A soluble form of CD137 (ILA/4-1BB), a member of the TNF receptor family, is released by activated lymphocytes and is detectable in sera of patients with rheumatoid arthritis.
CD137 (ILA/4-1BB) is a member of the tumor necrosis factor receptor family and regulates activation, proliferation and programmed cell death in T lymphocytes. Here we show the existence of a soluble form of CD137 (sCD137) of 16 kDa. sCD137 is released by activated lymphocytes, and in contrast to membrane-bound CD137, expression of sCD137 seems to be restricted to lymphocytes. sCD137 is generated by alternative splicing and two splice variants were identified. sCD137 is present at low levels in sera of some healthy donors (5/12; mean = 0.18 ng/ml) and is significantly enhanced in sera of patients with rheumatoid arthritis (12/12; mean = 3.58 ng/ml).
Michel
J
J
Department of Pathology, University of Regensburg, Germany.
Langstein
J
J
Hofstädter
F
F
Schwarz
H
H
D015703:Antigens, CD; D001172:Arthritis, Rheumatoid / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012326:RNA Splicing; D017475:Receptors, Nerve Growth Factor / Q000097:blood* / Q000737:chemistry / Q000235:genetics; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood* / Q000737:chemistry / Q000235:genetics; D012995:Solubility; D014407:Tumor Cells, Cultured; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9
D015703:Antigens, CD; D017475:Receptors, Nerve Growth Factor; D018124:Receptors, Tumor Necrosis Factor; C505714:TNFRSF9 protein, human; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9