Mikko Seppänen
A5083971519- Immunodeficiency and Autoimmune Disorders
- Blood disorders and treatments
- Immune Cell Function and Interaction
- T-cell and B-cell Immunology
- interferon and immune responses
- Respiratory viral infections research
- Parvovirus B19 Infection Studies
- SARS-CoV-2 and COVID-19 Research
- NF-κB Signaling Pathways
- Diabetes and associated disorders
- Immune Response and Inflammation
- Herpesvirus Infections and Treatments
- Inflammasome and immune disorders
- Complement system in diseases
- Mycobacterium research and diagnosis
- Pediatric health and respiratory diseases
- Tracheal and airway disorders
- Research in Social Sciences
- COVID-19 Clinical Research Studies
- Cystic Fibrosis Research Advances
- Viral Infections and Vectors
- Chronic Lymphocytic Leukemia Research
- RNA regulation and disease
- Viral Infections and Immunology Research
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
Helsinki University Hospital
2016-2025
University of Helsinki
2016-2025
ERN GUARD-Heart
2024
ERN RITA
2024
Loma Linda University Medical Center
2024
Loma Linda University
2024
National Institute of Allergy and Infectious Diseases
2024
National Institutes of Health
2024
National Institute of Diabetes and Digestive and Kidney Diseases
2024
National Heart Lung and Blood Institute
2024
Abstract We report the updated classification of inborn errors immunity, compiled by International Union Immunological Societies Expert Committee. This documents key clinical and laboratory features 55 novel monogenic gene defects, 1 phenocopy due to autoantibodies, that have either been discovered since previous update (published January 2020) or were characterized earlier but confirmed expanded in subsequent studies. While variants additional genes associated with immune diseases reported...
Autoimmune polyendocrine syndrome type 1 (APS-1) is a life-threatening, autosomal recessive caused by autoimmune regulator (AIRE) deficiency. In APS-1, self-reactive T cells escape thymic negative selection, infiltrate organs, and drive injury. The effector mechanisms governing T-cell-mediated damage in APS-1 remain poorly understood.
This report provides an updated classification of inborn errors immunity (IEIs) involving 508 different genes and 17 phenocopies. Of these, we 67 novel monogenic defects 2 phenocopies due to neutralizing anti-cytokine autoantibodies or somatic mutations, which either have been discovered since the previous update (published June 2022) were reported earlier but recently confirmed and/or expanded. The new additions made after rigorous review genetic descriptions IEIs by International Union...
<h3>Objective:</h3> To determine the proportion of children with herpes simplex encephalitis (HSE) displaying TLR3 deficiency, extent allelic heterogeneity, and specific clinical features deficiency. <h3>Methods:</h3> We determined sequence all exons <i>TLR3</i> in 110 120 patients HSE enrolled our study who do not carry any previously described HSE-predisposing mutations pathway genes (<i>TLR3</i>, <i>UNC93B1</i>, <i>TRIF</i>, <i>TRAF3</i>, <i>TBK1</i>). All new mutant alleles detected were...
BackgroundRecent findings strongly support hematopoietic stem cell transplantation (HSCT) in patients with severe presentation of LPS-responsive beige-like anchor protein (LRBA) deficiency, but long-term follow-up and survival data beyond previous patient reports or meta-reviews are scarce for those who do not receive a transplant.ObjectiveThis international retrospective study was conducted to elucidate the longitudinal clinical course LRBA deficiency transplant.MethodWe assessed disease...
Abstract Clonal hematopoiesis driven by somatic heterozygous TET2 loss is linked to malignant degeneration via consequent aberrant DNA methylation, and possibly cardiovascular disease increased cytokine chemokine expression as reported in mice. Here, we discover a germline mutation lymphoma family. We observe neither unusual predisposition atherosclerosis nor abnormal pro-inflammatory or expression. The latter finding confirmed cells from three additional unrelated carriers. defect elevates...
The association between cancer and autoimmune disease is unexplained, exemplified by T cell large granular lymphocytic leukemia (T-LGL) where gain-of-function (GOF) somatic STAT3 mutations correlate with co-existing autoimmunity. To investigate whether these are the cause or consequence of CD8+ clonal expansions autoimmunity, we analyzed patients mice germline GOF mutations. drove accumulation effector clones highly expressing NKG2D, receptor for stress-induced MHC-class-I-related molecules....
The molecular basis of interindividual clinical variability upon infection with Staphylococcus aureus is unclear. We describe patients haploinsufficiency for the linear deubiquitinase OTULIN, encoded by a gene on chromosome 5p. Patients suffer from episodes life-threatening necrosis, typically triggered S. infection. disorder phenocopied in 5p- (Cri-du-Chat) chromosomal deletion syndrome. OTULIN causes an accumulation ubiquitin dermal fibroblasts, but tumor necrosis factor receptor-mediated...
X-linked recessive deficiency of TLR7, a MyD88- and IRAK-4–dependent endosomal ssRNA sensor, impairs SARS-CoV-2 recognition type I IFN production in plasmacytoid dendritic cells (pDCs), thereby underlying hypoxemic COVID-19 pneumonia with high penetrance. We report 22 unvaccinated patients autosomal MyD88 or IRAK-4 infected (mean age: 10.9 yr; 2 mo to 24 yr), originating from 17 kindreds eight countries on three continents. 16 were hospitalized: six moderate, four severe, critical pneumonia,...
Mutations in the CERC1 gene associated with deficiency ADA2 protein (DADA2) have been implicated pathogenesis of cutaneous polyarteritis nodosa (cPAN) and early-onset vasculopathy. DADA2 is not only limited to cPAN vasculopathy but also includes immunodeficiency that affects several cellular compartments, including B cells; however, some patients appear a more indolent, skin-limited disease.In this report, we describe 2 white siblings (female male) history as result novel compound...