Monocytes accumulate on Rebuck skin window coverslips but not in skin chamber fluid. A comparative evaluation of two in vivo migration models.

Migration of leukocytes into an inflammatory site is an important step of host defense. The Rebuck skin window and the skin blister chamber technique allow study of the dynamics of the inflammation in vivo. The type of inflammation is basically different in each of these methods. Whereas the former technique provokes a late monocytic response, the latter technique provokes virtually no monocyte accumulation. the difference between these two types of inflammation has never been systematically studied. We describe a skin blister chamber technique with a novel multiwell device which allows the observation of cell accumulation under different conditions, i.e., in presence and in absence of a foreign body (coverslip). This method proved simple and reproducible with variability among volunteers exceeding variability of replicate chambers within a given subject. Furthermore, it confirms that no monocytes accumulate in blister chambers during the first 20 h of inflammation, whereas monocytes accumulate on skin window coverslips within the first 6 h of inflammation. Control experiments show that the continuous presence of the coverslip in the skin window is the critical element provoking accumulation of monocytes. A different degree of neutrophil degranulation in presence and absence, respectively, of a foreign body may be responsible for the different types of inflammatory response.