Epstein-Barr virus-associated malignant lymphoma with macroamylasemia and monoclonal gammopathy in a patient with Wiskott-Aldrich syndrome.

A 1-year-old boy with Wiskott-Aldrich Syndrome (WAS) who developed malignant lymphoma is described. He showed various complications such as atypical lymphocytosis, disseminated intravascular coagulation (DIC), intracranial hemorrhage, macroamylasemia, and monoclonal gammopathy (immunoglobulin A kappa chain). Epstein-Barr virus (EBV) DNA was detected in the tumor tissue, and the monoclonality of B cells from the tumor tissue was established. EBV-associated lymphoma is frequently observed in immunocompromised patients including those with WAS. The development of macroamylasemia, which is rare in childhood, is discussed in relation to lymphoma and monoclonal gammopathy. This case is unique in that the EBV-associated malignant lymphoma developed at an early age and was accompanied by macroamylasemia.

Population changes in immunoglobulin-containing mononuclear cells in dextran sulfate sodium-induced coltitis.

To investigate the relation of immunoglobulin-containing cells in the colonic mucosa to mucosal inflammation, we immunohistochemically examined the localization of immunoglobulin-containing mononuclear cells in the lamina propria in dextran sulfate sodium induced colitis in mice. Mice were treated repeatedly with 3% dextran sulfate sodium (MW 54,000) solution or distilled water for a total of 170 days (chronic model), or for 85 days (subacute model) or for 10 days (acute model). IgG, IgA, and IgM-containing mononuclear cells were studied by enzyme immunostaining. The number of IgA- and IgG-containing cells gradually and significantly increased in the acute, subacute, and chronic models, in that order (P < 0.01 or 0.05). However, the numbers of IgM-containing cells in the three models were similar to that in the controls. These findings resembled those of human ulcerative colitis. In this dextran sulfate sodium-induced colitis, IgA-containing mononuclear cells may play an essential role in the mucosal immune system is the acute, subacute, and chronic phases. The finding that IgG-containing mononuclear cells increased substantially in the chronic phase suggests that IgG plays an important role in the mucosal inflammatory reaction during the chronic phase.

Changes in bacterial phagocytosis of macrophages in experimental ulcerative colitis.

We previously reported that numerous macrophages which phagocytosed dextran sulfate sodium were observed to have accumulated in the mucosal lesions and in the spleen in experimental ulcerative colitis induced in mice with dextran sulfate sodium. In this paper, we investigated the bacterial phagocytic ability of macrophages which were isolated from spleens of mice treated with 3% dextran sulfate sodium for 6 months. In this model, the number of phagocytosed bacteria (Listeria monocytogenes) and the phagocytic index were significantly decreased. The phagocytic ability of splenic macrophages obtained from nontreated mice was also evaluated by incubating with dextran sulfate sodium in vitro, and adding bacteria. The number of phagocytosed bacteria and the phagocytic index were also significantly decreased. These observations suggest that the decrease in bacterial phagocytosis in this model by macrophages that phagocytosed dextran sulfate sodium indicates a decline of the mucosal defense system to bacteria.

Bacterial invasion into the colonic mucosa in ulcerative colitis.

This study investigated interactions between mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods and cocci. In five of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the five remaining cases. It is suggested that the presence of bacteria in the colonic mucosa may be a factor responsible for the persistence or aggravation of ulcerative colitis.

Electron microscopic study of intercellular junctions in human gastric mucosa with special reference to their relationship to gastric ulcer.

The development of gap junctions in the human gastric mucosa has been examined to see if there is any relation to gastric ulcer. Freeze fracture replicas were prepared from the endoscopic biopsy specimens of 20 patients with gastric ulcer (15 men and five women, aged 49 (13) years) and seven healthy volunteers (four men and three women, aged 41 (19) years). Large fractured areas of lateral cell membranes of surface mucous cells were observed randomly at a direct magnification of 15,000 using electron microscopy. Small gap junctions were observed between gastric surface mucous cells in all healthy volunteers. Gap junctions in the patients with gastric ulcer were significantly fewer than in the healthy volunteers. In addition, gap junctions in patients with recurrent ulcer were significantly fewer than in those with first onset ulcer. There was no obvious relationship between age and the development of gap junctions in patients with gastric ulcer or in healthy volunteers. In areas of intestinal metaplasia, gap junctions were occasionally seen between absorptive cells of the villi, but not in the lateral membranes of goblet cells. These findings suggest that loss of intercellular communication via gap junctions is associated with gastric ulcer formation.