Identification of secreted CD155 isoforms.
The CD155 gene is a member of the immunoglobulin superfamily. We first demonstrate the existence of soluble CD155 (sCD155) isoforms in culture medium conditioned by CD155-expressing cells, in human serum and in cerebrospinal fluid. sCD155 concentration was measured in human serum and cerebrospinal fluid using a specific ELISA. Analysis of conditioned media indicated that sCD155 release does not require protease activity. In order to determine which tissues are responsible for sCD155 expression, we have quantified CD155 mRNAs in human normal tissues. The highest expression was observed in liver. The CD155alpha transcript is the most abundant and the proportion of the CD155beta and CD155gamma variants was similar between the tissues. Finally, serum purified sCD155 reduces poliovirus entry mediated by membrane-bound CD155. The high level of CD155 synthesis in many tissues and the presence of sCD155 in biological fluids suggest the existence of an important role for the protein in cellular function.
Baury
Béatrice
B
Institut National de la Santé et de la Recherche Médicale U539, Faculté de Médecine, 1 rue Gaston Veil, 44035 Nantes, France.
Masson
Damien
D
McDermott
Brian M
BM
Jarry
Anne
A
Blottière
Hervé M
HM
Blanchardie
Philippe
P
Laboisse
Christian L
CL
Lustenberger
Patrick
P
Racaniello
Vincent R
VR
Denis
Marc G
MG
D015153:Blotting, Western; D002555:Cerebrospinal Fluid / Q000378:metabolism; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008099:Liver / Q000378:metabolism; D008565:Membrane Proteins; D010957:Plasmids / Q000378:metabolism; D017955:Poliovirus / Q000378:metabolism; D020033:Protein Isoforms; D017434:Protein Structure, Tertiary; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism; D011991:Receptors, Virus / Q000096:biosynthesis / Q000737:chemistry*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured
D017077:Culture Media, Conditioned; D008565:Membrane Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D011991:Receptors, Virus; C066100:poliovirus receptor