METABOLIC DEVIATIONS OF POLYMORPHONUCLEAR LEUKOCYTES IN RHEUMATOID ARTHRITIS

Polymorphonuclear leukocytes of normal individuals and of patients with rheumatoid arthritis were incubated in serum containing14C-labeled propionic acid. The overall metabolism was studied by determination of radioactivity in the respiratory CO2, lipids, proteins, amino acids and lactate. The metabolism of polymorphonuclear leukocytes of the arthritic group differed from that of normal individuals in the following respects. They converted less14C-propionic acid into metabolic products, particularly CO2 and protein. Leukocytes of normal subjects convert14C-propionate into aspartic acid and glutamic acid, while leukocytes of patients with rheumatoid arthritis also convert propionate into β-alanine. It appears that polymorphonuclear leukocytes of patients with rheumatoid arthritis and of normal individuals possess a Krebs cycle. Leukocytes of the arthritic group and of normal subjects show a similar14C-distribution pattern in the lactate when incubated 2-14C-propionate. It is concluded that the formation of lactic acid from 2-14C-propionate may proceed to a small extent by an alternate pathway (acrylyl-CoA). The identification of labeled β-alanine was found only in the arthritic group and may be unique for rheumatoid arthritis. © 1969 J. F. Lehmanns Verlag.