IFIH1 loss-of-function predisposes to inflammatory and SARS-CoV-2-related infectious diseases (preprint)

The IFIH1 gene, encoding melanoma differentiation-associated protein 5 (MDA5), is an indispensable innate immune regulator involved in the early detection of viral infections. Previous studies described MDA5 dysregulation linking it to weakened immunological responses, and increased susceptibility to microbial infections and autoimmune disorders. Monoallelic gain-of-function of the IFIH1 gene has been associated with multisystem disorders, namely Aicardi-Goutieres and Singleton-Merten syndromes, while biallelic loss of this gene causes immunodeficiency. In this study, nine patients suffering from different cases of recurrent infections, inflammatory diseases, severe COVID-19, or multisystem inflammatory syndrome in children (MIS-C) were identified with putative loss-of-function IFIH1 variants by whole exome sequencing. All patients revealed signs of lymphopenia and an increase in inflammatory markers, including CRP, amyloid A, ferritin, and IL-6. One patient with a pathogenic homozygous variant c.2807+1G>A was the most severe case showing immunodeficiency and glomerulonephritis. The c.1641+1G>C variant was identified in the heterozygous state in patients suffering from periodic fever, COVID-19, or MIS-C, while the c.2016delA variant was identified in two patients with inflammatory bowel disease or MIS-C. Expression analysis showed that PBMCs of one patient with a c.2016delA variant had a significant decrease in ISG15, IFNA and IFNG transcript levels, compared to normal PBMCs, upon stimulation with poly(I:C), suggesting that MDA5 receptor truncation disrupts the immune response. Our findings accentuate the implication of rare monogenic IFIH1 loss-of-function variants in altering the immune response, and severely predisposing patients to inflammatory and infectious diseases, including SARS-CoV-2 related disorders.

The Role of the Immune System on the Cardiac Complications Observed in SARS-CoV-2

Abstract An acute respiratory syndrome caused by SARS-CoV2 was declared a pandemic by the World Health Organization. Current data in the world and in Brazil show that approximately 40% of patients who died have some type of cardiac comorbidity. There are also robust reports showing an increase in IL-6 / IL-1B / TNF-alpha and the presence of lymphopenia in patients with COVID-19. Our team and others have shown that increased cytokines are the link between arrhythmias/Left ventricular dysfunction and the immune system in different diseases. In addition, it has been well demonstrated that lymphopenia can not only be a good marker, but also a factor that causes heart failure. Thus, the present review focused on the role of the immune system upon the cardiac alterations observed in the SARS-CoV2 infection. Additionally, it was well described that SARS-CoV-2 is able to infect cardiac cells. Therefore, here it will be reviewed in deep.

Pathological Effects of SARS-CoV-19 Associated With Hematological Abnormalities (preprint)

The SARS coronavirus 2 (SARS-CoV-2) is the causative agent of the 2019 coronavirus disease (COVID-19) pandemic that has executed 6.9 million people and infected over 765 million. It’s become a major worldwide health alarm and is also known to cause abnormalities in various systems, including the hematologic system. COVID-19 infection primarily affects the lower res-piratory tract and can lead to a cascade of events, including a cytokine storm, intravascular thrombosis, and subsequent complications such as arterial and venous thromboses. COVID-19 can cause thrombocytopenia, lymphopenia, and neutrophilia, which are associated with worse out-comes. Prophylactic anticoagulation is essential to prevent complication and death rate associated with the virus's effect on the coagulation system. It is crucial to recognize these complications early and promptly start therapeutic anticoagulation to improve patient outcomes. While rare, COVID-19-induced disseminated intravascular coagulation exhibits some similarities to DIC induced by sepsis. LDH, D-dimer, ferritin, and CRP biomarker are often increase in serious COVID-19 cases and poor prognosis. Understanding the pathophysiology of the disease and identifying risk factors for adverse outcomes is critical for effective management of COVID-19.

The shed P2X7 receptor is an index of adverse clinical outcome in COVID-19 patients.

Introduction: The pathophysiology of the Corona Virus Disease 2019 (COVID-19) is incompletely known. A robust inflammatory response caused by viral replication is a main cause of the acute lung and multiorgan injury observed in critical patients. Inflammasomes are likely players in COVID-19 pathogenesis. The P2X7 receptor (P2X7R), a plasma membrane ATP-gated ion channel, is a main activator of the NLRP3 inflammasome, of the ensuing release of inflammatory cytokines and of cell death by pyroptosis. The P2X7R has been implicated in COVID-19-dependent hyperinflammation and in the associated multiorgan damage. Shed P2X7R (sP2X7R) and shed NLRP3 (sNLRP3) have been detected in plasma and other body fluids, especially during infection and inflammation. Methods: Blood samples from 96 patients with confirmed SARS-CoV-2 infection with various degrees of disease severity were tested at the time of diagnosis at hospital admission. Standard haematological parameters and IL-6, IL-10, IL-1ß, sP2X7R and sNLRP3 levels were measured, compared to reference values, statistically validated, and correlated to clinical outcome. Results: Most COVID-19 patients included in this study had lymphopenia, eosinopenia, neutrophilia, increased inflammatory and coagulation indexes, and augmented sNLRP3, IL-6 and IL-10 levels. Blood concentration of sP2X7R was also increased, and significantly positively correlated with lymphopenia, procalcitonin (PCT), IL-10, and alanine transaminase (ALT). Patients with increased sP2X7R levels at diagnosis also showed fever and respiratory symptoms, were more often transferred to Pneumology division, required mechanical ventilation, and had a higher likelihood to die during hospitalization. Conclusion: Blood sP2X7R was elevated in the early phases of COVID-19 and predicted an adverse clinical outcome. It is suggested that sP2X7R might be a useful marker of disease progression.

Reappraisal of Idiopathic CD4 Lymphocytopenia at 30 Years.

BACKGROUND: Idiopathic CD4 lymphocytopenia (ICL) is a clinical syndrome that is defined by CD4 lymphopenia of less than 300 cells per cubic millimeter in the absence of any primary or acquired cause of immunodeficiency. Some 30 years after its original identification, ICL has remained a disease of obscure cause, with limited evidence with respect to its prognosis or management, despite diagnostic and therapeutic innovations. METHODS: We evaluated the clinical, genetic, immunologic, and prognostic characteristics of 108 patients who were enrolled during an 11-year period. We performed whole-exome and targeted gene sequencing to identify genetic causes of lymphopenia. We also performed longitudinal linear mixed-model analyses of T-cell count trajectories and evaluated predictors of clinical events, the response to immunization against coronavirus disease 2019 (Covid-19), and mortality. RESULTS: After the exclusion of patients with genetic and acquired causes of CD4 lymphopenia, the study population included 91 patients with ICL during 374 person-years of follow-up. The median CD4+ T-cell count among the patients was 80 cells per cubic millimeter. The most prevalent opportunistic infections were diseases related to human papillomavirus (in 29%), cryptococcosis (in 24%), molluscum contagiosum (in 9%), and nontuberculous mycobacterial diseases (in 5%). A reduced CD4 count (<100 cells per cubic millimeter), as compared with a CD4 count of 101 to 300 cells, was associated with a higher risk of opportunistic infection (odds ratio, 5.3; 95% confidence interval [CI], 2.8 to 10.7) and invasive cancer (odds ratio, 2.1; 95% CI, 1.1 to 4.3) and a lower risk of autoimmunity (odds ratio, 0.5; 95% CI, 0.2 to 0.9). The risk of death was similar to that in the age- and sex-adjusted general population, but the prevalence of cancer was higher. CONCLUSIONS: Among the study patients, ICL continued to be associated with increased susceptibility to viral, encapsulated fungal, and mycobacterial diseases, as well as with a reduced response to novel antigens and an increased risk of cancer. (Funded by the National Institute of Allergy and Infectious Diseases and the National Cancer Institute; ClinicalTrials.gov number, NCT00867269.).

Kinetics of cellular and humoral immunogenicity and effectiveness of SARS-CoV-2 booster vaccination in hematologic neoplasms.

Data on the effect of booster SARS-CoV-2 vaccination are mainly focused on humoral immunogenicity, while the kinetics of vaccine-induced cellular response and its correlation with effectiveness in hematologic patients are less explored. Our aim was to evaluate the longitudinal cellular and humoral immunogenicity induced by two and three doses of the mRNA-1273 SARS-CoV-2 vaccine in 270 patients with hematologic malignancies, and its relationship with the severity of breakthrough SARS-CoV-2 infection. Results indicate that at 23 weeks after the second dose, the seroconversion rate declined from 68.5% to 59.3%, with a reduction in median anti-S titers from 1577 to 456 BAU/mL, mainly in patients over 65 years of age or chronic lymphocytic leukemia (CLL) patients undergoing active therapy. Cellular immunogenicity, however, remained positive in 84.4% of cases. A third vaccine dose seroconverted 42.7% (41/96) and triggered cellular response in 36.7% (11/30) of previously negative patients. Notably, only 7.2% (15/209) of patients failed to develop both humoral and cellular response. Active therapy, anti-CD20 antibodies, lymphopenia, hypogammaglobulinemia, and low CD19+ cell count were associated with poor humoral response, while active disease, GvHD immunosuppressive therapy, lymphopenia, and low CD3+ , CD4+ , CD56+ cell count determined an impaired cellular response. After 13.8 months of follow-up, the incidence of SARS-CoV-2 infection was 24.8% (67/270), including 6 (9%) severe/critical cases associated with a weaker cellular (median interferon gamma (IFN-γ) 0.19 vs. 0.35 IU/mL) and humoral response (median anti-S titer <4.81 vs. 788 BAU/mL) than asymptomatic/mild cases. In conclusion, SARS-CoV-2 booster vaccination improves humoral response and COVID-19 severity is associated with impaired vaccine-induced immunogenicity.

Predictors of mortality in hemodialysis patients with COVID-19: A single-center experience.

INTRODUCTION: The COVID-19 pandemic has disproportionately affected patients with preexisting comorbidities, particularly dialysis patients. The aim of this study was to determine predictors of mortality in this population. METHODOLOGY: We conducted an observational, retrospective, cohort study collecting data from pre and post-vaccine from the electronic medical records of a single dialysis center at Hygeia International Hospital Tirana, Albania. RESULTS: Of 170 dialysis patients, 52 were diagnosed with COVID-19. The prevalence of COVID-19 infection in our study was 30.5%. The mean age was 61.5 ± 12.3 years and 65.4% were men. The mortality rate in our cohort was 19.2%. Mortality rates were higher in patients with diabetic nephropathy (p < 0.04) and peripheral vascular disease (p < 0.01). Elevated C- reactive protein (CRP) (p < 0.018), high red blood cell distribution width (RDW) (p < 0.03), and low lymphocyte and eosinophil counts, were found to be risk factors for severe COVID-19 disease. ROC analysis identified lymphopenia and eosinopenia as the strongest predictors of mortality. After the vaccine administration, the mortality rate in the vaccinated population was 8%, in contrast to the 66.7% mortality rate that was found in the unvaccinated group (p < 0.001). CONCLUSIONS: Our study revealed that risk factors for the development of severe COVID-19 infection were RDW, low lymphocyte and eosinophil counts, elevated levels of CRP. Lymphopenia and eosinopenia were determined as the most important predictors of mortality, in our cohort. Mortality was notably lower among vaccinated patients.

Viral infection of hematopoietic stem cells (preprint)

Hematopoietic stem cells (HSCs) are critical for maintaining healthy blood and immune cell populations. They’re also valuable resources and targets for medical treatments, such as HSC transplantation and gene therapy. However, these blood cell precursors are susceptible to viral infection, which can cause blood disorders and limit the efficacy of HSC-based therapies. In fact, viral infection is a leading cause of complications and death among HSC transplant recipients. For example, latent cytomegalovirus can become reactivated after transplantation leading to immunosuppression, pneumonia, encephalitis, and graft failure. HSC transplantation also reduces the numbers of T cells that are specifically cytotoxic toward the mononucleosis- inducing Epstein–Barr virus. Furthermore, recipients of HSC transplants are more susceptible to infection by SARS-CoV-2, the cause of the COVID-19 pandemic. SARS-CoV-2, in turn, can induce numerous blood abnormalities, such as thrombocytopenia, lymphocytopenia, anemia, hypercoagulability, and systemic thrombosis in part because HSCs express SARS-CoV-2 receptors. More research is needed to determine the best ways to prevent viral infection of these essential cells in both endogenous and transplantation contexts, in order to reduce serious blood disorders and related mortality in the clinic.

The unreversible reduced but persistent activated NK and CD8+ T cells in severe/critical COVID-19 during omicron pandemic in China.

As a hallmark of COVID-19 progression, lymphopenia alongside its subtle immune disturbance has been widely reported, but yet to be thoroughly elucidated. Aiming at exploring clinical immune biomarkers with accessibility in the current and acute omicron epidemic abrupted in China post-control era, we design a real-world prospective observation cohort in Peking Union Medical College Hospital to describe immunological, haematological profiles inducing lymphocyte subsets related to SARS-CoV-2 infection. In this COVID-19 cohort, we enrolled 17 mild/moderate (M/M), 24 severe (S) and 25 critical (C) patients. The dynamics of lymphocytes of COVID-19 demonstrated that the sharp decline of NK, CD8+, and CD4+ T cell counts was the main contributor to lymphopenia in the S/C group, compared to the M/M group. Expressions of activation marker CD38 and proliferation marker Ki-67 both in CD8+ T and NK cells were significantly higher in all COVID-19 patients than that in healthy donors, independent of disease severity. The subsequent analysis showed in contrast to the M/M group, NK and CD8+ T cell counts remained low-level after therapy in the S/C group. CD38 and Ki-67 expressions in NK and CD8+ T cells still stay at a high level, despite active treatment. Targeting relatively elderly patients with SARS-CoV-2 infection, severe COVID-19 features the unreversible reduction of NK and CD8+ T cells with persistent activation and proliferation, which assist clinicians in early recognizing and saving severe or critical COVID-19 patients. Given that immunophenotype, the new immunotherapy improving NK and CD8+ T lymphocyte antiviral efficiency should be considered.

The Role of Lymphocyte Subsets, PD-1, and FAS (CD95) in COVID-19 Cancer Patients.

Lymphocytes are the main orchestrators that regulate the immune response in SARS-COV-2 infection. The exhaustion of T lymphocytes is a contributing factor to lymphopenia, which is responsible for the COVID-19 adverse outcome. However, it is still not demonstrated on a large scale, including cancer patients. Peripheral blood samples were obtained from 83 SARS-CoV2 infected cancer patients, and 29 COVID-19 infected noncancer patients compared to 28 age-matched healthy controls. Lymphocyte subsets were assessed for CD3, CD4, CD8, CD56, PD-1, and CD95 using flow cytometry. The data were correlated to the patients' clinical features, COVID-19 severity and outcomes. Lymphopenia, and decreased CD4+ T cells and CD8+ T cells were significantly observed in COVID-19 cancer and noncancer patients compared to the control group (p < 0.001, for all). There was a significantly increased expression of CD95 and PD-1 on the NK cells, CD4+ T cells, and CD8+ T cells in COVID-19 cancer and noncancer patients in comparison to the control group. The increased expression of CD95 on CD8+ T cells, as well as the increased expression of PD-1 on CD8+ T cells and NK cells are significantly associated with the severity of COVID-19 infection in cancer patients. The increased expression of CD95 and PD-1 on the CD4+ T cells, CD8+ T cells, and NK cells was observed significantly in nonsurviving patients and those who were admitted to the intensive care unit in COVID-19 cancer and noncancer patients. The increased expression of PD-1 and CD95 could be possible prognostic factors for COVID-19 severity and adverse outcomes in COVID-19 cancer and noncancer patients.

Initial Observations of COVID-19 in US Children.

Coronavirus disease (COVID-19) has affected children differently from adults worldwide. Data on the clinical presentation of the infection in children are limited. We present a detailed account of pediatric inpatients infected with severe acute respiratory syndrome coronavirus 2 virus at our institution during widespread local transmission, aiming to understand disease presentation and outcomes. A retrospective chart review was performed of children, ages 0 to 18 years, with a positive polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2 on nasopharyngeal specimens admitted to our hospital over a 4-week period. We present clinical data from 22 patients and highlight the variability of the presentation. In our study, most children presented without respiratory illness or symptoms suggestive of COVID-19; many were identified only because of universal testing. Because children may have variable signs and symptoms of COVID-19 infection, targeted testing may miss some cases.

Comprehensive Immune Profiling Reveals CD56+ Monocytes and CD31+ Endothelial Cells Are Increased in Severe COVID-19 Disease.

Immune response dysregulation plays a key role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogenesis. In this study, we evaluated immune and endothelial blood cell profiles of patients with coronavirus disease 2019 (COVID-19) to determine critical differences between those with mild, moderate, or severe COVID-19 using spectral flow cytometry. We examined a suite of immune phenotypes, including monocytes, T cells, NK cells, B cells, endothelial cells, and neutrophils, alongside surface and intracellular markers of activation. Our results showed progressive lymphopenia and depletion of T cell subsets (CD3+, CD4+, and CD8+) in patients with severe disease and a significant increase in the CD56+CD14+Ki67+IFN-γ+ monocyte population in patients with moderate and severe COVID-19 that has not been previously described. Enhanced circulating endothelial cells (CD45-CD31+CD34+CD146+), circulating endothelial progenitors (CD45-CD31+CD34+/-CD146-), and neutrophils (CD11b+CD66b+) were coevaluated for COVID-19 severity. Spearman correlation analysis demonstrated the synergism among age, obesity, and hypertension with upregulated CD56+ monocytes, endothelial cells, and decreased T cells that lead to severe outcomes of SARS-CoV-2 infection. Circulating monocytes and endothelial cells may represent important cellular markers for monitoring postacute sequelae and impacts of SARS-CoV-2 infection during convalescence and for their role in immune host defense in high-risk adults after vaccination.

[Salmonella Bacteremia Accompanying COVID-19: The First Salmonella Co-Infection in the World Unrelated to Pakistan]. / COVID-19'a Eslik Eden Salmonella Bakteremisi: Pakistan ile Iliskisiz Dünyadaki Ilk Salmonella Ko-Enfeksiyonu.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection emerged in China at the end of 2019 and caused coronavirus disease 2019 (COVID-19). The lymphopenia seen in COVID-19 increases the incidence of susceptibility to other microorganisms and may cause co-infections. As the signs and symptoms of the diseases overlap with other infectious diseases and due to the intensity in health services, the diagnosis of co-infections becomes difficult and the treatment may be delayed. Therefore, infections accompanying COVID-19 cause an increase in morbidity and mortality.The isolation and quarantine measures taken during the COVID-19 process have reduced the number of infections transmitted from person to person. However, there was no significant decrease in diseases transmitted by food, such as salmonellosis. During the pandemic, salmonellosis continued to be a problem, especially in endemic areas such as Pakistan, and an increase in Salmonella infections associated with backyard poultry has been reported in countries such as the United States. A co-infection of COVID-19 and enteric fever associated with travel to Pakistan was reported for the first time in the literature in February 2021. In this case report, the first co-infection of COVID-19 and Salmonella in our country was presented. A 56-yearold male patient with no known systemic disease was admitted to the hospital with fever, shortness of breath, weakness and myalgia lasting for three days. SARS-CoV-2 polymerase chain reaction test was positive. The patient has been hospitalized and favipiravir, moxifloxacin, and methylprednisolone were started. Blood cultures were taken from the patient whose clinical picture worsened and fever continued despite of the medical treatment. Salmonella enterica spp. enterica was isolated and ceftriaxone treatment was started. The patient's anamnesis was deepened, but no diarrhea, abdominal pain, suspicious food consumption, travel history were determined. From the second day of the ceftriaxone treatment, the patient's fever decreased and no growth was detected in the control blood cultures. Ceftriaxone treatment was completed in 14 days and the patient was discharged on the 28th day. Approximately 87-95% of Salmonella strains isolated in our country are S.enterica spp. enterica, and S.enterica spp. enterica was also isolated in our case. Salmonella infections most commonly present as gastroenteritis, but the risk of bacteremia increases in case of immunosuppression. Although there was no additional disease in our case, it was considered that the infection in the form of bacteremia occurred due to an immunosuppression caused by COVID-19. In this context; drawing blood cultures of patients hospitalized with the diagnosis of COVID-19 is very important in terms of detecting co-infections and superinfections, and administering appropriate antibiotic therapy at appropriate treatment times. Presentation of first case of Salmonella bacteremia and simultaneous COVID-19 infection in our country was the strong side of our report. In addition, our case is also important as being the first SARS-CoV-2 and Salmonella co-infection unrelated to Pakistan in the literature. The limitation of our case was that S.enterica spp. enterica detected in the blood culture could not be subtyped and the stool culture could not be examined. However, this does not constitute a diagnostic requirement. In addition, the patient's pre-COVID-19 Salmonella carrier status was also unknown. As a result, patients become vulnerable to other infections due to the lymphopenia seen in COVID-19. Therefore, Salmonella bacteremia can be seen with SARS-CoV-2 infection without a comorbid condition. Drawing blood cultures in hospitalized patients with the diagnosis of COVID-19 is very important in terms of detecting concomitant infections in a short time. In patients whose clinical condition does not improve and fever continues despite of treatment, blood cultures should be taken, especially in the case of an advanced immunosuppresive treatment plan, and it should always be kept in mind that secondary infections and co-infections may occur.

Early administration of remdesivir plus convalescent plasma therapy is effective to treat COVID-19 pneumonia in B-cell depleted patients with hematological malignancies.

Patients with hematological malignancies (HMs) are at a higher risk of developing severe form and protracted course of COVID-19 disease. We investigated whether the combination of viral replication inhibition with remdesivir and administration of anti-SARS-CoV-2 immunoglobulins with convalescent plasma (CP) therapy might be sufficient to treat B-cell-depleted patients with COVID-19. We enrolled 20 consecutive patients with various HMs with profound B-cell lymphopenia and COVID-19 pneumonia between December 2020 and May 2021. All patients demonstrated undetectable baseline anti-SARS-CoV-2 immunoglobulin levels before CP. Each patient received at least a complete course of remdesivir and at least one unit of CP. Previous anti-CD20 therapy resulted in a more prolonged SARS-CoV-2 PCR positivity compared to other causes of B-cell lymphopenia (p = 0.004). Timing of CP therapy showed a significant impact on the clinical outcome. Simultaneous use of remdesivir and CP reduced time period for oxygen weaning after diagnosis (p = 0.017), length of hospital stay (p = 0.007), and PCR positivity (p = 0.012) compared to patients who received remdesivir and CP consecutively. In addition, time from the diagnosis to CP therapy affected the length of oxygen dependency (p < 0.001) and hospital stay (p < 0.0001). In those cases where there were at least 10 days from the diagnosis to plasma administration, oxygen dependency was prolonged vs. patients with shorter interval (p = 0.006). In conclusion, the combination of inhibition of viral replication with passive immunization was proved to be efficient and safe. Our results suggest the clear benefit of early, combined administration of remdesivir and CP to avoid protracted COVID-19 disease among patients with HMs and B-cell lymphopenia.

Effectiveness and safety of switching to teriflunomide in older patients with relapsing multiple sclerosis: A real-world retrospective multicenter analysis.

BACKGROUND: The prevalence of multiple sclerosis (MS) in older people is increasing due to population aging and availability of effective disease-modifying therapies (DMTs). Treating older people with MS is complicated by age-related and MS-related comorbidities, immunologic effects of prior DMTs, and immunosenescence. Teriflunomide is a once-daily oral immunomodulator that has demonstrated efficacy and acceptable safety in clinical trials of adults with relapsing forms of MS (RMS). However, there are limited clinical trial and real-world data regarding teriflunomide use in people with MS aged >55 years. We analyzed real-world data to assess the effectiveness and safety of teriflunomide in older people with RMS who had switched to this agent from other DMTs. METHODS: People with RMS (relapsing remitting and active secondary progressive MS) aged ≥55 years who had switched from other DMTs to teriflunomide (7 mg or 14 mg) for ≥1 year were identified retrospectively by chart review at four sites in the United States. Data were extracted from medical records from 1 year pre-index to 2 years post-index (index defined as the teriflunomide start date). Assessments of effectiveness included annualized relapse rate (ARR), Expanded Disability Status Scale (EDSS) score, and magnetic resonance imaging (MRI) outcomes. Assessments of safety included lymphocyte counts, infections, and malignancies. We examined the effectiveness outcomes and lymphocyte counts within sub-groups defined by age (55-64, ≥65 years), sex, MS type, and prior route of DMT administration (oral, injectable, infusible). RESULTS: In total, 182 patients with RMS aged ≥55 years who switched from other DMTs to teriflunomide were identified (mean [SD] age: 62.5 [5.4] years). Mean ARR decreased from the start of teriflunomide treatment (mean [SD]: 0.43 [0.61]) to year 1 post-index (0.13 [0.65]) and year 2 post-index (0.05 [0.28]). Mean EDSS score remained unchanged from index (mean [SD]: 4.5 [1.8]) to 1 year post-treatment (4.5 [1.8]) and increased slightly at 2 years post-treatment (4.7 [1.7]). MRI scans from index and years 1 and 2 post-index compared with scans from the previous year indicated that most patients had stable or improved MRI outcomes at index (87.7%) and remained stable or improved at years 1 (96.0%) and 2 (93.6%). Lymphopenia decreased at years 1 (21.4%) and 2 post-index (14.8%, compared to index (23.5%). By 1 year post-index, fewer patients had grade 3 or 4 lymphopenia, and at 2 years post-index, there were no patients with grade 3 or 4 lymphopenia. Infection incidence was low (n = 40, 22.0%) and none were related to teriflunomide. The decreases in lymphopenia were driven by decreases among people who switched from a prior oral DMT; there were no notable differences in lymphopenia across the other sub-groups examined. ARR, EDSS score, and MRI outcomes across all sub-groups were similar to the results of the overall population. CONCLUSION: Our multicenter, longitudinal, retrospective study demonstrated that patients with RMS aged 55 or older switching to teriflunomide from other DMTs had significantly improved ARR, stable disability, and stable or improved MRI over up to 2 years' follow up. Safety results were acceptable with fewer patients exhibiting lymphopenia at years 1 and 2 post-index.

Correlation of Expression of MMP-2, ACE2, and TMPRSS2 Genes with Lymphopenia for Mild and Severity of COVID-19.

Some risk causes may be associated with the severity of COVID-19. The central host-pathogen factors might affect infection are human receptor angiotensin-converting enzyme 2 (ACE2), trans-membrane protease serine 2 (TMPRSS2), and SARS-CoV-2 surface spike (S)-protein. The main purpose of this study was to determine the differences in the expression the metalloproteinases-2  (MMP-2), MMP-9, ACE2, and TMPRSS2 genes and their correlation with lymphopenia in the mild and severe types of the COVID-19 patients. Eighty-eight patients, aged 36 to 60 years old with the mild (n=44) and severe (n=44) types of COVID-19 were enrolled. Total RNA was isolated from the peripheral blood mononuclear cells (PBMCs). The changes of MMP-2, MMP-9, ACE2 and TMPRSS2 gene expression in PBMCs from mild and severe COVID-19 patients were examined by the real time-quantitative polymerase chain reaction (RT-qPCR) assay and, compared between the groups. Data were collected from May 2021 to March 2022. The mean age of the patients in both groups was 48 (interquartile range, 36-60), and there were no appreciable differences in age or gender distribution between the two groups. The present study showed that a significant increase in the expression of ACE2, TMPRSS2, MMP-2, and MMP-9 genes in the severe type of the COVID-19 patients compared, to the mild type of the COVID-19 patients. Overall, it suggests the expression levels of these genes on the PBMC surface in the immune system are susceptible to infection by SARS-COV-2 and therefore could potentially predict the patients' outcome.

Hematological Profile with Peripheral Blood Smear Morphology of Admitted COVID-19 Infected Patients: A Study at a COVID Dedicated Hospital in Kashmir.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection started in Wuhan, China, and spread to the rest of the world to become a pandemic affecting over 385 million people throughout the world to date. Coronavirus disease 2019 (COVID-19) is primarily started as a respiratory tract infection. Recent studies indicate that it should be regarded as a systemic disease involving multiple systems including the hematopoietic system. Complete blood count and its parameters are important investigative tools in its prognosis. However, very few studies highlight the importance of peripheral blood cell morphology in this disease. AIM: To study the hematological parameters (complete blood count and peripheral blood film) of COVID-19-positive patients and to compare the hematological parameters of those admitted in intensive care units (ICUs) with those admitted in non-ICUs of the hospitals. MATERIALS AND METHODS: This retrospective study was carried out at a COVID-19 dedicated tertiary care center over a period of 3 months from July 2020 to September 2020. In our study, all 79 patients had complete blood counts performed at the time of admission. Complete blood count was repeated during the hospital stay for all severe cases. The data which provided information on the age and gender of each patient were obtained from the Laboratory Information System (LIS) of the hospital. RESULTS: The mean age of our study group was 46.05 years. Out of 79 cases, lymphopenia was seen in 16.5% with five patients presenting with severe lymphopenia (<0.5 × 109 /L). All the patients that required ICU care presented with moderate to severe lymphopenia. The patients in the ICU setting showed significant neutrophilia (mean 14.16 × 109 /L) on follow-up complete blood count. Thrombocytopenia was observed in 35.3% of cases. It was observed that the mean neutrophil- lymphocyte ratio was higher in ICU admitted patients as compared to the non-ICU admitted patients. Among the ICU patients, 80% showed a neutrophil-lymphocyte ratio above the baseline cutoff (3.1). A wide array of morphological changes were observed in the peripheral blood smear including toxic-like granules in neutrophils, fetus-like C-shaped nucleus, lymphoplasmacytoid cells, bizarre cells, and apoptotic cells. CONCLUSION: The study highlights that at the time of admission older age, decreased lymphocyte count, and raised neutrophil-lymphocyte ratio were closely associated with ICU admissions. Also, the morphological changes in peripheral blood film reveal atypical changes predominantly in the white blood cell (WBC) lineage.

Epigenetic immune monitoring for COVID-19 disease course prognosis.

Background: The course of COVID-19 is associated with severe dysbalance of the immune system, causing both leukocytosis and lymphopenia. Immune cell monitoring may be a powerful tool to prognosticate disease outcome. However, SARS-CoV-2 positive subjects are isolated upon initial diagnosis, thus barring standard immune monitoring using fresh blood. This dilemma may be solved by epigenetic immune cell counting. Methods: In this study, we used epigenetic immune cell counting by qPCR as an alternative way of quantitative immune monitoring for venous blood, capillary blood dried on filter paper (dried blood spots, DBS) and nasopharyngeal swabs, potentially allowing a home-based monitoring approach. Results: Epigenetic immune cell counting in venous blood showed equivalence with dried blood spots and with flow cytometrically determined cell counts of venous blood in healthy subjects. In venous blood, we detected relative lymphopenia, neutrophilia, and a decreased lymphocyte-to-neutrophil ratio for COVID-19 patients (n =103) when compared with healthy donors (n = 113). Along with reported sex-related differences in survival we observed dramatically lower regulatory T cell counts in male patients. In nasopharyngeal swabs, T and B cell counts were significantly lower in patients compared to healthy subjects, mirroring the lymphopenia in blood. Naïve B cell frequency was lower in severely ill patients than in patients with milder stages. Conclusions: Overall, the analysis of immune cell counts is a strong predictor of clinical disease course and the use of epigenetic immune cell counting by qPCR may provide a tool that can be used even for home-isolated patients.