ITGAL and pulmonary arterial hypertension: As shown in fig 1A, PB T cells expressing LFA-1 were significantly higher in patients with SSc-PAH at baseline (mean (SD) 46.3 (6)%) than in HD (32.6 (3)%, p<0.05) or in patients with SSc without PAH (35.8 (5)%, p<0.05).