title: Characterisation of subpopulations of myeloid cells in infantile haemangioma.
abstract: OBJECTIVE
  Cells expressing markers of mast cells, macrophages and dendritic cells have previously been demonstrated within the interstitium of infantile haemangioma (IH). This study characterised these myeloid cellular subpopulations within IH.
  
  
  METHODS
  Immunohistochemical staining was performed on proliferating and involuted IHs for the expression of Nanog, tryptase, CD163, DC-SIGN and CD45. The presence of mRNA corresponding to Nanog, tryptase α/β-1, tryptase β-2, CD163 and DC-SIGN was confirmed by NanoString and RT-PCR in snap-frozen IH tissues.
  
  
  RESULTS
  Immunohistochemical staining showed expression of Nanog by interstitial phenotypical mast cells within proliferating IH, which were separate from the interstitial M2-polarised macrophages that also expressed DC-SIGN, a dendritic cell marker. These two myeloid cellular subpopulations in IH did not express the pan-haematopoietic marker, CD45.
  
  
  CONCLUSIONS
  There are two interstitial subpopulations of myeloid cells within IH: phenotypical mast cells which also express Nanog, indicating a primitive phenotype; and M2-polarised macrophages which also express DC-SIGN.
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand.
authors.forename: Elysia M S
authors.initials: EM
authors.lastname: Tan
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand.
authors.forename: Daria A
authors.initials: DA
authors.lastname: Chudakova
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Davis
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand.
authors.forename: Helen D
authors.initials: HD
authors.lastname: Brasch
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand.
authors.forename: Tinte
authors.initials: T
authors.lastname: Itinteang
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand Centre for the Study & Treatment of Vascular Birthmarks, Wellington Regional Plastic, Maxillofacial & Burns Unit, Hutt Hospital, Wellington, New Zealand.
authors.forename: Swee T
authors.initials: ST
authors.lastname: Tan
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics; D049109:Cell Proliferation; D002648:Child; D015972:Gene Expression Regulation, Neoplastic; D006391:Hemangioma / Q000737:chemistry* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008264:Macrophages / Q000737:chemistry* / Q000145:classification / Q000473:pathology; D008407:Mast Cells / Q000737:chemistry* / Q000145:classification / Q000473:pathology; D010641:Phenotype; D012333:RNA, Messenger / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; D012333:RNA, Messenger
keywords: HISTOPATHOLOGY; PAEDIATRIC PATHOLOGY; VASCULAR TUMOURS