The air bleb has been studied as a cavity suitable for the production of a chronic inflammatory response. The ability of carrageenan and CPPD crystals to produce a chronic response in this cavity has been studied and the nature of the reaction described quantitatively and qualitatively. Carrageenan produced a fluid exudation predominated by mononuclear cells and histologically chronic in nature. However, CPPD failed to produce an inflammatory response apart from the formation of a few foreign body giant cells. Using the model described, experiments were undertaken to examine the ability of exudates and sera taken from animals undergoing either an acute or chronic reaction to modify two models of acute inflammation. Firstly the carrageenan complement dependent pleurisy and secondly the CPPD complement independent pleurisy. Volume of chronic and acute total cell numbers were reduced by chronic and acute exudates and sera on the carrageenan pleural model. No significant effect was on the CPPD pleural model.

We studied lymphocyte subsets in the blood of twenty-four patients with alopecia areata of various degrees of severity. There was an increase in the ratio of helper to suppressor cells that correlated with the extent of the disease, providing further evidence that the immune system may be involved in its pathogenesis.

Two systems were used to test the effect of anti-inflammatory and anti-rheumatic drugs on chemotactic activity of cell-free exudates and also on the chemotactic responsiveness of exudate leucocytes. (1) Inflammatory cell-free exudates from treated rats were tested for their chemotactic activity on exudate leucocytes from untreated rats. (2) Polymorph and mononuclear cells from treated rats were tested for their responsiveness to the chemotactic activity of cell-free exudates from untreated rats. Levamisole, coumarin and D-penicillamine were ineffective in (1) and (2). Colchicine reduced chemotaxis of polymorphs in both systems (1) and (2), whereas no effect was observed on mononuclears. Naproxen was more effective in reducing the chemotaxis of polymorphs compared with mononuclears in systems (1) and (2). In contrast, indomethacin and dexamethasone reduced the chemotaxis of both polymorph and mononuclear cells in systems (1) and (21. Of the drugs tested dexamethasone exhibited the highest potency. These results emphasize the necessity for studying both cellular and humoral factors in the evaluation of the action of anti-inflammatory drugs on chemotaxis.

The accumulation of leucocytes at the site of inflammation may be brought about by chemotaxis or proliferation in the extravascular tissues. The present paper focuses on the chemotactic properties of different types of experimental inflammatory pleural exudates, using a modified Boyden chamber. The time-course of carrageenan-induced exudate chemotactic activity for polymorphs was maximal at 4 h, thereafter diminishing towards 24 and 48 h. Chemotactic activity for mononuclear cells remained unchanged throughout the 4--48 h time-course. Heating the exudates to 56 degrees C for 1 h partially reduced chemotactic activity. These results correlate well with the migration of polymorph and mononuclear cells into the pleural cavity during carrageenan-induced pleurisy. The potency of polymorph and mononuclear cell chemotactic activity of different exudates was of the following order: carrageenan greater than calcium pyrophosphate greater than reverse passive Arthus greater than dextran. The results are discussed in order to elucidate the differences between the underlying mechanisms responsible for leucocyte accumulation in different types of inflammatory reaction.

Factor Vlll-related antigen was found to be raised in diabetics, and in patients with necrobiosis lipoidica and widespread granuloma annulare who were not diabetic. It was not increased in patients with solitary lesions of granuloma annulare.The relationship of factor Vlll-related antigen to the development of micro-angiopathy in these conditions is discussed.Factor VIII is a complex of two plasma glycoproteins which are of vital importance in blood coagulation and haemostasis. It comprises factor VIII procoagulant protein (anti-haemophilic factor) and a much larger component, factor Vlll-related antigen (VIIIR Ag), which promotes haemostasis by mediating platelet aggregation and adhesion to subendothelium.