Congenital sucrase-isomaltase deficiency arising from cleavage and secretion of a mutant form of the enzyme
J. Clin. Invest. Ralf Jacob, et al. 106:281 doi:10.1172/JCI9677 [Go to this article.]

Figure 3
Ultrastructural localization of SI in biopsy specimens of CSID and a normal control. SI was localized on thin frozen sections of small bowel biopsies of the patient (a and c) and the control (b and d), which were labeled by a polyclonal antibody against SI and by 12-nm large goat anti-rabbit immunogold particles. The apical membranes (arrows) of affected enterocytes show only a weak labeling by the SI antibody, in contrast to control enterocytes. The basolateral membranes of enterocytes are free of labeling. While there is no difference in the labeling densities within Golgi stacks between patient and control enterocytes, the ER contains a slightly increased number of gold particles in affected enterocytes compared with control cells. Mi, microvilli; Lu, lumen; TJ, tight junction; BL, basolateral membrane; D, desmosome; G, Golgi apparatus; M, mitochondria. Scale bars: 0.1 μm.