{"title":"Heterozygous missense CSF1R variants hamper in vitro CD34+-derived dendritic cell generation but not in vivo dendritic cell development","authors":"","doi":"10.1016/j.molimm.2024.08.002","DOIUrl":null,"url":null,"abstract":"<div><p>Colony stimulating factor 1 receptor (CSF1R) is an essential receptor for both colony stimulating factor 1 (CSF1) and interleukin (IL) 34 signaling expressed on monocyte precursors and myeloid cells, including monocytes, dendritic cells (DC), and microglia. In humans, dominant heterozygous pathogenic variants in <em>CSF1R</em> cause a neurological condition known as CSF1R-related disorder (CSF1R-RD), typically with late onset, previously referred to as adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP). CSF1R-RD is characterized by microglia reduction and altered monocyte function; however, the impact of pathogenic <em>CSF1R</em> variants on the human DC lineage remains largely unknown.</p><p>We previously reported that cord blood CD34+ stem cell-derived DCs generated <em>in vitro</em> originate specifically from CSF1R expressing precursors. In this study, we examined the DC lineage of four unrelated patients with late-onset CSF1R-RD who carried heterozygous missense <em>CSF1R</em> variants (c.2330G>A, c.2375C>A, c.2329C>T, and c.2381T>C) affecting different amino acids in the protein tyrosine kinase domain of CSF1R. CD34+ stem cells and CD14+ monocytes were isolated from peripheral blood and subjected to an <em>in vitro</em> culture protocol to differentiate towards conventional DCs and monocyte-derived DCs, respectively. Flow cytometric analysis revealed that monocytes from patients with late-onset CSF1R-RD were still able to differentiate into monocyte-derived DCs <em>in vitro</em>, whereas the ability of CD34+ stem cells to differentiate into conventional DCs was impaired. Strikingly, the peripheral blood of patients contained all naturally occurring DC subsets. We conclude that the <em>in vitro</em> abrogation of DC-development in patients with heterozygous pathogenic missense <em>CSF1R</em> variants does not translate to an impairment in DC development <em>in vivo</em> and speculate that CSF1R signalling <em>in vivo</em> is compensated, which needs further study.</p></div>","PeriodicalId":18938,"journal":{"name":"Molecular immunology","volume":null,"pages":null},"PeriodicalIF":3.2000,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0161589024001585/pdfft?md5=0ee273246aee58fdb03ae182cfc87876&pid=1-s2.0-S0161589024001585-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular immunology","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0161589024001585","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Colony stimulating factor 1 receptor (CSF1R) is an essential receptor for both colony stimulating factor 1 (CSF1) and interleukin (IL) 34 signaling expressed on monocyte precursors and myeloid cells, including monocytes, dendritic cells (DC), and microglia. In humans, dominant heterozygous pathogenic variants in CSF1R cause a neurological condition known as CSF1R-related disorder (CSF1R-RD), typically with late onset, previously referred to as adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP). CSF1R-RD is characterized by microglia reduction and altered monocyte function; however, the impact of pathogenic CSF1R variants on the human DC lineage remains largely unknown.
We previously reported that cord blood CD34+ stem cell-derived DCs generated in vitro originate specifically from CSF1R expressing precursors. In this study, we examined the DC lineage of four unrelated patients with late-onset CSF1R-RD who carried heterozygous missense CSF1R variants (c.2330G>A, c.2375C>A, c.2329C>T, and c.2381T>C) affecting different amino acids in the protein tyrosine kinase domain of CSF1R. CD34+ stem cells and CD14+ monocytes were isolated from peripheral blood and subjected to an in vitro culture protocol to differentiate towards conventional DCs and monocyte-derived DCs, respectively. Flow cytometric analysis revealed that monocytes from patients with late-onset CSF1R-RD were still able to differentiate into monocyte-derived DCs in vitro, whereas the ability of CD34+ stem cells to differentiate into conventional DCs was impaired. Strikingly, the peripheral blood of patients contained all naturally occurring DC subsets. We conclude that the in vitro abrogation of DC-development in patients with heterozygous pathogenic missense CSF1R variants does not translate to an impairment in DC development in vivo and speculate that CSF1R signalling in vivo is compensated, which needs further study.
期刊介绍:
Molecular Immunology publishes original articles, reviews and commentaries on all areas of immunology, with a particular focus on description of cellular, biochemical or genetic mechanisms underlying immunological phenomena. Studies on all model organisms, from invertebrates to humans, are suitable. Examples include, but are not restricted to:
Infection, autoimmunity, transplantation, immunodeficiencies, inflammation and tumor immunology
Mechanisms of induction, regulation and termination of innate and adaptive immunity
Intercellular communication, cooperation and regulation
Intracellular mechanisms of immunity (endocytosis, protein trafficking, pathogen recognition, antigen presentation, etc)
Mechanisms of action of the cells and molecules of the immune system
Structural analysis
Development of the immune system
Comparative immunology and evolution of the immune system
"Omics" studies and bioinformatics
Vaccines, biotechnology and therapeutic manipulation of the immune system (therapeutic antibodies, cytokines, cellular therapies, etc)
Technical developments.