A Case of X-Linked Moesin-Associated Immune Deficiency in a Pediatric Patient

Background: X-Linked Moesin-Associated Immune Deficiency (X-MAID) is a rare severe combined immunodeficiency (SCID) subtype that can present at any age due to its variability. Depending on severity, patients demonstrate failure to thrive, recurrent bacterial and viral infections, and increased susceptibility to varicella zoster. It has been characterized by marked lymphopenia with hypogammaglobulinemia and impaired T-cell migration and proliferation. Case Presentation: This is a report of a Cuban 7-year-old male with poor weight gain and facial dysmorphia. He had a history of recurrent bacterial gastrointestinal infections and pneumonia beginning at 4 months of age. He additionally had 4-6 upper respiratory tract and ear infections annually. While still living in Cuba, he was admitted for a profound EBV infection in the setting of significant leukopenia. A bone marrow biopsy confirmed no malignancy. After he moved to the United States, his laboratory work-up revealed marked leukopenia with low absolute neutrophil and lymphocyte count with low T and B cells, very low immunoglobulin levels IgG, IgA, and IgM, and poor vaccination responses to streptococcus pneumonia, varicella zoster, and SARS-CoV-2. Genetic testing revealed a missense pathogenic variant c.511C>T (p.Arg171Trp) in the moesin (MSN) gene associated with X-MAID. He was managed with Bactrim and acyclovir prophylaxis, and immunoglobulin replacement therapy, and considered for hematopoietic stem cell transplantation. Discussion(s): Diagnosis of X-MAID should be considered in patients with recurrent infections and profound lymphopenia. As with SCID, early diagnosis and intervention is of utmost importance to prevent morbidity and mortality. This case demonstrates the importance of genetic testing in identifying this disease as it may prompt an immunologist to consider HSCT if conservative management is suboptimal. In the current literature, HSCT appears promising, but the long-term outcomes have yet to be described.Copyright © 2023 Elsevier Inc.

Characterization of Adaptive Immune Responses to SARS-CoV-2 Updated Bivalent Booster

Bivalent COVID-19 vaccines that contain two mRNAs encoding Wuhan-1 and Omicron BA.4/5 spike proteins are successful in preventing infection from the original strain and Omicron variants, but the quality of adaptive immune responses is still not well documented. This study aims at characterizing adaptive immune responses to the bivalent booster vaccination in 46 healthy participants. Plasma and PBMC were collected prior and three weeks after bivalent booster. We measured anti-N, anti-S, and RBD IgM, IgA, IgG plasma titers against original, Omicron BA.1, and BA.5 variants (pending) as well as total anti-S IgG titers and surrogate Virus Neutralization capacity against the Alpha, Delta, and BA.1 variant. With spectral flow-cytometry we identified peripheral blood B-cells specific for the RBD of the S-protein of the original and BA.1 variants. T-cell-specific responses were assessed by cytokine release assay after stimulation with SARS-CoV-2 peptides from the original, BA.1, BA.4, and BA.5 variants (pending). Finally, we performed TRB and IGH repertoire studies on sorted CD4+, CD8+, CD19+ lymphocytes, to study breadth of SARS-CoV-2 specific clonotypes (pending). 27/46 participants were analyzed;9 had SARS-CoV-2 infection (COVID+), while 18 are infection naive (COVID-). In both groups, median time since last dose of SARS-CoV-2 vaccine (3rd or 4th) was 11 months. All subjects were positive for anti-S IgG prior to bivalent booster. The COVID + group displayed anti-S IgG pre-booster levels and neutralization against BA.1 higher than the COVID- group. Significant increase post-boost of total anti-S IgG and BA.1 neutralizing activity was detected in the COVID- but not in the COVID+ group;however, no difference in neutralization activity post-boost was detected between the two groups. Furthermore, the COVIDgroup showed significant increase in the frequency of CD19+ and CD27+ switched memory B-cells specific for BA.1 RBD in post-boost compared to pre-boost samples. However, post-boost frequencies of the same B-cells were higher in the COVID+ compared to the COVID- group. These preliminary findings confirm that among individual immunized with the original COVID-19 mRNAvaccine, prior COVID infection provides increased protection against SARS-CoV-2 variants. They also demonstrate that booster immunization with the bivalent vaccine induces robust adaptive immune responses against Omicron variant.[Formula presented][Formula presented]Copyright © 2023 Elsevier Inc.

Association of SARS-COV-2 viral RNAemia, IL- 6 gene polymorphism, serum IL-6 and peripheral blood lymphocytes and monocytes with disease severity in COVID-19 patients

Coronavirus disease 2019 (COVID-19) is a fatal pandemic viral disease caused by the severe acute respiratory syndrome corona virus type-2 (SARS-CoV-2). The aim of this study is to observe the associations of IL-6, SARS-COV-2 viral load (RNAemia), IL- 6 gene polymorphism and lymphocytes and monocytes in peripheral blood with disease severity in COVID-19 patients. This study was carried out from March 2021 to January 2022. RT-PCR positive 84 COVID-19 patients and 28 healthy subjects were enrolled. Blood was collected to detect SARS-COV-2 viral RNA (RNAemia) by rRT-PCR, serum IL-6 level by chemiluminescence method, SNPs of IL-6 by SSP-PCR, immunophenotyping of lymphocytes and monocyte by flow cytometry. Serum IL-6 level (pg/ml) was considerably high among critical patients (102.02 +/- 149.7) compared to severe (67.20 +/- 129.5) and moderate patients (47.04 +/- 106.5) and healthy controls (3.5 +/- 1.8). Serum SARS-CoV-2 nucleic acid positive cases detected mostly in critical patients (39.28%) and was correlated with extremely high IL-6 level and high mortality (R =.912, P < 0.001). Correlation between IL-6 and monocyte was statistically significant with disease severity (severe group, p < 0.001, and 0.867*** and critical group p < 0.001 and 0.887***). In healthy controls, moderate, severe and critically ill COVID-19 patients, IL-6 174G/C (rs 1800795) GG genotype was 82.14%, 89.20%, 67.85% and 53.57% respectively. CC and GC genotype had strong association with severity of COVID-19 when compared with GG genotype. Significant statistical difference found in genotypes between critical and moderate groups (p < 0.001, OR-10.316, CI-3.22-23.86), where CC genotype was associated with COVID-19 severity and mortality. The absolute count of T cell, B cell, NK cell, CD4+ T cells and CD8+ T cells were significantly decreased in critical group compared to healthy, moderate and severe group (P < 0.001). Exhaustion marker CD94/NKG2A was increased on NK cells and CD8+ cytotoxic T cell among critical and severe group. Absolute count of monocyte was significantly increased in critical group (P < 0.001). Serum IL-6, IL-6 174 G/C gene and SARS-CoV-2 RNAaemia can be used in clinical practice for risk assessment;T cell subsets and monocyte as biomarkers for monitoring COVID-19 severity. Monoclonal antibody targeting IL-6 receptor and NKG2A for therapeutics may prevent disease progression and decrease morbidity and mortality.Copyright © 2023 Elsevier Inc.

IRF2BP2 mutation with autoimmune enteropathy, immune deficiency, and respiratory failure

Case history: We present the case of a 31-year-old Hispanic male with history of recurrent bronchiectasis, invasive aspergillosis, and severe persistent asthma, who is now status post lung transplant for end-stage lung disease. He initially presented at 7 years of age with diarrhea, failure to thrive, and nearly absent immunoglobulin levels (IgG < 33 mg/dL, IgA < 7 mg/dL, IgM = 11 mg/dL, IgE = 4 IU/dL) necessitating IVIG treatment. Small intestinal biopsy showed villous atrophy consistent with autoimmune enteropathy. Sweat chloride was reported as indeterminate (44 me/dL). Initial WBC, platelet, and T- and NK-cell counts were within normal range, and B-cell count and percentage were borderline low. Most recently, he was found to have increased immature B-cell count (CD21low), decreased memory B-cells, and poor pneumococcal vaccine antibody response. Patient has been hospitalized numerous times with increasingly severe bronchiectasis, pneumonitis, and COVID-19 infections twice despite vaccination, leading to respiratory failure and lung transplantation. Family history is negative for immune deficiency and lung diseases. Discussion(s): Of these 3 VUSs (see the table), the one in IRF2BP2 has the most pathogenic potential due to its autosomal dominant inheritance, its location in a conserved domain (Ring), and previous case reports of pathogenic variants at the same or adjacent alleles 1-3. Baxter et al reported a de novo truncating mutation in IRF2BP2 at codon 536 (c.1606CinsTTT), which is similar to our patient's mutation. This patient was noted to have an IPEX-like presentation, with chronic diarrhea, hypogammaglobulinemia, and recurrent infections. Variant Functional Prediction Score for our variant predicts a potentially high damage effect. There are 2 other case reports of heterozygous mutations in loci adjacent to this allele;one (c.1652G>A)2 with a similar clinical phenotype to our patient and the other (C.625-665 del)3 with primarily inflammatory features and few infections. Impact: This case highlights a variant in IRF2BP2 associated with severe hypogammaglobulinemia, recurrent pulmonary infections, and autoimmune enteropathy. [Table presented]Copyright © 2023 Elsevier Inc.

COVID-19-Related Encephalitis in a Child with PIK3CD Defect

Introduction: COVID-19 related encephalitis has been reported in pediatric patients;however, there are no reports in patients with inborn errors of immunity (IEI). Activated PI3K Delta Syndrome (APDS) is a disease of immune dysregulation with immunodeficiency, autoimmunity, and abnormal lymphoproliferation resulting from autosomal dominant gain-offunction variants in PIK3CD or PIK3R1 genes. We investigate a family with APDS, one mother and three children, one of whom developed COVID-19 related encephalitis. Method(s): Patients were consented to an IRB-approved protocol at our institution. Medical records and detailed immunophenotyping were reviewed. Family members were sequenced for IEI with a targeted gene panel. Result(s): The index case is a 10-year-old female with a known pathogenic variant in PIK3CD (c.3061 G > A, p.Glu1021Lys), who contracted SARS-COV-2 despite one COVID-19 vaccination in the series. Her disease course included COVID-related encephalitis with cerebellitis and compression of the pons, resulting in lasting truncal ataxia and cerebellar mutism. At that time, the patient was not on immunoglobulin replacement therapy (IgRT), but was receiving Sirolimus. Besides the index case, 3 family members (2 brothers, 1 mother) also share the same PIK3CD variant with variable clinical and immunological phenotypes. All children exhibited high transitional B-cells, consistent with developmental block to follicular B cell stage. Increased non-class switched IgM+ memory B cells and skewing towards CD21lo B cell subset, which is considered autoreactive-like, was observed in all patients. Of note, the patient had low plasmablasts, but normal immunoglobulins. Of her family members, only one was receiving both sirolimus and IgRT. Conclusion(s): We describe a rare case of COVID-19-related encephalitis in a patient with inborn error of immunity while not on IgRT. This may indicate infection susceptibility because of a lack of sufficient immunity to SARS-CoV-2, unlike the rest of her family with the same PIK3CD variant.Copyright © 2023 Elsevier Inc.

Boosting the Immune System with Vitamin D: Special Focus on Prevention of COVID-19 and Complications

In addition to the classical functions of the musculoskeletal system and calcium homeostasis, the function of vitamin D as an immune modulator is well established. The vitamin D receptors and enzymes that metabolize vitamin D are ubiquitously expressed in most cells in the body, including T and B lymphocytes, antigen-presenting cells, monocytes, macrophages and natural killer cells that trigger immune and antimicrobial responses. Many in vitro and in vivo studies revealed that vitamin D promotes tolerogenic immunological action and immune modulation. Vitamin D adequacy positively influences the expression and release of antimicrobial peptides, such as cathelicidin, defensin, and anti-inflammatory cytokines, and reduces the expression of proinflammatory cytokines. Evidence suggestss that vitamin D's protective immunogenic actions reduce the risk, complications, and death from COVID-19. On the contrary, vitamin D deficiency worsened the clinical outcomes of viral respiratory diseases and the COVID-19-related cytokine storm, acute respiratory distress syndrome, and death. The study revealed the need for more preclinical studies and focused on well-designed clinical trials with adequate sizes to understand the role of vitamin D on the pathophysiology of immune disorders and mechanisms of subduing microbial infections, including COVID-19.Copyright © 2023 Bentham Science Publishers.

T-cell mediated response to emerging COVID19 strains in patients with cancer studied via deep learning

Cancer patients, particularly those receiving B cell-depleting therapy for lymphoid malignancies, are at risk of prolonged SARS-CoV-2 infection, poorer clinical outcomes, and delayed initiation or disruption of cancer-directed therapy (Lee at al., 2022, Clark et al., 2021). We first studied T-cell mediated response to the Wuhan strain of SARS-CoV-2 in a cohort of 69 patients with hematologic and solid cancers, including 18 patients who received prior B-cell depleting therapy. Patients with prolonged COVID-19 clearance, defined by a positive PCR test for longer than 30 days, had a broad but poorly converged CD8+ dominant response and a lacking CD4+ response. To conduct this analysis, we performed bulk T-cell receptor (TCR) sequencing of 121 blood samples and tracked over time TCR repertoire statistics such as clonality, convergence, breadth, and depth of COVID-19-associated TCRs during the active and convalescent periods of COVID-19 infection. These SARS-CoV-2-associated TCRs were identified leveraging immunoSEQ T-MAP database (Snyder et al., 2020), a set of TCR sequences derived from COVID-19 patients and experimentally identified as responsive to MHC Class I and II epitopes from the Wuhan SARS-CoV-2 strain using the multiplex identification of TCR antigen assay (Klinger et al., 2015). To extend our TCR repertoire analysis to other SARS-CoV-2 variants, including Omicron, we developed a deep learning (DL) method to predict TCR specificities for new SARS-CoV-2 epitopes. This DL approach also permits the identification of SARS-CoV2-responsive TCRs private to an individual. Combining this DL approach with our TCR statistics methodology, we studied the dynamics of T-cell response to COVID-19 vaccinations in a cohort of 50 patients with cancer and analyzed TCR repertoire characteristics associated with different degrees of COVID-19 severity in a cohort of 42 cancer patients who contracted the Omicron. Understanding cellular response to novel infections is critical for patient care in the context of cancer, and our novel DL-based approach can leverage existing datasets to analyze and track response to emerging viral strains.

Altered immune response to vaccination in patients with plasma cell premalignancy

Introduction Patients with hematological malignancies, including multiple myeloma (MM), experience suboptimal responses to SARS-CoV-2 vaccination. Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smoldering Multiple Myeloma (SMM) are precursors to MM and exhibit altered immune cell composition and function. The SARS-CoV-2 pandemic and the subsequent population-wide vaccination represent an opportunity to study the real-life immune response to a common antigen. Here, we present updated results from the IMPACT study, a study we launched in November 2020 to characterize the effect of plasma cell premalignancy on response to SARS-CoV2 vaccination (vx). Methods We performed: (i) ELISA for SARS-CoV-2-specific antibodies on 1,887 peripheral blood (PB) samples (237 healthy donors (HD), and 550 MGUS, 947 SMM, and 153 MM patients) drawn preand post-vx;(ii) single-cell RNA, T cell receptor (TCR), and B cell receptor (BCR) sequencing (10x Genomics) on 224 PB samples (26 HD, and 20 MGUS, 48 SMM, and 24 MM patients) drawn preand post-vx;(iii) plasma cytokine profiling (Olink) on 106 PB samples (32 HD, and 38 MGUS and 36 SMM patients) drawn pre- and post-vx;and (iv) bulk TCR sequencing (Adaptive Biotechnologies) on 8 PB samples from 4 patients (2 MGUS, 2 SMM) drawn pre- and post-vx. Results Patients with MGUS and SMM achieved comparable antibody titers to HD two months post-vx. However, patient titers waned significantly faster, and 4 months post-vx we observed significantly lower titers in both MGUS (Wilcoxon rank-sum, p=0.030) and SMM (p=0.010). These results indicate impaired humoral immune response in patients with MGUS and SMM.At baseline, the TCR repertoire was significantly less diverse in patients with SMM compared to HD (Wilcoxon rank-sum, p=0.039), while no significant difference was observed in the BCR repertoire (p=0.095). Interestingly, a significant increase in TCR repertoire diversity was observed post-vx in patients with SMM (paired t-test, p=0.014), indicating rare T cell clone recruitment in response to vaccination. In both HD and patients, recruited clones showed upregulation of genes associated with CD4+ naive and memory T cells, suggesting preservation of the T cell response in SMM, which was confirmed by bulk TCR-sequencing in 4 patients.Lastly, by cytokine profiling, we observed a defect in IL-1beta and IL-18 induction post-vx in patients with SMM compared to HD (Wilcoxon rank-sum, p=0.047 and p=0.015, respectively), two key monocyte-derived mediators of acute inflammation, suggesting an altered innate immune response as well. Conclusion Taken together, our findings highlight that despite the absence of clinical manifestations, plasma cell premalignancy is associated with defects in both innate and adaptive immune responses. Therefore, patients with plasma cell premalignancy may require adjusted vaccination strategies for optimal immunization.

Retrospective Study on Vaccine Responses and Natural Course of COVID-19 Infections in Primary Immunodeficiency

We conducted a retrospective study in the adult primary immunodeficiency clinic at UAB examining COVID-19 infection and COVID-19 antibody response from vaccination, natural infection, and immunoglobulin replacement from February 2021 to November 2022. Our goal was to determine if nucleocapsid and spike antibodies could be found in our PID patients and if these antibodies could be derived from natural infection, vaccination, or antibody replacement exclusively or combinatory. We hypothesized that increasing antibodies would be detected in our population as the COVID period extended. Two hundred and forty-five subjects were tracked over 336 clinic visits during this period. Our PID population included subjects with CVID, XLA, thymoma, hypogammaglobulinemia, IgA deficiency, IgG subclass deficiency, specific antibody deficiency, Down syndrome, IgM deficiency, and patients with recurrent sinopulmonary infections. We had 196 females and 45 males in our study. In our patient population, 47% of our patient had known COVID-19 infection. Of those 47%, 21% of those infected patients had COVID-19 at least twice. Of those infected, three did not have COVID-19 spike antibodies and chose not to get vaccinated either. Two of those patients were not on IVIG and one was on Pangyza. Of those infected, 70% (n = 80) were on IgG infusions compared to those uninfected, 77% (n = 96) were on IgG infusions. Of interest, we had three XLA patients and all three had COVID-19 infection in the summer 2021. Two of them tested positive for nucleocapsid and spike antibodies in high titers and they were receiving Gammagard or Gamunex infusions, suggesting that these immunoglobulin preparations contain COVID-19 antibodies. We are still in the process of analyzing our data to see if diagnosis, IgG preparations, date of testing, B cell numbers, and drugs play a role in producing nucleocapsid antibodies and high spike antibody titers.Copyright © 2023 Elsevier Inc.

Development of warm autoimmune hemolytic anemia after initiation of Ruxolitinib in a patient with STAT1 gain-of-function mutation

Introduction: STAT1 gain-of-function (GOF) disease is associated with chronic mucocutaneous candidiasis (CMC) and a broad spectrum of infectious, inflammatory, and vascular manifestations. The Janus Kinase inhibitor ruxolitinib has been used successfully for CMC and autoimmune phenomena. We describe a case of warm autoimmune hemolytic anemia (WAIHA) in a patient with STAT1 GOF disease after initiating ruxolitinib. Case report: A 36-year-old man with STAT1 c.850G>A (p.Glu284Lys) mutation presented with CMC as well as recurrent viral and bacterial infections, lymphadenopathy, enteritis, nodular regenerative hyperplasia (NRH) and splenomegaly. Immune workup confirmed a combined immunodeficiency with hypogammaglobulinemia and T-cell lymphopenia. Ruxolitinib was initiated at 5 mg twice daily (due to pre-existing thrombocytopenia) with up titration over 3 months to 20 mg twice daily. He improved with weight gain, increased energy, resolution of chronic anemia, and improved lymphadenopathy and splenomegaly on imaging. Serum CXCL9 only minimally decreased from 4660 pg/ml to 3990 pg/ml. Soon after reaching ruxolitinib 20 mg twice daily, he developed JC viremia, prompting dose reduction to 15 mg BID. Within two weeks, he developed a non-COVID upper respiratory tract infection followed by fatigue, shortness of breath with ambulation, and dark urine. Emergency evaluation revealed warm antibody positive hemolytic anemia with a hemoglobin of 5 g/dL, and worsened thrombocytopenia. He was treated with blood transfusions, pulse steroids, and high-dose IVIG with stabilization but continued hemolysis. Due to the JC viremia, there was concern to give rituximab with increased PML risk. Bone marrow showed trilineage hematopoiesis, a mild increase in megakaryocytes and RBC precursors, and a loss of B-cell progenitors with retention of mature B cells. His B and T lymphocyte numbers had increased since prior to ruxolitinib, with a predominance of Tfh1-cells (58.7% of total Tfh-cells). He was started on sirolimus with a slow taper of prednisone with continued stable hemoglobin and platelets, and resolution of hemolysis after 3 months. Conclusion(s): To our knowledge, this is the first case of a STAT1 GOF patient developing WAIHA while receiving ruxolitinib therapy. Treatment choices were complicated by the risks of PML. Sirolimus combined with ruxolitinib allowed wean of corticosteroid and subsequent resolution of hemolysis.Copyright © 2023 Elsevier Inc.

Cellular and Molecular Atlas of Peripheral Blood Mononuclear Cells from a Pregnant Woman after Recovery from COVID-19

Objective This study aimed to investigate the immune response of a pregnant woman who recovered from the coronavirus disease 2019 (COVID_RS) by using single-cell transcriptomic profiling of peripheral blood mononuclear cells (PBMCs) and to analyze the properties of different immune cell subsets. Methods PBMCs were collected from the COVID_RS patient at 28 weeks of gestation, before a cesarean section. The PBMCs were then analyzed using single-cell RNA sequencing. The transcriptional profiles of myeloid, T, and natural killer (NK) cell subsets were systematically analyzed and compared with those of healthy pregnant controls from a published single-cell RNA sequencing data set. Results We identified major cell types such as T cells, B cells, NK cells, and myeloid cells in the PBMCs of our COVID_RS patient. The increase of myeloid and B cells and decrease of T cells and NK cells in the PBMCs in this patient were quite distinct compared with that in the control subjects. After reclustering and Augur analysis, we found that CD16 monocytes and mucosal-Associated invariant T (MAIT) cells were mostly affected within different myeloid, T, and NK cell subtypes in our COVID_RS patient. The proportion of CD16 monocytes in the total myeloid population was increased, and the frequency of MAIT cells in the total T and NK cells was significantly decreased in the COVID-RS patient. We also observed significant enrichment of gene sets related to antigen processing and presentation, T-cell activation, T-cell differentiation, and tumor necrosis factor superfamily cytokine production in CD16 monocytes, and enrichment of gene sets related to antigen processing and presentation, response to type II interferon, and response to virus in MAIT cells. Conclusion Our study provides a single-cell resolution atlas of the immune gene expression patterns in PBMCs from a COVID_RS patient. Our findings suggest that CD16-positive monocytes and MAIT cells likely play crucial roles in the maternal immune response against severe acute respiratory syndrome coronavirus 2 infection. These results contribute to a better understanding of the maternal immune response to severe acute respiratory syndrome coronavirus 2 infection and may have implications for the development of effective treatments and preventive strategies for the coronavirus disease 2019 in pregnant women.Copyright © Wolters Kluwer Health, Inc. All rights reserved.

EXPERIENCE WITH TIXAGEVIMAB AND CILGAVIMAB (EVUSHELD) IN 86 RHEUMATIC PATIENTS UNDERGOING ANTI-B CELL THERAPY WITH RITUXIMAB.

The problem of prevention of coronavirus disease 2019 (COVID-19) in patients with immune-mediated inflammatory rheumatic diseases (IMRD) remains highly relevant. The presence of IRD is associated with a high risk of disease and severe course of COVID-19 during immunosuppressive treatment, primarily anti-B cell therapy with rituximab (RTX), and a low level of post-vaccination response in such patients. A new strategy for the prevention and treatment of COVID-19 are virus-neutralizing monoclonal antibodies to coronavirus;currently, combined long-acting monoclonal antibodies tixagevimab and cilgavimab (Evusheld) are registered for prevention in the world and the Russian Federation. . Tixagevimab and cilgavimab (TC) show neutralizing activity against SARS-CoV-2, including the Omicron strain, primarily its variants BA.4, BA.5, BA.2.75 ("Centaur"). Objective - to evaluate the efficacy and safety of TC for pre-exposure prophylaxis of COVID-19 in rheumatic patients receiving RTX, based on a prospective observational study. Materials and methods. The main group included 86 patients with various IMRD receiving RTX: 50 of them had ANCA-associated systemic vasculitis (AAV), 15 - rheumatoid arthritis, 9 - Sjogren's syndrome (SS), 4 - IgG4-related disease, 3 - systemic lupus erythematosus (SLE), 3 - dermatomyositis (DM), 2 - systemic scleroderma (SSD). Median age was 59 (19-82) years;male: female ratio - 1:1,8. From March 26 to August 30 2022, patients received a single intramuscular injection of TC in a total dose of 300 mg, mainly after RTX (in 52% of cases, in 28% on the next day after RTX). The control group included 42 patients with AAV (median age - 45 (35-71) years;male: female ratio - 1:1), also treated with RTX, who did not receive pre-exposure prophylaxis of TC. The duration of observation was 7 months, until November 1 2022. At this time, 98% of confirmed cases of coronavirus in the Russian Federation were Omicron. A telephone and/or online survey of patient has been conducted to detect cases of COVID-19 and adverse reactions. Results. In the TC group, confirmed coronavirus infection have been detected in 17 (20%) patients (AAV - 10, SS - 3, SSD - 2, SLE - 1, DM - 1), with fever in 7 (8%), only in one case hospitalization was required (lung damage was not detected in computed tomography), in two cases, according to CT mild lung damage (CT 1-2), there were no deaths. Good TC's tolerability was noted, signs not associated with COVID-19 or progression of IMRD after administration of TC were observed in 8 (9%) patients (GPA - 3 MPA - 1, RA - 2, SLE - 1, IgG4-related disease - 1), adverse reactions definitely associated with the use of TC were not found. The most serious event not associated with coronavirus infection was the progression of polyneuropathy in a patient with RA. In the control group, 3 (7%) patients were diagnosed with COVID-19, one with severe lung injury (CT 3, pulmonary embolism) and death. Conclusions. The data of clinical studies and our own clinical experience evidence the effectiveness of the use of a combination of long-acting monoclonal antibodies TC (Evusheld), registered for indications for pre-exposure prophylaxis and treatment of COVID-19. Patients with IMRD treated with RTX have a favorable safety profile of TC. The introduction of virus-neutralizing monoclonal antibodies, a new drug class for the prevention and treatment of infectious diseases, opens significant prospects for improving the prognosis of patients with IRD.Copyright © 2023 Ima-Press Publishing House. All rights reserved.

COVID-19 IN A PATIENT WITH GRANULOMATOSIS WITH POLYANGIITIS: MANAGEMENT TACTICS

Patients with ANCA-associated vasculitis (AAV) cause extreme alertness during the coronavirus disease 2019 (COVID-19) pandemic, associated with many factors: the initial damage to the respiratory system (upper respiratory tract, lungs) and kidneys, immunosuppressive treatments, difficult prognosis of COVID-19 with the risk of AAV exacerbation. We present a clinical case of a moderate COVID-19 in a patient with granulomatosis with polyangiitis, who received anti-B cell therapy with rituximab (RTX) for a long time. Coronavirus pneumonia developed one year after RTX, while B-lymphocyte depletion persisted. In order to achieve an adequate antiviral immune response and prevent hyperinflammation, treatment was carried out with antiviral drugs, anticoagulants, convalescent plasma, human normal immunoglobulin, and interleukin-6 antagonist tocilizumab. Possible predictors of severe COVID-19 in patients with AAV are discussed.Copyright © 2023 Ima-Press Publishing House. All rights reserved.

Lymphocyte Populations and Autoantibodies, in a Cohort of Patients with Rheumatoid Arthritis: A Long-Term Study of Covid-19 Cases and Non-Covid-19 Controls

Objectives: To assess the immunological [Lymphocyte populations (LP) and Autoantibodies (Ab)] and clinical profile of rheumatoid arthritis (RA) patients who suffered from COVID-19 compared with non-COVID-19 RA patients. Method(s): A nested case-control study of RA patients treated under a strict follow-up model. RA patients and confirmed COVID-19 infection (last 24 months) and RA patients without the infection were included. Subgroups of cases: Long COVID (LC): symptoms after infection for >=4 weeks;Post COVID syndrome (PCS): symptoms for >=12 weeks;and patients with symptoms alpha4 weeks. Sociodemographic, clinical, and paraclinical variables of RA and COVID-19 infection (in cases) were captured. Antinuclear antibodies (ANA), anticardiolipin antibodies, lymphocyte populations (BD FACSDuetTM-BDFACSLyricTMmultiparameter flow cytometry) T cells, B cells, and NK were evaluated. Univariate and bivariate analyzes (STATA 17) were done. Result(s): 300 patients were included (148 cases/152 controls;87.3% women). Median age 59 years (IQR 11). 71.86% were in low disease activity. There were no significant differences in sociodemographic and clinical characteristics between cases and controls. Cases had a time since infection of 18.5 months (IQR 7). Of the total cases, 69%presented LC and 63%PCS.No significant differences were found between cases and controls in the lymphocyte population nor in the antibodies evaluated. There were no differences in the immune profile when comparing patients with LC and PCS with those with symptoms alpha4 weeks after COVID-19 infection. Conclusion(s): No differences were found in the behavior of the immunological profile (independent of symptoms of LC and PCS) in RA patients under strict follow up, evaluated long-term after infection with those who did not have COVID-19. This suggest that patients returned to their baseline homeostatic state, something that has not yet been reported up to now. These results should be replicated in populations with different RA characteristics.

Analysis of Antibody Response to Sars-Cov-2 Vaccination and Natural Infection in a Tertiary Centre Cohort of Lupus Nephritis Patients

Background/Aims The immune response to SARS-CoV-2 is known to be reduced in the immunocompromised. However, extent to which immunity is affected by immunosuppression in specific disease cohorts remains poorly characterised. Furthermore, implications of the ongoing vaccination booster programme require further study. Individuals with lupus nephritis (LN) require prolonged high-dose immunosuppression in order to maintain disease control, rendering them important to study in this context. We evaluated SARS-CoV-2 nucleocapsid and spike antibody response in this cohort during the Spring/Summer 2022 booster vaccine campaign. Nucleocapsid antibody indicates previous infection whilst spike antibody indicates previous infection and/or vaccination response. Titre of spike antibody to prevent infection is not known, but presence of antibodies is likely to protect against severe disease. Methods SARS-CoV-2 spike and nucleocapsid antibody were measured in adult patients with LN attending a tertiary centre rheumatology clinic. Data was collected retrospectively on disease, immunosuppression, vaccine status and history of natural exposure. Results 35 cases of LN were investigated, of which LN III, IV and V were predominant biopsy diagnoses. Regarding immunosuppressants, the Eurolupus Cyclophosphamide protocol had been used in the majority of patients to achieve initial control, with 3/35 patients still receiving pulsed courses at data collection. 18/35 were on Mycophenolate Mofetil;a further 13/35 had previously received this. 31/35 took at least 5mg Prednisolone daily;25/35 took Hydroxychloroquine;7/35 took Azathioprine;7/35 had previously been on Methotrexate, 3/35 took Tacrolimus;1/35 took Ciclosporin. Regarding B-cell depleting monoclonal antibody therapy, 13/35 had received Rituximab and 8/35 were receiving Belimumab. Antibody levels were measured between 4 weeks and 13 months after last dose of vaccination;mean duration was 6 months. 11/35 had confirmed COVID-19 infection;a further 8/35 reported a possible history. Of the 35, 32 (91%) had mounted detectable SARS-CoV-2 spike antibody above the bottom 10% of assay detection, indicating some immunity to vaccination or natural exposure. 20 (57%) had detectable nucleocapsid antibody, suggesting natural infection with antibody response. Only 2 (6%) had not mounted any antibody response. Of note, neither were fully vaccinated: one had 1 vaccination with blood test 8 months subsequent;one had 2 vaccinations with blood test 7 months subsequent. The latter was also notably on haemodialysis. All who received 3+ vaccinations had detectable spike antibody responses, as well as 75% of those who had received 2 vaccinations. Conclusion Our study is the first analysis, to our knowledge, of SARS-CoV-2 antibody response in a LN cohort. Whilst neutralising capacity and level of antibody providing protection remains under research, these findings provide at least some reassurance that individuals with LN on immunosuppression are capable of mounting an immune response against SARS-CoV-2. Further work is required to establish extent and duration of protection with serial vaccinations in this cohort.

A Descriptive, Retrospective Analysis of Covid-19 Antibody Therapy and Its Effects on Morbidity and Mortality in Patients Receiving B-Lymphocyte Depleting Therapies

Intro: Patients receiving B-cell depleting or inhibiting therapies (BCDT), such as anti-CD20 monoclonal antibodies (CD20-MAB), are at risk for severe COVID-19. BCDT decreases production of neutralizing antibodies, causing delayed viral clearance and prolonged viral shedding. Passive antibody therapy (PAT), including COVID-19 convalescent plasma (CCP) and monoclonal antibodies (MAB), is hypothesized to be an effective Findings: * At the time of treatment, all patients (19/19) receiving CCP were hospitalized compared with10/53 patients treated with MAB. 2/10(20%) hospitalized patients treated with MAB died, compared with 3/19(15%) treated with CCP. **5/43 patients treated outpatient with MAB were hospitalized for COVID following CCP/MAB treatment with no COVID related deaths. Conclusion(s): Our data suggest that patients with COVID-19 who received BCDT within the last year may have improved outcomes after treatment with MAB or CCP. Elderly patients with >3 comorbidities and underlying hematological malignancy who contracted COVID-19 within 30 days of last BCDT had increased morbidity and mortality. To improve clinical outcomes, passive antibody therapy should be administered prior to the development of severe disease requiring hospitalization. Further prospective studies and comparisons to COVID-19 patients that did not receive MAB or CCP are needed to help confirm this association.Copyright © 2023

Immune Responses to Mrna Vaccines against Sars-Cov2 in Patients with Immune-Mediated Inflammatory Rheumatic Diseases

Background/Aims Patients with immune-mediated rheumatic diseases (IMRD) are commonly treated with immunosuppressors and are prone to infections. Recently introduced mRNA SARS-Cov2 vaccines have demonstrated extraordinary efficacy across all ages. Immunosuppressed patients were excluded from phase III trials with SARS-We aim to fully characterize B and T cell immune responses elicited by mRNA SARS-Cov2 vaccines in patients with rheumatic diseases under immunotherapies, and to identify which drugs reduce vaccine's immunogenicity. Methods Humoral, CD4 and CD8 immune responses were investigated in 147 SARS-Cov2-naive patients with selected rheumatic diseases under immunosuppression after a two-dose regimen of SARS-Cov2 mRNA vaccine. Responses were compared with age, gender, and diseasematched IMRD patients not receiving immunosuppressors and with healthy controls Results IMRD patients showed decreased seroconversion rates (63% vs 100%, p=0.04) and cellular immune responses (59% vs 100%, p=0.007). Patients on methotrexate achieved seroconversion in 62% of cases and cellular responses in 80% of cases. Abatacept deeply affected humoral and cellular responses. Rituximab (31% responders) and belimumab (50% responders) showed severely impaired humoral responses but cellular responses were often preserved. Antibody titers were reduced with mycophenolate and azathioprine but preserved with leflunomide. Conclusion IMRD patients exhibit impaired SARS-CoV-2 vaccine-immunogenicity, variably reduced with immunosuppressors. Among commonly used therapies, abatacept and B-cell depleting therapies show the most deleterious effects, while anticytokines preserved immunogenicity. The effects of cumulative methotrexate and glucocorticoid doses on immunogenicity should be considered. Humoral and cellular responses are weakly correlated, but CD4 and CD8 tightly correlate. Seroconversion alone might not reflect the vaccine's immunogenicity.

Adaptive Immunity Dysregulation Is Associated to the Development of Long Covid

Background: The pathogenetic mechanisms behind the development of long- COVID (LC) are largely unknown. Because both plasma SARS-CoV-2 RNAemia and dysregulated immunity have been correlated with COVID-19 severity, we evaluated whether they are associated with LC. Method(s): We consecutively enrolled unvaccinated hospitalized COVID-19 patients during acute-COVID-19 (T0) in March-October 2020 who either developed LC at a follow-up visit 2-3 months from virologic clearance (T1) or did not. LC was defined as persistence >=2 months after recovery of >=1 symptom: anosmia, dysgeusia, fever, gastrointestinal symptoms, dyspnoea, fatigue, musculoskeletal pain, muscle weakness, brain fog. We measured: SARS-CoV-2 RNAemia (RT-qPCR, log10(copies/mL)), magnitude (ELISA, AUC) and functionality (pseudovirus neutralization, ID50;Fc-mediated functions, %ADCC) of SARS-CoV-2-specific antibodies, SARS-CoV-2-specific B and CD4-T-cells (Immunophenotype, AIM and ICS assays). Result(s): We enrolled 48 COVID-19 individuals, 38/48 (79.2%) developed LC (LC+) and 10 did not (LC-). LC+ and LC- had similar co-morbidities and symptoms in the acute phase (Fig.1A), and the majority showed a radiologically documented SARS-CoV-2 pneumonia. The SARS-CoV-2 RNAemia did not differ between groups at both time points. The levels of RBD-specific Abs, as well as their functionality, appeared to increase over time in the LC- group but not in the LC+ (Fig.1B-D). Similarly, a trend towards increased RBD-specific B-cells was observed over time in the LC- group but not in LC+ (Fig.1E). B-cell immunophenotyping showed a significant increase over time of classical memory B cells (MBCs) at the expenses of activated MBCs (Fig.1F-G) as well as an IgA class-switching in the LC- group compared to LC+ (Fig.1H-I). Furthermore, LC+ showed a faster decline of SARS-CoV-2-specific (CD69+CD137+) CD4- TEMRA and CD4-TEM (Fig.1L-M). Finally, IFN-gamma-producing TREG of LC- individuals increased over time (Fig.1N). Conclusion(s): Acutely ill, hospitalized COVID-19 patients developing LC feature a dysregulated SARS-CoV-2-specific humoral as well as B- and T-cell response, in both magnitude and functionality, suggesting a link between dysregulated SARS-CoV-2-specific adaptive immunity and LC development. The fine understanding of the factors contributing to such dysregulation in LC patients is strongly needed, that might further inform targeted therapeutic interventions. (Figure Presented).

Development of a New Epitope Immunogenic Structure Based on the Coronavirus Membrane Glycoprotein M Using Immunoinformatics Tools

Backgrounds: Although conventional therapies have played an essential role in the treatment of many diseases, emerging diseases require new treatment methods with less complications. Therefore, it is important to develop an effective vaccine for infections caused by the coronavirus to prevent mortality and create immunity the community. Material(s) and Method(s): In this research bioinformatics tools were used to design a vaccine against the M membrane protein of SARS-CoV-2. A total of 27 epitopes confined to B cells and MHC I and II alleles were structurally constructed in M protein for immune stimulation and antibody recognition which were used in the construction of a chimeric peptide vaccine. Finding(s): The vaccine was predicted to be a stable, antigenic, and non-allergenic compound. TRL5/vaccine complex analysis and docking simulation indicated a sufficiently stable binding with appropriated receptor activation. The immune response simulation following hypothetical immunization indicated the potential of this vaccine to stimulate the production of active and memory B cells, CD8 + T and, CD4 + T cells, and effective immunological responses induced by Th2 and Th1. Conclusion(s): The analysis of in-silico processes showed that the vaccine structure induced high antigenicity and good cellular immunity in the host body and stimulates various immune receptors such as TLR5, MHC I, and MHC II. Vaccine function was also associated with an increase in IgM and IgG antibodies and a set of Th1 and Th2 cytokines. But the final confirmation of the effectiveness of the designed vaccine requires clinical processes.Copyright © 2022, TMU Press.

Memory B Cell Responses to New Virus Variants: Relevance to the Concept of Original A

In this presentation, Dr Marion Pepper will discuss Memory B cell responses to COVID-1.