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We report a rare case of intrahepatic cholangiocarcinoma (IHCC) arising many years after excision of a type IV-A congenital choledochal cyst. A 44-year-old man was transferred to our hospital with acute cholangitis more than 34 years after several operations for congenital biliary dilatation. Imaging showed a huge tumor in the left medial section of the liver, extending to the porta hepatis. Although he had no jaundice, the intrahepatic bile ducts showed cylinder-like dilatation with narrowing of the hilar bile duct. At surgery, the tumor was found to arise from the dilated intrahepatic bile duct just above the narrow portion. He underwent a left hepatic trisectionectomy with a vascular procedure. Microscopically, the tumor was confirmed to be moderate-to-well-differentiated tubular adenocarcinoma. Thus, when the narrow segment is left untouched, careful long-term follow-up is important to detect new lesions at an early stage.

Recent studies in mice have revealed that a newly observed population of T cells which coexpresses an NK marker, NK1·1 (i.e. natural killer T or NKT cells) recognizes some glycolipid antigens as well as peptide antigens in the context of a monomorphic MHC class I-like antigen (i.e. CD1d) [1][2][3][4][5]. These NKT cells use an invariant Va14 chain for TCRa and Vb8, Vb2, and Vb7 chains for TCRb [6][7][8]. A similar population of T cells has been characterized even in humans [9,10]. In murine studies, it has been proposed that NKT cells are immunoregulatory T cells for the suppression of autoimmune diseases. This proposal was based on the fact that autoimmune mice such as MRL-lpr/lpr [11,12] and NOD mice [13][14][15] showed a decreased level of NKT cells. However, subsequent studies have raised another possibility, namely, that NKT cells mediate autoreactivity against self-cells when they are activated with or a-galactosylceramide (a-GalCer) [17].In light of these findings, we herein examined whether denatured self-antigens induce the expansion of NKT cells and the production of autoantibodies. Since NKT cells are abundant in the liver [18][19][20], we injected denatured liver tissue into mice. This idea arose from findings that the number of NKT cells in the liver increased after partial hepatectomy [21]. At such time, damaged hepatocytes and regenerated hepatocytes seemed to stimulate the expansion of NKT cells in the liver. As expected, the injection of denatured liver tissue stimulated NKT cells in the liver. Interestingly, liver damage and autoantibody production were accompanied by the expansion of NKT cells. The possible association of NKT cells and certain B cells (e.g. B-1 cells) with the onset of autoimmune diseases is herein discussed.There has been a question as to the causes of the onset of autoimmune diseases [1]: Does the genetic background which induces abnormal immune functions permit the generation of autoreactive lymphocytes, resulting in the induction of autoimmune diseases? and [2] Does tissue damage (leaked self-antigens) which is evoked by viral infection or other inflammations stimulate the expansion of autoreactive lymphocytes and induce autoimmune diseases? Although we have to consider both possibilities, we propose the latter possibility in this study. 397 Simultaneous activation of natural killer T cells and autoantibody production in SUMMARYDenatured syngeneic liver tissue prepared by mechanical procedures was intraperitoneally injected into adult C57BL/6 mice. In parallel with a decrease in the total number of lymphocytes in the liver, spleen, and thymus from days 1-7 after the injection, the proportion of the CD4 + NK1·1 + CD3 int subset of these cells (i.e. natural killer T or NKT cells) increased in the liver. Even the absolute number of these NKT cells increased in the liver on days 14 and 21. In response to the injection of denatured liver tissue, tissue damage was induced in the liver, as shown by elevated levels of serum transaminases and hepatocyte degeneration observed by e...

SUMMARYGiven that there are few natural killer T (NKT) cells in the liver of athymic nude mice and in neonatally thymectomized mice, it is still controversial whether all NKT cells existing in the liver are supplied by the thymus or if some such cells develop in the liver. To determine whether or not NKT cells are consistently supplied from the thymus during adult life, thymectomy was conducted in mice at the age of 8 weeks. Interestingly, the proportion and number of CD4 + NKT cells increased or remained unchanged in the liver after adult thymectomy and this phenomenon continued for up to 6 months after thymectomy. The administration of a-galactosylceramide induced severe cytopenia (due to apoptosis) of CD4 + NKT cells in the liver on day 1, but subsequent expansion of these NKT cells occurred in thymectomized mice similar to the case in normal mice. However, in thymectomized mice given lethal irradiation (9 . 5 Gy) and subsequent bone marrow transfer, the population of CD4 + NKT cells no longer expanded in the liver, although that of CD8 + NKT cells did. These results suggest that thymic CD4 + NKT cells, or their progenitors, may migrate to the liver at a neonatal stage but are not supplied from the thymus in the adult stage under usual conditions. CD8+ NKT cells can be generated in the liver.

Restorative proctocolectomy with ileal pouch anal anastomosis (IPAA) has become the standard surgical procedure for ulcerative colitis (UC). The purpose of this study was to determine which factors are important to achieve good anal continence after IPAA in terms of the motor activity and pressure-volume relationship. A total of 17 patients with UC who underwent IPAA were evaluated. The internal ileal pouch pressure was transanally measured with and without volume-loading of the pouch which induces the urge to evacuate. The maximum tolerable volume (MTV), first urge volume (FUV), and ileal pouch compliance were calculated and the internal ileal pouch pressure records were subjected to spectral analysis for intensive evaluation of the intraluminal pressure waves. The FUV, correlation of the compliance of the FUV with MTV, and the remaining volume up to the MTV (RVMTV) were analyzed. Compliance of the FUV was significantly correlated with the RVMTV (r = 0.736, P< 0.01). The frequency of the phasic waves in the pouch decreased with length of follow up, reflecting improved function (r = -0.588, P < 0.05). The findings of this intensive analysis of manometric measurement indicate that the key factors in postoperative pouch function are RVMTV and the frequency of phasic waves in the W-pouch.