title: Skin barrier dysfunction and low antimicrobial peptide expression in cutaneous T-cell lymphoma.
abstract: OBJECTIVE
  Atopic dermatitis is characterized by decreased expression of filaggrin and loricrin. Patients with atopic dermatitis often suffer from skin infections, which are also frequently seen in patients with cutaneous T-cell lymphoma (CTCL). In this study, we aimed to investigate the skin barrier in CTCL.
  
  
  METHODS
  We assessed skin moisture and transepidermal water loss (TEWL) in patients with CTCL. We next examined mRNA expression levels of filaggrin, loricrin, and antimicrobial peptides (AMP) in skin samples of CTCL, using skin from healthy volunteers and patients with atopic dermatitis or psoriasis as controls. Immunostainings for filaggrin, loricrin, and S100 proteins were also performed.
  
  
  RESULTS
  Lower levels of skin moisture accompanied by higher levels of TEWL were seen in lesional skin of CTCL than in normal skin. CTCL lesional skin contained lower levels of filaggrin and loricrin mRNA than normal skin, which was also true with atopic dermatitis and psoriatic skin. mRNA expression levels of filaggrin in CTCL skin negatively correlated with disease severity markers. Expression levels of AMPs in lesional skin of CTCL and atopic dermatitis were significantly lower than in psoriatic skin. Immunohistochemistry confirmed decreased expression of filaggrin and loricrin in CTCL, atopic dermatitis, and psoriatic skin and enhanced expression of S100 proteins in psoriatic skin.
  
  
  CONCLUSIONS
  Our results show that there is barrier dysfunction in CTCL skin, similar to what is seen with atopic dermatitis skin. In addition, low AMP expression in CTCL skin was documented when compared with psoriatic skin, which may explain frequent infections that can occur in patients with CTCL.
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Hiraku
authors.initials: H
authors.lastname: Suga
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan sugayam-der@h.u-tokyo.ac.jp.
authors.forename: Makoto
authors.initials: M
authors.lastname: Sugaya
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Tomomitsu
authors.initials: T
authors.lastname: Miyagaki
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Hanako
authors.initials: H
authors.lastname: Ohmatsu
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Kawaguchi
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Naomi
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Fujita
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Asano
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Tada
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kadono
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sato
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D000091344:Filaggrin Proteins; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism; D016410:Lymphoma, T-Cell, Cutaneous / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D009418:S100 Proteins / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000503:physiopathology*; D012871:Skin Diseases / Q000378:metabolism* / Q000473:pathology*; D014870:Water Loss, Insensible / Q000502:physiology*
chemical_list: D023181:Antimicrobial Cationic Peptides; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D008565:Membrane Proteins; D012333:RNA, Messenger; D009418:S100 Proteins; C064554:loricrin