Nadine Peart Akindele

Bio: Nadine Peart Akindele is an academic researcher from Johns Hopkins University School of Medicine. The author has contributed to research in topics: Medicine & Immunology. The author has an hindex of 2, co-authored 2 publications receiving 27 citations.

Acute covid-19 and multisystem inflammatory syndrome in children.

Abstract: ### What you need to know The most common symptoms in children with acute SARS-CoV-2 infection (covid-19 disease) are fever and cough. Other symptoms may include sore throat, rhinorrhoea, or congestion, myalgias, headache, fatigue, and gastrointestinal symptoms including nausea, vomiting, or diarrhoea. The range of symptom prevalence is reported from three large meta-analyses, one with 131 studies and 7780 paediatric patients,1 the second with 28 studies and 1614 patients,2 and the third with 46 studies and 551 patients3 and summarised in table 1. Though children have a similar distribution of initial symptoms as compared with adults, children are more likely to have mild, self-resolving symptoms without progression to the lower pulmonary disease that necessitates hospitalisation.4 Dermatological manifestations in children with mild disease are uncommon: acute infection has at times been associated with a maculopapular exanthem, but the pseudo chilblain lesions or “covid toes” seen in adults are rare.56 Although assessing the prevalence of loss of taste or smell among children may be challenging (especially when children …

Distinct Cytokine and Chemokine Dysregulation in Hospitalized Children With Acute Coronavirus Disease 2019 and Multisystem Inflammatory Syndrome With Similar Levels of Nasopharyngeal Severe Acute Respiratory Syndrome Coronavirus 2 Shedding.

Abstract: BACKGROUND: Multisystem Inflammatory Syndrome in Children (MIS-C) is a severe clinical phenotype of SARS-CoV-2 infection that remains poorly understood. METHODS: Hospitalized children <18 years of age with suspected COVID-19 (N=53) were recruited into a prospective cohort study; 32 had confirmed COVID-19, with 16 meeting the U.S. Centers for Disease Control criteria for MIS-C. Differences in nasopharyngeal viral RNA levels, SARS-CoV-2 seropositivity, and cytokine/chemokine profiles were examined, including after adjustments for age and sex. RESULTS: The median ages for those with and without MIS-C were 8.7 years (IQR 5.5-13.9) and 2.2 years (IQR 1.1-10.5), respectively, (p=0.18) and nasopharyngeal levels of SARS-CoV-2 RNA did not differ significantly between the two groups (median 63,848.25 copies/mL versus 307.1 copies/mL, p= 0.66); 75% of those with MIS-C were antibody positive compared to 44% without, p=0.026. Levels of 14 of 37 cytokines/chemokines (IL-1RA, IL-2RA, IL-6, IL-8, TNF-α, IL-10, IL-15, IL-18, MCP-1, IP-10, MIP-1α, MCP-2, MIP-1s, Eotaxin) were significantly higher in children with MIS-C compared to those without, irrespective of age or sex (FDR<0.05; p<0.05). CONCLUSIONS: The distinct pattern of heightened cytokine/chemokine dysregulation observed with MIS-C, compared with acute COVID-19, occurs across the pediatric age spectrum and with similar levels of nasopharyngeal SARS-CoV-2 RNA.

Continued Virus-Specific Antibody-Secreting Cell Production, Avidity Maturation and B Cell Evolution in Patients Hospitalized with COVID-19.

Abstract: Understanding the development and sustainability of the virus-specific protective immune response to infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) remains incomplete with respect to the appearance and disappearance of virus-specific antibody-secreting cells (ASCs) in circulation. Therefore, we performed cross-sectional and longitudinal analyses of peripheral blood mononuclear cells and plasma collected from 55 hospitalized patients up to 4 months after onset of COVID-19 symptoms. Spike (S)- and nucleocapsid (N)-specific IgM and IgG ASCs appeared within 2 weeks accompanied by flow cytometry increases in double negative plasmablasts consistent with a rapid extrafollicular B cell response. Total and virus-specific IgM and IgG ASCs peaked at 3-4 weeks and were still being produced at 3-4 months accompanied by increasing antibody avidity consistent with a slower germinal center B cell response. N-specific ASCs were produced for longer than S-specific ASCs and avidity maturation was greater for antibody to N than S. Patients with more severe disease produced more S-specific IgM and IgG ASCs than those with mild disease and had higher levels of N- and S-specific antibody. Women had more B cells in circulation than men and produced more S-specific IgA and IgG and N-specific IgG ASCs. Flow cytometry analysis of B cell phenotypes showed an increase in circulating B cells at 4-6 weeks with decreased percentages of switched and unswitched memory B cells. These data indicate ongoing antigen-specific stimulation, maturation, and production of ASCs for several months after onset of symptoms in patients hospitalized with COVID-19.

B-Cell Responses in Hospitalized Severe Acute Respiratory Syndrome Coronavirus 2–Infected Children With and Without Multisystem Inflammatory Syndrome

Abstract: Abstract Multisystem inflammatory syndrome in children (MIS-C) can complicate infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but differences in the immune responses during MIS-C compared to coronavirus disease 2019 (COVID-19) are poorly understood. We longitudinally compared the amounts and avidity of plasma anti-nucleocapsid (N) and spike (S) antibodies, phenotypes of B cells, and numbers of virus-specific antibody-secreting cells in circulation of children hospitalized with COVID-19 (n = 10) and with MIS-C (n = 12). N-specific immunoglobulin G (IgG) was higher early after presentation for MIS-C than COVID-19 patients and avidity of N- and S-specific IgG at presentation did not mature further during follow-up as it did for COVID-19. Both groups had waning proportions of B cells in circulation and decreasing but sustained production of virus-specific antibody-secreting cells for months. Overall, B-cell responses were similar, but those with MIS-C demonstrated a more mature antibody response at presentation compared to COVID-19, suggesting a postinfectious entity.

Effect of remdesivir post-exposure prophylaxis and treatment on pathogenesis of measles in rhesus macaques

Abstract: Measles is a systemic disease initiated in the respiratory tract with widespread measles virus (MeV) infection of lymphoid tissue. Mortality can be substantial, but no licensed antiviral therapy is available. We evaluated both post-exposure prophylaxis and treatment with remdesivir, a broad-spectrum antiviral, using a well-characterized rhesus macaque model of measles. Animals were treated with intravenous remdesivir for 12 days beginning either 3 days after intratracheal infection (post-exposure prophylaxis, PEP) or 11 days after infection at the onset of disease (late treatment, LT). As PEP, remdesivir lowered levels of viral RNA in peripheral blood mononuclear cells, but RNA rebounded at the end of the treatment period and infectious virus was continuously recoverable. MeV RNA was cleared more rapidly from lymphoid tissue, was variably detected in the respiratory tract, and not detected in urine. PEP did not improve clinical disease nor lymphopenia and reduced the antibody response to infection. In contrast, LT had little effect on levels of viral RNA or the antibody response but also did not decrease clinical disease. Therefore, remdesivir transiently suppressed expression of viral RNA and limited dissemination when provided as PEP, but virus was not cleared and resumed replication without improvement in the clinical disease parameters evaluated.

Multisystem inflammatory syndrome in children and Kawasaki disease: a critical comparison.

Abstract: Children and adolescents infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are predominantly asymptomatic or have mild symptoms compared with the more severe coronavirus disease 2019 (COVID-19) described in adults. However, SARS-CoV-2 is also associated with a widely reported but poorly understood paediatric systemic vasculitis. This multisystem inflammatory syndrome in children (MIS-C) has features that overlap with myocarditis, toxic-shock syndrome and Kawasaki disease. Current evidence indicates that MIS-C is the result of an exaggerated innate and adaptive immune response, characterized by a cytokine storm, and that it is triggered by prior SARS-CoV-2 exposure. Epidemiological, clinical and immunological differences classify MIS-C as being distinct from Kawasaki disease. Differences include the age range, and the geographical and ethnic distribution of patients. MIS-C is associated with prominent gastrointestinal and cardiovascular system involvement, admission to intensive care unit, neutrophilia, lymphopenia, high levels of IFNγ and low counts of naive CD4+ T cells, with a high proportion of activated memory T cells. Further investigation of MIS-C will continue to enhance our understanding of similar conditions associated with a cytokine storm.

Hyperinflammatory Immune Response and COVID-19: A Double Edged Sword.

Abstract: The coronavirus disease-19 (COVID-19) elicited by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused devastating health, economic and social impact worldwide. Its clinical spectrum ranges from asymptomatic to respiratory failure and multi-organ failure or death. The pathogenesis of SARS-CoV-2 infection is attributed to a complex interplay between virus and host immune response. It involves activation of multiple inflammatory pathways leading to hyperinflammation and cytokine storm, resulting in tissue damage, acute respiratory distress syndrome (ARDS) and multi-organ failure. Accumulating evidence has raised concern over the long-term health effects of COVID-19. Importantly, the neuroinvasive potential of SARS-CoV-2 may have devastating consequences in the brain. This review provides a conceptual framework on how the virus tricks the host immune system to induce infection and cause severe disease. We also explore the key differences between mild and severe COVID-19 and its short- and long-term effects, particularly on the human brain.

Safety and immunogenicity of a recombinant adenovirus type-5-vectored COVID-19 vaccine with a homologous prime-boost regimen in healthy participants aged 6 years and above: a randomised, double-blind, placebo-controlled, phase 2b trial.

Abstract: Background We assessed the safety and immunogenicity of a recombinant adenovirus type-5 (Ad5)-vectored COVID-19 vaccine with homologous prime-boost regimens in healthy participants aged 6 years and above. Methods In this randomised, double-blind, placebo-controlled trial, participants received low-dose vaccine, middle-dose vaccine or placebo. Prime-booster regimens were given intramuscularly 56 days apart. ELISA antibodies to the receptor binding domain (RBD) and pseudovirus neutralising antibodies were detected. Adverse events were monitored for 28 days following each vaccination. Results A total of 430 participants were enrolled in the study, with 30 participants aged 18-55 years (MID cohort), 250 participants aged 56 years and older (OLD cohort), and 150 participants aged 6-17 years (MIN cohort). Ad5-vectored COVID-19 vaccine induced significant RBD-specific ELISA antibodies which decreased with increasing age, with geometric mean titres (GMTs) of 1037.5 in MIN cohort, 647.2 in MID cohort, and 338.0 in OLD cohort receiving 5×10 10 viral particles on day 28 following boost vaccination. Pseudovirus neutralising antibodies showed a similar pattern, with GMTs of 168.0 in MIN cohort, 76.8 in MID cohort, and 79.7 in OLD cohort. A single dose in children and adolescents induced higher antibody responses than that elicited by two doses in adults, with GMTs of 1091.6 and 96.6 in ELISA antibody and neutralising antibody, respectively. Homologous prime-boost vaccination was safety and tolerable. Conclusions Ad5-vectored COVID-19 vaccine with a single dose was safe and induced robust immune responses in children and adolescents aged 6-17 years. A prime-boost regimen needs further exploration for Ad5-vectored COVID-19 vaccine.