Am. J. Respir. Crit. Care Med., Vol 149, No. 6, Jun 1994, 1534-1538.
CD11b/CD18 expression, adherence, and chemotaxis of granulocyte in adult respiratory distress syndrome
T Laurent, M Markert, V Von Fliedner, F Feihl, MD Schaller, MC Tagan, R Chiolero and C Perret
Institut de Physiopathologie Clinique, CHUV, Lausanne, Switzerland.
The accumulation of granulocytes in the pulmonary microvasculature is
generally thought a cardinal event in the pathology of adult respiratory
distress syndrome (ARDS). However, the mechanism by which granulocytes are
sequestered in the pulmonary vascular bed remains largely unknown. Because
the CD11b/CD18 membrane receptors mediate various adhesion-dependent
functions, their expression was investigated in granulocytes from patients
during the course of ARDS development in relation to adherence and
chemotaxis. CD11b expression of ARDS resting granulocytes was increased
within 24 h of ARDS onset by a factor of two in comparison with control
patients (p < 0.05) and remained significantly increased 72 to 120 h
later. In contrast, the stimulated expression was significantly decreased
only within 24 h of ARDS onset. Adherence was not modified within 8 h of
the onset of ARDS, but was increased at Days 1, 3, and 5. The time course
of granulocyte chemotaxis shows a decreased chemotaxis capacity during the
first 3 d of ARDS, followed by normalization at Day 5. The dynamic changes
observed in the various functions studied indicate a possible relationship
between the modulation of the CD11b expression and a hyperadhesive state of
granulocytes in ARDS. These sticky granulocytes may potentially contribute
to the microvascular injury.
