Fig. 4

(panels 4-I; 4-II): Pathologic aorta studies performed in 8 patients (5 from group-1 and 3 from group-2) diagnosed with aortic dissection involving the ascending, thoracic and abdominal aorta, as were described in three medical centers in the north of Israel. In brief, “cystic medial degeneration and necrosis” was the main common pathological finding reported in all patients. This was accompanied with more details such like “focal fibrin deposits admixed with neutrophils with signs of cystic medial necrosis” “adventitial and periadventitial fibrosis”. Here, we compare between normal and affected aorta sections from patient VI-27, VII-1 and V-22 (Fig. 1) by using different aorta staining. First, a reprehensive Elastica – van Gieson staining presented in the upper panels (4-I): a and c (for normal aorta) showing the regular layered pattern of elastic tissue as expected in normal media, this was compared with affected aorta samples (panels b and d patient VI-27) showing disruption and fragmentation of elastic lamellae of the aortic media with formation areas devoid of elastin (asterisk) that resemble cystic spaces. Lower panels (4-II) show MLKC staining Immunohistochemistry. We used primary antibody directed against human MLCK in all aortic sections obtained from normal and three patients namely VI-27, VII-1 and V-22 (Fig. 1). The panels represent staining of normal aorta section (normal) where the MLCK protein is stained brown (encircled) compared with aorta staining in three patients’ sections. The MLCK is not detected in patients VI-27, VII-1 (both found homozygous to the Ala1491Ser mutation) while, it is weak but diffuse in patient V-22 (heterozygous for Ala1491Ser mutation)