, such as psoriatic arthritis and rheumatoid arthritis, IL-17 signaling plays an important role in alphavirus arthritides.

Bladder Oxidative Stress and HMGB1 Release Contribute to PAR4-Mediated Bladder Pain in Mice

Abstract: Activation of intravesical PAR4 receptors leads to bladder hyperalgesia (BHA) through release of urothelial macrophage migration inhibitory factor (MIF) and urothelial high mobility group box-1 (HMGB1). MIF deficiency and/or MIF antagonism at the bladder block BHA in mice yet the mechanisms are not clear. Since oxidative stress and ERK phosphorylation are involved in MIF signaling we hypothesized that oxidative stress and/or ERK signaling, activated by MIF release, promote intravesical HMGB1 release to induce BHA. We induced BHA by intravesical PAR4 infusion in female C57BL/6 mice. Mechanical sensitivity was evaluated by measuring abdominal von Frey (VF) 50% thresholds before (baseline) and 24 h post-infusion. Intravesical pre-treatment (10 min infusion prior to PAR4) with N-acetylcysteine amide (NACA; reactive-oxygen species scavenger; 3 mg in 50 μl), FR180204 (selective ERK1/2 inhibitor; 200 μg in 50 μl), ethyl pyruvate (EP; HMGB1 release inhibitor; 600 μg in 50 μl), or diluent controls (50 μl) tested the effects of pre-treatment on PAR4-induced BHA. Intravesical fluid was collected after each treatment and HMGB1 concentration was measured using ELISA. Awake micturition parameters (volume and frequency) were assessed at the end of the experiments. Bladders were collected and examined for histological signs of edema and inflammation. Pre-treatment with PBS followed by PAR4 induced BHA in mice but PBS followed by scrambled peptide did not. Pre-treatment with NACA or EP partially blocked PAR4-induced BHA while FR180204 had no effect. A significant correlation between intravesical HMGB1 levels and 50% VF thresholds was observed. All PAR4 treated groups had increased levels of HMGB1 in the intravesical fluid compared to PBS-Scrambled group although not statistically significant. No significant effects were noted on awake micturition volume, micturition frequency or histological evidence of bladder edema or inflammation. Our results show that intravesical antagonism of bladder reactive-oxygen species accumulation was effective in reducing PAR4-induced bladder pain. The correlation between intravesical levels of HMGB1 and bladder pain indicates that released HMGB1 is pivotal to bladder pain. Thus, modulating events in the MIF signaling cascade triggered by PAR4 activation (including bladder oxidative stress and HMGB1 release) warrant further investigation as possible therapeutic strategies.

MIF is a Common Genetic Determinant of COVID-19 Symptomatic Infection and Severity

Abstract: Abstract Background Genetic predisposition to COVID-19 may contribute to its morbidity and mortality. Because cytokines play an important role in multiple phases of infection, we examined whether commonly occurring, functional polymorphisms in macrophage migration inhibitory factor (MIF) are associated with COVID-19 infection or disease severity. Aim To determine associations of common functional polymorphisms in MIF with symptomatic COVID-19 or its severity. Methods This retrospective case control study utilized 1171 patients with COVID-19 from three tertiary medical centers in the United States, Hungary, and Spain, together with a group of 637 pre-pandemic, healthy control subjects. Functional MIF promoter alleles (-794 CATT5-8, rs5844572), serum MIF and soluble MIF receptor levels, and available clinical characteristics were measured and correlated with COVID-19 diagnosis and hospitalization. Experimental mice genetically engineered to express human high- or low-expression MIF alleles were studied for response to coronavirus infection. Results In patients with COVID-19, there was a lower frequency of the high-expression MIF CATT7 allele when compared to healthy controls (11% vs. 19%, OR: 0.54 [0.41, 0.72], p < 0.0001). Among inpatients with COVID-19 (n = 805), there was a higher frequency of the MIF CATT7 allele compared to outpatients (n = 187) (12% vs. 5%, OR: 2.87 [1.42, 5.78], p = 0.002). Inpatients presented with higher serum MIF levels when compared to outpatients or uninfected healthy controls (87 ng/ml vs. 35 ng/ml vs. 29 ng/ml, p < 0.001, respectively). Among inpatients, circulating MIF concentrations correlated with admission ferritin (r = 0.19, p = 0.01) and maximum CRP (r = 0.16, p = 0.03) levels. Mice with a human high-expression MIF allele showed more severe disease than those with a low-expression MIF allele. Conclusions In this multinational retrospective study of 1171 subjects with COVID-19, the commonly occurring -794 CATT7 MIF allele is associated with reduced susceptibility to symptomatic SARS-CoV-2 infection but increased disease progression as assessed by hospitalization. These findings affirm the importance of host genetics in different stages of COVID-19 infection.

Targeting fibrocytes in autoimmunity

Abstract: Thyroid-associated ophthalmopathy, also known as Graves’ ophthalmopathy, is a proliferative disorder of the orbit of the eye with an autoimmune etiology. Disease arises from the enlargement of the extraocular muscles, adipose, and the associated connective tissue that, if untreated, leads to a compressive optic neuropathy and blindness. In Graves’ disease, hyperthyroidism develops from autoantibodies directed against the thyroid-stimulating hormone receptor (TSHR) expressed on the follicular endothelial cells of the thyroid gland. Anti-TSHR autoantibodies stimulate the excessive production of thyroid-stimulating hormone, which in turn leads to the clinical manifestations of hyperthyroidism: thyroid gland enlargement, weight loss, tremor, palpitations, dermopathy, and, in up to 30% of subjects, autoimmune inflammation of the orbital structures (1). In PNAS, Fernando et al. provide evidence for a proximal and central role for the circulating fibrocyte in Graves’ ophthalmopathy pathogenesis (2). The autoimmune diseases comprise at least 100 nosologically distinct entities that afflict as many as 5% of the US population (3). Autoimmunity can be organ specific, as in the case of an autoantibody

Clinical features and high-risk indicators of central nervous system involvement in primary Sjögren’s syndrome

Abstract: Evidence for central nervous system involvement in primary Sjögren's syndrome (pSS) patients is controversial and extremely limited. We aimed to describe the clinical profiles and high-risk indicators of primary Sjögren's syndrome (pSS) patients with central nervous system (CNS) involvement (pSS-CNS).A total of 412 participants with pSS from a hospital in China from January 2012 to December 2019 were enrolled in the retrospective study. 42 pSS-CNS patients were compared with 370 pSS patients without CNS involvement. The clinical features, laboratory examinations, imaging characteristics, and treatment of the pSS-CNS cases were systematically analyzed. Potential risk factors related to pSS-CNS patients were identified by multivariate logistic regression analysis.The prevalence of central nervous system involvement in the studied pSS patients was 10.2% (42/412), with 31.3% (14/42) of pSS patients having neurological manifestations as the initial symptom. The manifestations of hemiparesis (35.7%, 15/42), paraparesis (28.6%, 12/42), dysphonia (31.0%, 13/42), blurred vision (21.4%, 9/42), and dysfunctional proprioception (23.8%, 10/42) were more common in the pSS-CNS patients. Cerebral infarction (57.1%, 24/42), demyelination (31.0%, 13/42), myelitis (23.8%, 11/42), and angiostenosis (21.4%, 9/42) were most often found on MRI or CT scan imaging in the pSS-CNS patients. Intrathecal IgG level and total protein of cerebrospinal fluid were increased in 50% (8/16) of the pSS-CNS group. In comparison with patients without CNS involvement, the pSS-CNS patients were found to also have kidney and lung involvement, hematologic abnormalities, positive ANA and anti-SSA antibody tests, and reduced complement 3 (C3) and complement 4 (C4) levels (all p < 0.05). The prevalence of lung involvement, immune thrombocytopenia, and high-titer ANA (1:1000) were significantly higher in pSS-CNS disease activity compared to those in the moderately active group. Multivariate analysis identified lung involvement, anti-SSA positivity, and low C3 levels as prognostic factors for pSS-CNS. After high-dose glucocorticoids and immunosuppressive therapy, 60.5% (26/38) of pSS-CNS patients improved, 36.8% (14/38) were unresponsive to treatment, and 2.6% (1/38) died.Clinical features are diverse in pSS-CNS patients, and the morbidity rate is low. CNS involvement was the initial presentation in state percentage here pSS patients. Pulmonary involvement, a positive anti-SSA antibody test, and reduced C3 levels are potential risk factors for CNS involvement in pSS. Treatment with high-dose glucocorticoids and immunosuppressive therapy appeared effective in 60% of pSS-CNS patients. Key Points • The CNS manifestations of pSS are diverse, and CNS imaging and CSF analysis are important for the diagnosis. • Pulmonary involvement, positive anti-SSA, and reduced C3 levels are potential risk factors of pSS-CNS. • About 60% of pSS-CNS patients were responsive to high-dose glucocorticoid administration and immunosuppressive therapy.

Managing COVID-19 going forward—the lessons from history

Abstract: Managing COVID-19 going forward—the lessons from history R. Bucala, G. Friedland and F. M. Snowden From the Department of Medicine, Yale School of Medicine, New Haven, CT, USA, Department of Pathology, Yale School of Medicine, New Haven, CT, USA, Department of Epidemiology & Public Health, Yale School of Medicine, New Haven, CT, USA and Department of History and History of Medicine, Yale University, New Haven, CT, USA

Mindfulness-based stress reduction may decrease stress, disease activity, and inflammatory cytokine levels in patients with autoimmune hepatitis

Abstract: Psychological and life stressors may impact autoimmune hepatitis (AIH) disease activity and increase relapse risk. Mindfulness-based stress reduction (MBSR) is a validated course that reduces stress reactivity, and improves stress and emotion regulation. This single-arm exploratory pilot study of adult patients with AIH aimed to define the impact of an 8-week MBSR program on quality of life, disease activity, and cytokine mediators.The perceived stress survey-10 (PSS) and the brief self-control scale (BSCS) measured subjective distress and self-control. Serum alanine aminotransferase (ALT) and cytokine levels were measured, and immunosuppressant doses recorded.Seventeen patients completed the MBSR program. Post-MBSR, 71% (n = 12) showed PSS score improvement at 8 weeks vs. baseline (median 15 vs. 21, p = 0.02). At 12 months, PSS improvement persisted vs. baseline (median 15 vs. 21, p = 0.02). Post-MBSR, 71% (n = 12) showed BSCS score improvement at 8 weeks vs. baseline (median 4.1 vs. 3.8, p = 0.03). At 12 months, the median BSCS score remained significant (3.9 vs. 3.8, p = 0.03). After the 8-week MBSR, the 35% of patients with ALT >34 U/L had a median ALT reduction (44.5 vs. 71.5 U/L, p = 0.06), whereas the 71% of patients on prednisone had significant dose reductions (5.75 vs. 10 mg, p = 0.02) which persisted at 12 months vs. baseline (3.75 vs. 10 mg, p = 0.02) without a compensatory increase in steroid-sparing dosing. Significant improvement was noted in peripheral blood cytokine levels (IL-6, IL-8, IL-10, IL-17, IL-23, and sCD74/MIF ratio) from baseline to 8 weeks.MBSR significantly improved perceived stress and self-control scores while decreasing ALT levels, steroid requirements, and inflammatory cytokine levels in this pilot study in adult AIH. Stress modification may impact quality of life and disease activity, and should be further evaluated as an intervention in AIH.This study is registered at ClinicalTrials.gov (NCT02950077).Autoimmune hepatitis can reduce quality of life and mental health, while stress may impact autoimmune hepatitis itself. We piloted mindfulness-based stress reduction as a strategy to reduce stress in adult patients with autoimmune hepatitis and found that the intervention reduced perceived stress and may have also impacted the disease by improving inflammation and medication needs. Stress reduction should be further studied to improve quality of life and possibly to impact disease activity in autoimmune hepatitis.

“Altered CD8+ T cell associated aging gene signature in the peripheral blood of patients with Alzheimer’s disease”

Abstract: INTRODUCTION Effector memory (EM) CD8+ T cells have been associated with poor cognition in Alzheimer’s disease (AD). Our lab recently discovered an age-associated gene expression signature of IL-7 receptor alpha (IL-7Rα)low EM CD8+ T cells. We hypothesized that individuals with AD have altered levels of this IL-7Rαlow aging gene expression. METHODS Forty genes associated with IL-7Rαlow EM CD8+ T cells, AD, or memory, were analyzed in peripheral blood of participants with normal cognition, mild cognitive impairment, and dementia by qPCR. RESULTS Of the eight genes that were found to be differentially expressed based on clinical diagnosis, 5 genes (62.5%) were IL-7Rαlow aging genes. Principal component analysis revealed 3 clusters of participants with dementia which had distinct expression levels of IL-7Rαlow aging genes and cognitive function. DISCUSSION Our findings support the possible relationship of the IL-7Rαlow EM CD8+ T cell aging signature with cognition in individuals with dementia due to AD.

The MIF SNP rs755622 is a germline determinant of tumor immune activation in Glioblastoma

Abstract: While immunotherapies have shown durable responses for multiple tumors, their efficacy remains limited in some advanced cancers, including glioblastoma. This may be due to differences in the immune landscape, as the glioblastoma microenvironment strongly favors immunosuppressive myeloid cells, which are linked to an elevation in immune-suppressive cytokines, including macrophage migration inhibitory factor (MIF). We now find that a single-nucleotide polymorphism (SNP) rs755622 in the MIF promoter associates with increased leukocyte infiltration in glioblastoma. Furthermore, we identified lactotransferrin expression as being associated with the rs755622 SNP, which could also be used as a biomarker for immune infiltrated tumors. These findings provide the first example in glioblastoma of a germline SNP that underlies differences in the immune microenvironment and identifies high lactotransferrin as a potential factor promoting immune activation.

Arthritis & Rheumatology: “Mid‐Term” Report

Abstract: As the current Arthritis & Rheumatology ( A&R ) editorial team approaches halfway into our 5-year term, we took stock of what is working and where we can make improvements. COVID-19 and COVID-19 manuscripts dominated the lives of our authors, reviewers, and editors for much of year 1 of the term. With many investigators out of the research setting, articles were fi nished and submitted, leading to a 50% increase in submissions for the fi rst 6 months of our term. An amazing editorial team, staff, and academic editors handled the “ surge ” with characteristic grace. We balanced the need to publish COVID-19 work quickly with the requirement for scienti fi c rigor, and only time will tell if A&R succeeded in achieving balance.

Macrophage Migration Inhibitory Factor (MIF) Promotes Increased Proportions of the Highly Permissive Th17-like Cell Profile during HIV Infection

Abstract: In this study, we evaluate the role of the MIF/CD74 axis in the functionality of CD4+ T lymphocytes (CD4TL) during HIV infection. MDMs from healthy donors were infected with a R5-tropic or Transmitted/Founder (T/F) HIV strain. At day 11 post-MDM infection, allogeneic co-cultures with uninfected CD4TLs plus MIF stimulus were performed. Cytokine production was evaluated by ELISA. MIF plasma levels of people with HIV (PWH) were evaluated by ELISA. The phenotype and infection rate of CD4TLs from PWH were analyzed after MIF stimulus. Intracellular cytokines and transcription factors were evaluated by flow cytometry. Data were analyzed by parametric or non-parametric methods. The MIF stimulation of HIV-infected MDMs induced an increased expression of IL-6, IL-1β and IL-8. In CD4TL/MDM co-cultures, the MIF treatment increased IL-17A/RORγt-expressing CD4TLs. Higher concentrations of IL-17A in supernatants were also observed. These results were recapitulated using transmitted/founder (T/F) HIV-1 strains. The MIF treatment appeared to affect memory CD4TLs more than naïve CD4TLs. MIF blocking showed a negative impact on IL17A+CD4TL proportions. Higher MIF concentrations in PWH-derived plasma were correlated with higher IL-17A+CD4TL percentages. Finally, MIF stimulation in PWH-derived PBMCs led to an increase in Th17-like population. MIF may contribute to viral pathogenesis by generating a microenvironment enriched in activating mediators and Th17-like CD4TLs, which are known to be highly susceptible to HIV-1 infection and relevant to viral persistence. These observations establish a basis for considering MIF as a possible therapeutic target.