Proteome analysis identifies L1CAM/CD171 and DPP4/CD26 as novel markers of human skin mast cells.
BACKGROUND
The function of skin mast cells has been well documented in IgE-mediated allergic reactions, whereas other mast cell functions are poorly defined. This study aimed at identifying novel mast cell proteins by proteome analysis of primary human skin mast cells.


METHODS
The proteome of skin mast cells was compared to other cell types and analyzed using bioinformatics. The expression and function of two proteins hitherto not described in skin mast cells was investigated in isolated mast cells as well as in mast cells in situ.


RESULTS
Within the mast cell proteome, we identified 49 highly expressed proteins previously not described in mast cells; 21 of these proteins were found to be selectively expressed in mast cells. Two proteins, the neural cell adhesion molecule L1 and dipeptidyl peptidase 4, were further studied. L1 was found to be highly expressed in mast cells in normal, psoriasis, and mastocytosis skin. Dipeptidyl peptidase 4 was found to be expressed in mast cells in normal, psoriasis, and mastocytosis skin as well as in bone marrow mast cells in patients with systemic mastocytosis. In normal skin, mast cells were identified as a major source of dipeptidyl peptidase 4 and we also found that skin mast cells and fibroblasts secrete an active form of this enzyme.


CONCLUSIONS
In a systematic proteomics approach we identified two novel mast cell proteins potentially relevant to skin homeostasis: neural cell adhesion molecule L1 and dipeptidyl peptidase 4.
Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
M
M
Gschwandtner
Department of Dermatology, Medical University of Vienna, Vienna, Austria.
V
V
Paulitschke
Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
M
M
Mildner
Department of Dermatology, Medical University of Vienna, Vienna, Austria.
P M
PM
Brunner
Department of Plastic and Reconstructive Surgery, Medical University of Vienna, Vienna, Austria.
S
S
Hacker
Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
G
G
Eisenwort
Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
W R
WR
Sperr
Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
P
P
Valent
Institute of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria.|Institute of Cancer Research, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria.
C
C
Gerner
Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
E
E
Tschachler
D015415:Biomarkers; D019295:Computational Biology / Q000379:methods; D018819:Dipeptidyl Peptidase 4 / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D016130:Immunophenotyping; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism*; D058977:Molecular Sequence Annotation; D039842:Neural Cell Adhesion Molecule L1 / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D020543:Proteome; D040901:Proteomics / Q000379:methods; D012867:Skin / Q000166:cytology* / Q000378:metabolism
D015415:Biomarkers; D039842:Neural Cell Adhesion Molecule L1; D020543:Proteome; D018819:Dipeptidyl Peptidase 4
bone marrow; mastocytosis; proteomics; psoriasis; skin homeostasis