title: IL-7δ5 protein is expressed in human tissues and induces expression of the oxidized low density lipoprotein receptor 1 (OLR1) in CD14+ monocytes.
abstract: OBJECTIVE
  The 6-exon-spanning 'canonical' Interleukin-7 (IL-7c) is a non-redundant cytokine in human T-cell homeostasis that undergoes extensive alternative pre-mRNA splicing. The IL-7 gene variant lacking, exon 5 (IL-7δ5), exhibits agonistic effects as compared to IL-7c. We studied in this report for the first time the protein expression of IL-7δ5 variant in tissues and its role in monocyte activation.
  
  
  METHODS
  We visualized the expression of IL-7δ5 protein by immunohistochemistry in both healthy and malignant (human) tissues and investigated the impact of IL-7δ5 stimulation on CD14+ monocytes using gene expression analysis and flow cytometry.
  
  
  RESULTS
  IL-7δ5 is largely expressed by human epithelial cells, yet also by stromal cells in malignant lesions. Gene expression analysis in CD14+ monocytes, induced by the 6-exon spanning IL-7 or IL-7δ5 showed similar changes resulting in a pro-inflammatory phenotype and increased expression of genes involved in lipid metabolism. IL7δ5 was superior in inducing upregulation of the oxidised low density lipoprotein receptor (OLR), measured by flow cytometry, in CD14+ cells.
  
  
  CONCLUSIONS
  IL-7δ5, produced from non-transformed and transformed cells, may contribute to chronic inflammatory responses and development of 'foamy' cells by increased OLR1 expression that mediates increased oxLDL uptake.
authors.affiliation: Department of Microbiology Tumor and Cell Biology (MTC), Karolinska Institute, 171 77, Stockholm, Sweden. Electronic address: Lalit.Rane@uib.no.
authors.forename: Lalit
authors.initials: L
authors.lastname: Rane
authors.affiliation: Center for Infectious Medicine (CIM), Karolinska Institute, 141 86 Stockholm, Sweden. Electronic address: Rahman.sayma07@gmail.com.
authors.forename: Sayma
authors.initials: S
authors.lastname: Rahman
authors.affiliation: Division of Therapeutic Immunology (TIM), Department of Labroratory Medicine, Karolinska Institute, 141 86, Stockholm, Sweden. Electronic address: Isabelle.Magalhaes@ki.se.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Magalhaes
authors.affiliation: Division of Therapeutic Immunology (TIM), Department of Labroratory Medicine, Karolinska Institute, 141 86, Stockholm, Sweden; Department of Medicine, Karolinska Institute, 141 86, Stockholm, Sweden. Electronic address: Ambati@stanford.edu.
authors.forename: Aditya
authors.initials: A
authors.lastname: Ambati
authors.affiliation: Center for Infectious Medicine (CIM), Karolinska Institute, 141 86 Stockholm, Sweden. Electronic address: Jan.Andersson@ki.se.
authors.forename: Jan
authors.initials: J
authors.lastname: Andersson
authors.affiliation: Centre for Clinical Microbiology, Division of Infection and Immunity, University College London, and NIHR Biomedical Research Centre, UCL Hospitals NHS Foundation Trust, London, United Kingdom. Electronic address: a.zhumla@ucl.ac.uk.
authors.forename: Alimuddin
authors.initials: A
authors.lastname: Zumla
authors.affiliation: Center for Infectious Medicine (CIM), Karolinska Institute, 141 86 Stockholm, Sweden. Electronic address: Susanna.Brighenti@ki.se.
authors.forename: Susanna
authors.initials: S
authors.lastname: Brighenti
authors.affiliation: Department of Microbiology Tumor and Cell Biology (MTC), Karolinska Institute, 171 77, Stockholm, Sweden; Division of Therapeutic Immunology (TIM), Department of Labroratory Medicine, Karolinska Institute, 141 86, Stockholm, Sweden. Electronic address: Markus.Maeurer@ki.se.
authors.forename: Markus J
authors.initials: MJ
authors.lastname: Maeurer
mesh_terms: D016207:Cytokines / Q000032:analysis* / Q000276:immunology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D015851:Interleukin-7 / Q000276:immunology / Q000378:metabolism*; D018950:Lipopolysaccharide Receptors / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000378:metabolism; D009000:Monocytes / Q000276:immunology; D020411:Oligonucleotide Array Sequence Analysis; D051127:Scavenger Receptors, Class E / Q000235:genetics / Q000378:metabolism*
chemical_list: D016207:Cytokines; C508605:IL7 protein, human; D015851:Interleukin-7; D018950:Lipopolysaccharide Receptors; D008077:Lipoproteins, LDL; C495137:OLR1 protein, human; D051127:Scavenger Receptors, Class E; C099252:oxidized low density lipoprotein
keywords: 5 protein; IL-7&delta; Interleukin-7; M. tuberculosis; OLR1; Tuberculosis; alternative splicing