Increased binding of D-penicillamine to monocytes in rheumatoid arthritis.
Long-term therapy of D-penicillamine (D-Pen) for rheumatoid arthritis (RA) is associated with a fall in rheumatoid factor, but many patients develop autoantibodies. In vitro binding of D-Pen to human peripheral blood monocytes was examined in 37 patients with RA and 75 healthy subjects. Mononuclear cells were reacted with D-Pen coupled to a fluorescein isothiocyanate-bovine serum albumin (BSA) conjugate in the presence of sodium azide and BSA, and analyzed by flow cytometry. Patients showed significantly higher D-Pen binding to monocytes than did healthy subjects. The proportion of monocytes binding D-Pen increased with age in the patients but not in healthy subjects. None of 6 patients who had D-Pen-induced autoimmune side effects was associated with increased D-Pen binding though patients with therapeutic responses showed high D-Pen binding. These results suggest that D-Pen binding to monocytes may be important in mediating therapy and inducing autoimmune side effects.
D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000188:drug therapy; D002352:Carrier Proteins / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D010396:Penicillamine / Q000009:adverse effects / Q000097:blood* / Q000627:therapeutic use; D012016:Reference Values
D002352:Carrier Proteins; D010396:Penicillamine