and myofibroblasts appear to be independent nonparenchymal cells within the liver. That both cell types are present in normal liver also argues in favor of a dual population. Furthermore, a clear immunohistochemical distinction between the two is maintained during prolonged culture, a state which may be analogous to activation in uivo. Does this study, then, refute the notion that FSC transform into myofibroblasts? Viewing the entire population of FSC as a whole, it does not seem that they are predisposed to this particular alteration. Some cells are capable of modifying their intermediate filament profile, however, as in the case of aortic smooth muscle in the present study. Thus, in the presence of an appropriate stimulus, transformation of at least a subpopulation of FSC into myofibroblasts cannot be excluded.
At present, there is no specific histological marker to designate myofibroblasts. Classifying them as separate from FSC, in essence by default, as is the case with desmin, is less than optimal. Comparing the two cell types in culture also has its disadvantages, because of phenotypic modulation which may obscure any differ-
THE INITIAL HEMORRHAGE FROM ESOPHAGEAL VARICES
Ttici North Italian Endoscopic C'lub for the Study and Treatment of Esophageal Varices. Prediction of the first variceal hemorrhage in patients with cirrhosis of the liver and esophageal varices. N Engl ,