ABSTRACT
Doege Potter syndrome is a rare condition causing non-islet cell paraneoplastic hypoglycaemia associated with fibrous tumours, which can be both benign and malignant. The vast majority are solitary and located within the chest. Non-islet cell tumour-induced hypoglycaemia, as in Doege Potter syndrome, is quite rare and occurs around 4 times less often than islet cell-associated paraneoplastic hypoglycaemia. We present a case of Doege Potter syndrome with severe hypoglycaemia in conjunction with multiple recurrent fibrous tumours of the lung and pleura.
Subject(s)
Hypoglycemia , Kidney Diseases , Neoplasms , Congenital Abnormalities , Humans , Hypoglycemia/etiology , Kidney/abnormalities , Kidney Diseases/complications , Kidney Diseases/congenital , Neoplasms/complications , Syndrome , Urogenital AbnormalitiesABSTRACT
CD103 (αE integrin) is an important dendritic cell (DC) marker that characterizes functionally distinct DC subsets in mice and humans. However, the mechanism by which CD103 expression is regulated in human DCs and the role of CD103 for DC function are not very well understood. Here, we show that retinoic acid (RA) treatment of human monocyte-derived DCs (MoDCs) increased the ability of the DCs to synthesize RA and induced MoDC expression of CD103 and ß7 at the mRNA and protein level. In contrast, RA was unable to induce the expression of CD103 in primary human DCs isolated from the gastric mucosa. Inhibition of TGF-ß signaling in MoDCs down-regulated RA-induced CD103 expression, indicating that TGF-ß-dependent pathways contribute to the induction of CD103. Conversely, when RA-treated MoDCs were stimulated with live Helicobacter pylori, commensal bacteria, LPS, or a TLR2 agonist, the RA-induced up-regulation of CD103 and ß7 integrin expression was completely abrogated. To determine whether CD103 expression impacts DC priming of CD4+ T cells, we next investigated the ability of CD103+ and CD103â DCs to induce mucosal homing and T cell proliferation. Surprisingly, RA treatment of DCs enhanced both α4ß7 expression and proliferation in cocultured T cells, but no difference was seen between RA-treated CD103+ and CD103â DCs. In summary, our data demonstrate that RA, bacterial products, and the tissue environment all contribute to the regulation of CD103 on human DCs and that DC induction of mucosal homing in T cells is RA dependent but not CD103 dependent.
