Objectives-To test the hypothesis of a diurnal variation in circulating levels of interleukin-6 (IL-6) and/or tumour necrosis factor-alpha (TNF-alpha) in rheumatoid arthritis and other inflammatory connective tissue diseases.

Objective-To test the hypothesis that the timing of prednisolone administration might be critical in determining its eVect on the diurnal rheumatoid inflammatory process. Methods-26 patients with rheumatoid arthritis were randomly divided into two equal groups and allocated to low doses of prednisolone at either 2.00 am or 7.30 am. Because of the diurnal variation in disease activity in rheumatoid arthritis, assessments of the two study groups were performed at 7.30 am both at the start of the study (day 1) and after four doses of prednisolone (day 5). The study protocol diVerences in the time period from the last dose of prednisolone to assessment were 5.5 hours in the 2.00 am group and 24 hours in the 7.30 am group. Results-Administration of low doses of prednisolone (5 or 7.5 mg daily) at 2.00 am had favourable eVects on the duration of morning stiVness (P << 0.001), joint pain (P < 0.001), Lansbury index (P << 0.001), Ritchie index (P << 0.001), and morning serum concentrations of IL-6 (P < 0.01). The other study group showed minor but significant eVects on morning stiVness (P < 0.05) and circulating concentrations of IL-6 (P < 0.05). Modest and similar improvements of C reactive protein, serum amyloid protein A, and erythrocyte sedimentation rate were seen in both study groups. Conclusions-Administration of low doses of glucocorticoids with a rather short biological half life seems to improve acute rheumatoid arthritis symptoms if it precedes the period of circadian flare in inflammatory activity, as defined by enhanced IL-6 synthesis. Further studies are needed to test the relative merits of diVerent timing protocols of glucocorticoid administration in rheumatoid arthritis.

SUMMARYThe aim of this work was to study the expression of b 1 -and b 2 -integrins, CR1, CD44 and Fcg receptors on peripheral blood monocytes in RA. The expression of these receptors was measured by flow cytometry, before and after treatment with low-dose prednisolone. Expression of the same receptors was also measured before and after treatment with metyrapone, a substance that inhibits the synthesis of cortisol in the adrenals. The expression of the b 2 -integrins CD11a, CD11b and CD18, of CD35 (CR1), and of FcgRII and FcgRI (CD32 and CD64) on monocytes was elevated in the RA patients compared with healthy controls, while the expression of the b 1 -integrins (CD29, CD49d, CD49f) was unaffected. A significant correlation between monocyte expression of CD64 and C-reactive protein (CRP), and blood platelet count, respectively, was found in the group of patients with RA. After 4-6 weeks of treatment with low-dose prednisolone, the expression on the monocytes of CD11a, CD11b, CD18, CD35, CD32 and CD64 was normalized. A significant correlation (r ¼ 0·64, P ¼ 0·02) was found between the decrease in expression of CD11b and clinical improvement after prednisolone treatment. Two days of metyrapone treatment, which significantly lowered the serum cortisol levels, elevated the expression of CD35 and CD49f. Priming of peripheral monocytes seems to be one of the mechanisms behind the recruitment of monocytes to the rheumatoid synovium. One reason for the good clinical effects of prednisolone in RA could be a down-regulation of adhesion and phagocytosis receptors on monocytes.

The increased serum levels of lysozyme and MPO, but not of HNL and lactoferrin in RA could indicate a stimulated secretory activity of mononuclear phagocytes. The measurement of serum lysozyme, as an indicator of monocyte/macrophage activity, might be used to study disease activity in RA.

The aim of this study was to elucidate signs of granulocyte activation by studying adhesion and phagocytosis receptors on peripheral blood granulocytes from patients with rheumatoid arthritis (RA), and to observe the effect of glucocorticoids. Analyses by flow cytometry showed elevation of the neutrophil and eosinophil expression of the α‐ and β‐chains of the β2‐integrin Mac‐1 (CD11b/CD18) and of the CEA‐gene family member 6 (CGM6, CD66b). Expression of the adhesion receptor antigens CD11a, CD29, CD49d, CD49f and CD44, and the Fcγ receptors II and III, was unaffected. Treatment with low‐dose prednisolone reduced the expression of CD11b on neutrophils and of CD11b, CD18 and CD66b on eosinophils to the same level as that found in healthy controls. Metyrapone treatment increased the surface expression of CD35 and CD49f on eosinophils, but did not affect surface expression on neutrophils. Activation of blood granulocytes may be important for the increased recruitment of neutrophils and eosinophils to the synovial cavity in RA. Treatment with low doses of glucocorticoids in RA normalizes the enhanced expression of the studied adhesion molecules in eosinophils but has minor impact on neutrophil activation. Endogenous glucocorticoid production seems to have minimal or no effect on the expression of adhesion and phagocytosis receptors on circulating granulocytes.