Use of leucocyte migration under agarose to study spontaneous and directed locomotion of leucocytes.

Three different cell attractants, together with the parallel use of the leucocyte migration agarose test (LMAT) and the leading front modification (LFM) of the Boyden chamber technique, were employed in studying whether the maximal migration of normal human polymorphonuclear leucocytes (PMNs) is higher toward an attractant (chemotaxis) than in the same attractant incorporated in the culture media (chemokinesis). Using LMAT, the maximal migration distance toward zymosan activated serum (ZAS) was found to be significantly longer than that under agarose mixed with ZAS, thus indicating a chemotactic effect exerted by ZAS. When bacterial culture filtrate (BCF) and casein were used as attractants, the corresponding difference was not significant, implying that the stimulatory effect of these substances on cell migration could be explained by increased random locomotion (chemokinesis) alone. In LFM, the migration rate was significantly higher along a casein gradient than without a gradient. Using ZAS, however, only chemokinesis could be demonstrated. BCF was found to attract PMNs into membrane filters only in the presence of human serum albumin. These observations give credence to the view that both LMAT and LFM are applicable to the in vitro assessment of chemotaxis and chemokinesis but the attractant of choice for this is different in each of the two methods.