Enhanced ability of regulatory T cells in chronic hepatitis C patients with persistently normal alanine aminotransferase levels than those with active hepatitis.

In hepatitis C virus (HCV) infection, the Th1-type immune response is involved in liver injury. A predominance of immunosuppressive regulatory T cells (Treg) is hypothesized in patients with persistently normal alanine aminotransferase (PNALT). Our aim was to clarify the role of Treg in the pathogenesis of PNALT. Fifteen chronically HCV-infected patients with PNALT, 21 with elevated ALT (CH) and 19 healthy subjects (HS) were enrolled. We determined naturally-occurring Treg (N-Treg) as CD4+CD25high+FOXP3+ T cells. The expression of FOXP3 and CTLA4 in CD4+CD25high+ cells was quantified by real-time reverse transcriptase-polymerase chain reaction. Bulk or CD25-depleted CD4+ T cells cultured with HCV-NS5 loaded dendritic cells were assayed for their proliferation and cytokine release. We examined CD127-CD25-FOXP3+ cells as distinct subsets other than CD25+ N-Treg. The frequencies of N-Treg in patients were significantly higher than those in HS. The FOXP3 and CTLA4 transcripts were higher in PNALT than those in CH. The depletion of CD25+ cells enhanced HCV-specific T cell responses, showing that co-existing CD25+ cells are suppressive. Such inhibitory capacity was more potent in PNALT. The frequency of CD4+CD127-CD25-FOXP3+ cells was higher in CH than those in PNALT. Treg are more abundant in HCV-infected patients, and their suppressor ability is more potent in patients with PNALT than in those with active hepatitis.

Effect of linoleic acid hydroperoxide on production of matrix metalloproteinases by human aortic endothelial and smooth muscle cells.

The effect of linoleic acid hydroperoxide on the production of proforms of matrix metalloproteinase-1, -2, and -3 (proMMP-1, -2, and -3) in cultured human arterial endothelial and smooth muscle cells was investigated. Upon cultivation of the endothelial cells in the absence of the hydroperoxide, only proMMP-1 was detected, and its amount was increased by cultivation with the hydroperoxide. In the cultures of the intimal smooth muscle cells in the absence of the hydroperoxide, a large amount of proMMP-2 and small amounts of proMMP-1 and -3 were detected, and the hydroperoxide treatment increased remarkably the amounts of proMMP-1 and -3, but rather decreased the amount of proMMP-2. In the cultures of the medial smooth muscle cells, the same tendency was observed. However, the amounts of these proenzymes found in the intimal smooth muscle cells exceeded those found in the medial smooth muscle cells, both in the absence and in the presence of the hydroperoxide. Possible involvement of these phenomena in atherogenesis was discussed.

Induction of gelatinolytic neutral proteinase secretion by lipid peroxide in cultured mesangial cells.

To investigate whether lipid peroxides in tissue and/or blood play an important role in the injury to mesangial cells and glomerular structural proteins, we studied the effect of linoleic acid hydroperoxide (LHO) on mesangial cells cultured from rat kidneys. When 1.0-3.0 nmol/ml of LHO were added to the culture, the production of 70-kDa gelatinolytic neutral proteinase by mesangial cells was enhanced without morphological damage. The production of the enzyme, however, was inhibited by an addition of 4.0 or 5.0 nmol/ml of LHO and a microscopic examination also demonstrated marked injury to mesangial cells in the presence of these concentrations of LHO. These data suggest that there is a possibility that increased lipid peroxides in tissue and/or blood play a role in the injury to mesangial cells and glomerular structural proteins leading to mesangiopathy.

Immortalization of human aortic smooth muscle cells with origin-minus simian virus 40 DNA.

We established two cell lines of human smooth muscle cells (SMC) by transfection of cells from the aortic intima and aortic media with origin-minus simian virus 40 (ori-minus SV40) DNA. Ori-minus SV40 DNA very efficiently immortalized human smooth muscle cells in culture. Proteins that these cell lines produced included type I, III, IV, and V collagens, fibronectin, and human matrix metalloproteinases (MMP)-1 (tissue collagenase), -2 ("type IV collagenase"), and -3 (stromelysin). The protein production in these cell lines generally mimicked that of normal SMC, but the immortalization stimulated the cell line of medial SMC to produce excessive MMP-2 and to secrete MMP-9 (92-kDa gelatinase). However, since these cell lines did not show a fully malignant phenotype, we concluded that, in addition to the degradation of extracellular matrix macromolecules, including basement membrane components by MMP-2, -3, and/or -9, some additional factors must be involved for the malignancy of fully transformed cells and that these immortalized human aortic SMC, which share many characteristics with normal SMC, will prove useful to study the role(s) of metalloproteinases in atherosclerosis.

[Pancreas head carcinoma associated with situs inversus viscerum totalis].

The patient was a seventy seven years old male whose chief complaint was jaundice. Chest and abdomen roentgenogram showed situs inversus viscerum totalis. Echographically, pancreas head tumor was showed. Stenosis of inferior bile duct and dilatation of main pancreatic duct were showed by percutaneous transhepatic cholangiography and endoscopic retrograde cholangio pancreaticography. So, pancreas head carcinoma associated with situs inversus viscerum totalis was diagnosed. Pancreaticoduodenectomy and modified Child method was undergone. At the time of operation, liver was recognized left side of abdomen. The tumor was diagnosed well or moderately differentiated papillotubular adenocarcinoma by pathological study. This unusual combination of situs inversus viscerum totalis and pancreas head carcinoma was reported.