{"id":110690,"date":"2025-05-18T03:31:10","date_gmt":"2025-05-18T03:31:10","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/110690\/"},"modified":"2025-05-18T03:31:10","modified_gmt":"2025-05-18T03:31:10","slug":"babies-fight-covid-differently-than-anyone-else","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/110690\/","title":{"rendered":"Babies Fight COVID Differently Than Anyone Else"},"content":{"rendered":"<p><strong>Summary: <\/strong>Infants hospitalized with severe COVID-19 mount an immune response that looks entirely different from that of adults or older children. Researchers found both interferon responses and inflammation were elevated simultaneously\u2014something never before observed in other viral infections.<\/p>\n<p>T and B cells in these infants were still na\u00efve yet highly activated, and some even produced their own strong antibody responses, surprising scientists given their age. These findings suggest that infants\u2019 immune systems operate on distinct principles and may require age-specific strategies for treatment and prevention.<\/p>\n<p><strong>Key Facts:<\/strong><\/p>\n<ul class=\"wp-block-list\">\n<li><strong>Dual Activation:<\/strong> Infants showed simultaneous high interferon and inflammation\u2014unusual in viral infections.<\/li>\n<li><strong>Na\u00efve but Active:<\/strong> Despite never encountering infection, infants\u2019 T and B cells were strongly activated.<\/li>\n<li><strong>Independent Antibodies:<\/strong> Some infants produced robust SARS-CoV-2 antibodies, despite relying on maternal immunity.<\/li>\n<\/ul>\n<p><strong>Source: <\/strong>St. Jude Children\u2019s Research Hospital<\/p>\n<p><strong>Infants hospitalized with severe COVID-19 have significantly different immune responses than adults or older children. <\/strong><\/p>\n<p>The finding comes from scientists at St. Jude Children\u2019s Research Hospital, The Jackson Laboratory for Genomic Medicine, Weill Cornell Medicine, Nationwide Children\u2019s Hospital, Icahn School of Medicine at Mt. Sinai and Yale University.<\/p>\n<p>The researchers established the unique features of hospitalized infants\u2019 immune cells during mild, moderate and severe COVID-19. The study may help identify better ways to protect infants from the disease.<\/p>\n<p>It was published today in\u00a0Nature Communications.\u00a0<\/p>\n<p>\u201cThis is one of the first studies to characterize the immune response in young infants hospitalized with severe COVID-19 with high-resolution,\u201d said co-corresponding author\u00a0Octavio Ramilo, MD, St. Jude\u00a0Department of Infectious Diseases\u00a0chair.<\/p>\n<p>\u201cWe found that the infant immune system\u2019s response to SARS-CoV-2 looks nothing like the immune response at any other age, highlighting the need to study infants, specifically, if we want to prevent severe infections and understand the unique features of the infant immune system.\u201d\u00a0<\/p>\n<p>The collaborators studied immune cells from infants ranging from a few weeks to 16 months old who were hospitalized with mild, moderate or severe disease. They compared those cells to immune cells from healthy infants and a published cohort of adults hospitalized with COVID-19.<\/p>\n<p>Monocytes (a type of white blood cell) from hospitalized infants appeared to have some similar features to those in adults infected with SARS-CoV-2. However, two other major white blood cell types, T and B cells, looked very different than in any other group. Hospitalized infants had more CD4 T cells.<\/p>\n<p>Additionally, both T and B cells were still activated despite being largely na\u00efve, having never encountered an infection. These infants\u2019 T and B cells also expressed the antiviral interferon response, which led to high expression of interferon-stimulated genes at a much higher level than in older children or adults.\u00a0<\/p>\n<p><strong>Conflicting signals from the infant immune system\u00a0<\/strong><\/p>\n<p>Almost all infant immune cells expressed high levels of interferon-stimulated genes. At the same time, when the collaborators tested blood from these infants, they found high levels of inflammation-causing molecules (inflammatory cytokines), which differs from previous observations in infants with mild infection.<\/p>\n<p>These findings challenge previous beliefs about infant immune responses to SARS-CoV-2.\u00a0<\/p>\n<p>\u201cNormally, we think about the interferon and inflammation systems being in balance with each other,\u201d said co-first author\u00a0M. Asunci\u00f3n Mej\u00edas, MD, PhD, St. Jude Department of Infectious Diseases.<\/p>\n<p>\u201cIf one is upregulated, the other is downregulated. But what we found was different. In infants, both systems were upregulated in the same cells, monocytes, which we\u2019ve never seen before in other respiratory viral infections.\u201d\u00a0<\/p>\n<p>The scientists identified the differences in these infants\u2019 immune responses through single-cell RNA sequencing of white blood cells. RNA is a copy of instructions from DNA that lets cells express genes.<\/p>\n<p>By looking at the RNA from individual cells, the researchers found the features unique to infants and compared them by disease severity. They found more severe disease associated with higher interferon and interferon-stimulated gene expression. High levels of inflammatory cytokines also correlated with more severe disease.\u00a0<\/p>\n<p>\u201cIt\u2019s unclear whether these high levels of interferon, interferon-stimulated genes and inflammatory cytokines are protecting those with severe disease or contributing to it,\u201d Ramilo said.<\/p>\n<p>\u201cBut they are clearly playing a critical role, which will require further studies.\u201d\u00a0<\/p>\n<p><strong>Understanding infant antibody response is a field in its infancy\u00a0<\/strong><\/p>\n<p>B cells produce specialized molecules called antibodies that target particular parts of viruses, bind to them and stop infections. An infant typically relies on their mother\u2019s antibodies until they are about 6 months old.<\/p>\n<p>During the pandemic, the researchers examined whether a mother\u2019s immunity to non-SARS coronaviruses, which cause the common cold, would help protect infants.\u00a0<\/p>\n<p>\u201cWe found that these infants made a strong and robust new antibody response to SARS-CoV-2,\u201d said Mej\u00edas.<\/p>\n<p>\u201cTheir pre-existing maternal antibodies against the endemic coronaviruses did not block infection at all.\u201d<\/p>\n<p>The finding was surprising; some infants were as young as just a few weeks old and still created an antibody response to the virus. Infants are typically much older before they begin building such responses for other respiratory viruses.<\/p>\n<p>The children in the study also lacked anti-interferon antibodies, which have been associated with severe COVID-19 in adults, emphasizing that lessons from adult immunity may not translate to infant immune responses.\u00a0<\/p>\n<p>\u201cWe showed that these hospitalized infants responded to SARS-CoV-2, but differently than anyone else,\u201d Ramilo said. \u201cAs COVID-19 is now an endemic disease, we need to understand the unique features of the infant immune system better so we can find ways to help these babies through such infections during their first months of life.\u201d\u00a0<\/p>\n<p><strong>Authors and funding\u00a0<\/strong><\/p>\n<p>The study\u2019s other first author is Djamel Nehar-Belaid of The Jackson Laboratory for Genomic Medicine. The study\u2019s other co-corresponding authors are Jacques Banchereau, The Jackson Laboratory for Genomic Medicine, and Virginia Pascual, Weill Cornell Medicine.<\/p>\n<p>The study\u2019s other authors are Zhaohui Xu, St. Jude; Radu Marches, Rushil Yerrabelli, Guo Chen and Duygu Ucar, The Jackson Laboratory for Genomic Medicine; Pablo S\u00e1nchez, Sara Mertz and Fang Ye, Nationwide Children\u2019s Hospital; John Tsang, Yale University and Chan Zuckerberg Biohub and Teresa Aydillo, Lisa Miorin, Anastasija Cupic and Adolfo Garc\u00eda-Sastre, Icahn School of Medicine at Mount Sinai.\u00a0<\/p>\n<p><strong>Funding: <\/strong>The study was supported by grants from the National Institutes of Health (JAX Cancer Center P30CA034196, U01AI131386, U19AI135972, U19AI142733 and U19AI168631), start-up funds from the Jackson Laboratory, CRIPT (Center for Research on Influenza Pathogenesis and Transmission), National Institute of Allergy and Infectious Diseases (Center of Excellence for Influenza Research and Response contract #75N93021C00014) and ALSAC, the fundraising and awareness organization of St. Jude.\u00a0<\/p>\n<p>About this COVID-19 and neurodevelopment research news<\/p>\n<p class=\"has-background\" style=\"background-color:#ffffe8\"><strong>Author: <\/strong><a href=\"http:\/\/neurosciencenews.com\/cdn-cgi\/l\/email-protection#f895919b90999d94d68b909d9e9e919d949cb88b8c928d9c9dd6978a9f\" target=\"_blank\" rel=\"noreferrer noopener\">Michael Sheffield<\/a><br \/><strong>Source: <\/strong><a href=\"https:\/\/stjude.org\" target=\"_blank\" rel=\"noreferrer noopener\">St. Jude Children\u2019s Research Hospital<\/a><br \/><strong>Contact: <\/strong>Michael Sheffield \u2013 St. Jude Children\u2019s Research Hospital<br \/><strong>Image: <\/strong>The image is credited to Neuroscience News<\/p>\n<p class=\"has-background\" style=\"background-color:#ffffe8\"><strong>Original Research: <\/strong>Open access.<br \/>\u201c<a href=\"https:\/\/www.nature.com\/articles\/s41467-025-59411-z\" target=\"_blank\" rel=\"noreferrer noopener\">Immune perturbations induced by SARS-CoV2 in infants vary with disease severity and differ from adults\u2019 responses<\/a>\u201d by Octavio Ramilo et al. Nature Communications<\/p>\n<p><strong>Abstract<\/strong><\/p>\n<p><strong>Immune perturbations induced by SARS-CoV2 in infants vary with disease severity and differ from adults\u2019 responses<\/strong><\/p>\n<p>Differences in immune profiles of children and adults with COVID-19 have been previously described. However, no systematic studies have been reported from infants hospitalized with severe disease.<\/p>\n<p>We applied a multidimensional approach to decipher the immune responses of SARS-CoV-2 infected infants (n\u2009=\u200926; 10 subacute, 11 moderate and 5 severe disease; median age\u2009=\u20091.6 months) and matched controls (n\u2009=\u200914; median age\u2009=\u20092 months).<\/p>\n<p>Single cell (scRNA-seq) profiling of PBMCs revealed substantial alterations in cell composition in SARS-CoV-2 infected infants; with most cell-types switching to an interferon-stimulated gene (ISGhi) state including: (i) CD14+\u00a0monocytes co-expressing ISGs and inflammasome-related molecules, (ii) ISGhi\u00a0naive CD4+\u00a0T cells, (iii) ISGhi\u00a0proliferating cytotoxic CD8+\u00a0T cells, and (iv) ISGhi\u00a0naive and transitional B cells.<\/p>\n<p>We observe increased serum concentrations of both interferons and inflammatory cytokines in infected infants.<\/p>\n<p>Antibody responses to SARS-CoV-2 are also consistently detected in the absence of anti-IFN autoantibodies. Compared with infected adults, infants display a similar ISG signature in monocytes but a markedly enhanced ISG signature in T and B cells.<\/p>\n<p>These findings provide insights into the distinct immune responses to SARS-CoV-2 in the first year of life and underscore the importance of further defining the unique features of early life immunity.<\/p>\n","protected":false},"excerpt":{"rendered":"Summary: Infants hospitalized with severe COVID-19 mount an immune response that looks entirely different from that of adults&hellip;\n","protected":false},"author":2,"featured_media":110691,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[648,215,1117,649,105,2667,2407,219,654,233,220,50212,16,15],"class_list":{"0":"post-110690","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-brain-development","9":"tag-brain-research","10":"tag-covid-19","11":"tag-developmental-neuroscience","12":"tag-health","13":"tag-immune-system","14":"tag-inflammation","15":"tag-neurobiology","16":"tag-neurodevelopment","17":"tag-neurology","18":"tag-neuroscience","19":"tag-st-jude-childrens-research-hospital","20":"tag-uk","21":"tag-united-kingdom"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/114526727944193157","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/110690","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=110690"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/110690\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/110691"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=110690"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=110690"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=110690"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}