Immunohistochemical changes in synovial tissue during the course of adjuvant arthritis.
OBJECTIVE
To study immunohistochemical changes occurring in knee synovial membranes of rats during the time course of adjuvant arthritis (AA). The effect of treatment with dexamethasone after establishment of arthritis was also studied.


METHODS
AA was induced in Wistar rats by means of a single injection of a suspension of Mycobacterium butyricum. On Days 7, 14, 17, 21, 28 and 42 after induction, synovial membranes were obtained, frozen and sectioned on a cryostat. Tissue sections were tested by peroxidase-antiperoxidase method, using the following monoclonal antibodies: OX19 (CD5), W3/25 (CD4), OX8 (CD8), OX6 (Ia), OX33 (LCA) and OX39 (CD25).


RESULTS
Knee synovial membranes obtained from arthritic rats on days of maximum inflammation showed few or no CD5+ cells, a higher proportion of CD8+ cells, and a higher number of CD4+ and Ia+ cells than healthy synovial tissues. CD25+ cells were observed from Day 7 postinduction and remained numerous throughout the study.


CONCLUSIONS
Few T lymphocytes (CD5+) were found in arthritic synovial membrane, whereas an increase of cells expressing CD8, CD4, CD25, Ia, and LCA was found. These increases (except CD8) are not evident in dexamethasone treated rats.
Pelegrí
C
C
Unit of Physiology, Faculty of Pharmacy, University of Barcelona, Spain.
Franch
A
A
Castellote
C
C
Castell
M
M
D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D001169:Arthritis, Experimental / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D015704:CD4 Antigens / Q000032:analysis; D018956:CD5 Antigens; D016827:CD8 Antigens / Q000032:analysis; D003907:Dexamethasone / Q000627:therapeutic use; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007150:Immunohistochemistry; D007719:Knee Joint / Q000276:immunology / Q000473:pathology; D017493:Leukocyte Common Antigens / Q000032:analysis; D009161:Mycobacterium / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013583:Synovial Membrane / Q000378:metabolism / Q000473:pathology*; D013585:Synovitis / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology
D015703:Antigens, CD; D015704:CD4 Antigens; D018956:CD5 Antigens; D016827:CD8 Antigens; D000949:Histocompatibility Antigens Class II; D015375:Receptors, Interleukin-2; D003907:Dexamethasone; D017493:Leukocyte Common Antigens