Surfactant protein expression in human skin: evidence and implications.
The presence of surfactant proteins (SPs), critical to local barrier and defense functions and usually associated with the lung, was revealed in adult and fetal human skin complementary deoxyribonucleic acid, in skin samples from three adult female donors and also in cultured fibroblasts, keratinocytes, and melanocytes. Using reverse transcription-PCR, SP-A, SP-B, SP-C, and SP-D messenger ribonucleic acid expression was detected to varying extents in the different skin sources. The stronger expression of SP-C in fetal skin, compared to adult skin, suggested that the role of this protein alters with age. Immunohistochemical studies showed variable distribution of SPs in human epidermis and dermis, confirming that these proteins are indeed translated and expressed in skin tissue. In vitro studies showed that the surface tension of SP-deficient artificial sebum is (a) lowered by skin-extracted SP-B and (b) further reduced to a level comparable to normal sebum by the additional presence of skin-extracted SP-A and SP-D, consistent with their surface tension-lowering capabilities in lung. The possible roles of SPs in skin, based on their known functions in the lung are discussed. However, their potential as therapeutic targets or diagnostic markers of skin disease remains to be elucidated.
Mo
Young-Keun
YK
Therapeutics Research Unit, School of Medicine, University of Queensland, Princess Alexandra Hospital, Queensland, Australia.
Kankavi
Orhan
O
Masci
Paul P
PP
Mellick
George D
GD
Whitehouse
Michael W
MW
Boyle
Glen M
GM
Parsons
Peter G
PG
Roberts
Michael S
MS
Cross
Sheree E
SE
D000369:Aged, 80 and over; D002478:Cells, Cultured; D018076:DNA, Complementary / Q000378:metabolism; D005260:Female; D005333:Fetus / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007231:Infant, Newborn; D015603:Keratinocytes / Q000378:metabolism; D008297:Male; D008544:Melanocytes / Q000378:metabolism; D037662:Pulmonary Surfactant-Associated Protein A / Q000378:metabolism; D037701:Pulmonary Surfactant-Associated Protein B / Q000378:metabolism; D037721:Pulmonary Surfactant-Associated Protein C / Q000378:metabolism; D037663:Pulmonary Surfactant-Associated Protein D / Q000378:metabolism; D037661:Pulmonary Surfactant-Associated Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012629:Sebum / Q000737:chemistry / Q000187:drug effects; D012867:Skin / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D013500:Surface Tension
D018076:DNA, Complementary; D037662:Pulmonary Surfactant-Associated Protein A; D037701:Pulmonary Surfactant-Associated Protein B; D037721:Pulmonary Surfactant-Associated Protein C; D037663:Pulmonary Surfactant-Associated Protein D; D037661:Pulmonary Surfactant-Associated Proteins; D012333:RNA, Messenger; C489679:SFTPC protein, human