Expression of L-selectin, CD43, and CD44 in synovial fluid neutrophils from patients with inflammatory joint diseases. Evidence for a soluble form of L-selectin in synovial fluid.
OBJECTIVE
To study the expression of L-selectin, CD43, and CD44 on peripheral blood (PB) and synovial fluid (SF) neutrophils from patients with inflammatory joint diseases, and to investigate the presence of soluble L-selectin in both SF and plasma from patients with acute and chronic arthritis.


METHODS
PB and SF neutrophils were isolated from 13 patients with rheumatoid arthritis (RA) and 17 patients with various inflammatory joint diseases other than RA. Expression of L-selectin, CD43, CD44, CD11a, and CD11b was determined in both unstimulated and in vitro-activated cells by immunofluorescence flow cytometry. Soluble L-selectin levels were estimated in SF and plasma by a semiquantitative radioimmunoassay.


RESULTS
Neutrophils from SF showed diminished expression of L-selectin compared with PB neutrophils; CD43 expression and CD44 expression were decreased in SF neutrophils from most patients. In contrast, SF neutrophils exhibited significantly increased expression of CD11b, to an extent similar to that seen with in vitro-activated PB neutrophils. Soluble L-selectin was detected at similar levels in SF and PB.


CONCLUSIONS
The phenotypic profile of SF neutrophils (low levels of L-selectin, CD43, and CD44, and high levels of CD11b) from most patients with RA or other inflammatory joint conditions resembles that observed in in vitro-activated neutrophils. Our results suggest that SF neutrophils are activated to a similar degree in inflammatory joint diseases with different pathogenic mechanisms.
Humbría
A
A
Section of Rheumatology, Hospital de la Princesa, Madrid, Spain.
Díaz-González
F
F
Campanero
M R
MR
Arroyo
A G
AG
Laffón
A
A
González-Amaro
R
R
Sánchez-Madrid
F
F
D000208:Acute Disease; D015703:Antigens, CD; D001168:Arthritis / Q000097:blood / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology; D002352:Carrier Proteins / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000097:blood / Q000378:metabolism*; D002908:Chronic Disease; D006801:Humans; D018960:Hyaluronan Receptors; D019041:L-Selectin; D051917:Leukosialin; D016177:Macrophage-1 Antigen / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism*; D012795:Sialoglycoproteins / Q000378:metabolism*; D012995:Solubility; D013582:Synovial Fluid / Q000166:cytology / Q000276:immunology*
D015703:Antigens, CD; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D018960:Hyaluronan Receptors; D051917:Leukosialin; D016177:Macrophage-1 Antigen; D011956:Receptors, Cell Surface; D016201:Receptors, Lymphocyte Homing; C465014:SPN protein, human; D012795:Sialoglycoproteins; D019041:L-Selectin