LEUKOCYTE RHEOLOGICAL PROPERTIES ARE ALTERED IN PATIENTS WITH DIFFUSEATHEROSCLEROSIS

To evaluate whether atherosclerosis may be associated with altered leu cocyte rheology, we assessed leucocyte count (by Coulter counter), agg regation (by means of the leukergy test) and expression of adhesion mo lecules integrin LFA-1 and CD 44 (by means of immunofluorescence stain ing and flow cytometry) in 9 patients with carotid plus lower limb art ery atherosclerosis (group A), 14 patients with carotid atherosclerosi s only (group B) and 23 controls without atherosclerosis (group C). Th e level of LFA-1 (calculated as mean fluorescence channels MFCs) on ne utrophils, lymphocytes and monocytes was significantly higher (p <0.05 ) in group A and B patients than in controls (group A mean +/- SE : 38 3.77 +/- 9.42 vs 295.45 +/- 5.76; 474.22 +/- 8.86 vs 388.35 +/- 7.84; 457.66 +/- 12.03 vs 396.25 +/- 4.37. Group B: 322.42 +/- 6.36 vs 295.4 5 +/- 5.76; 421.42 +/- 7.21 vs 388.35 +/- 7.84; 415.71 +/- 7.73 vs 396 .25 +/- 4.37, respectively); furthermore, the MFC of LFA-1 on neutroph ils was significantly different (p <0.05) between group A and B patien ts. The percentage of aggregated leucocytes was significantly higher ( p <0.05) in group A patients (4.46 +/- 1.07) than those in groups B (1 .75 +/- 0.38) and C (1.43 +/- 0.25), whereas no significant difference was detected between groups B and C. Leucocyte number and expression of CD44 were not significantly different among the 3 groups. In conclu sion, changes in leucocyte rheology are present in patients with ather osclerosis and may contribute to chronic ischaemia.