Suppression of Natural Killer Cell Activity by Monocytes Following Immunotherapy for Recurrent Spontaneous Aborters

PROBLEM : Natural killer (NK) cell activity has previously been shown to decrease in normal pregnancy as compared with the nonpregnancy state. The purpose of this study was to determine NK cell activity in recurrent aborters and to investigate the kinetics of NK cell activity following immunotherapy. METHODS : Recurrent aborters (N = 17) were immunized with husbands' mononuclear cells (1 × 10⁸) twice during the early stage of current pregnancy. NK cell activity of recurrent aborters as well as that of normal pregnant (N = 12) and nonpregnant (N = 6) women (controls) was determined by ⁵¹Cr release assay. Monocytes were depleted from the mononuclear cell fraction and its effect on the NK cell activity was determined as well. RESULTS : At around 5 wk of gestation, NK cell activity in recurrent aborters before treatment was significantly higher (28.0 ± 5.1%) than that in normal pregnancy (18.9 ± 4.3%) (P < 0.01). Following immunotherapy, NK cell activity of recurrent aborters (N = 13) who maintained their pregnancy decreased significantly (21.7 ± 8.9%) (P < 0.05). In contrast, NK cell activity of recurrent aborters (N = 4) who aborted their current pregnancy did not decrease. Depletion of monocytes resulted in a significant increase in NK cell activity (P < 0.05). CONCLUSIONS : This study suggests that the immunotherapy induces suppression of NK cell activity which may contribute for the maintenance of pregnancy. Moreover, monocytes may be involved in this suppression.     

ROLES OF ENTEROBACTERIA, NITRIC OXIDE AND NEUTROPHIL IN PATHOGENESIS OF INDOMETHACIN-INDUCED SMALL INTESTINAL LESIONS IN RATS

Roles of enterobacteria, nitric oxide (NO) and neutrophil in indomethacin-induced small intestinal lesions were examined in rats. Indomethacin (10 mg kg-1), administered s.c. as a single injection, caused haemorrhagic lesions in the small intestine, mostly in the jejunum and ileum. The lesions were first observed 6 h after administration of indomethacin, the severity increasing progressively with time up to 24 h later. Following indomethacin, the enterobacterial numbers, inducible NO synthase (iNOS) activity and NO production in the intestinal mucosa were also increased with time, and changes in the former preceded those in the latter two as well as the occurrence of intestinal damage. Treatment of the animals with both NG-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine prevented intestinal lesions induced by indomethacin, with suppression of NO production. Both dexamethasone and FR167653 (an inhibitor of interleukin-1 beta/tumour necrosis factor-alpha production) also reduced the severity of intestinal lesions as well as the increase in iNOS activity following administration of indomethacin. Likewise, the occurrence of intestinal lesions was attenuated by pretreatment of the animals with anti-neutrophil serum (ANS). None of these treatments, however, affect the translocation of enterobacteria in the mucosa. By contrast, ampicillin (an anti-bacterial agent) suppressed the increase in mucosal iNOS activity as well as the enterobacterial numbers invaded in the mucosa and inhibited the occurrence of intestinal lesions after administration of indomethacin. These results strongly suggest that enterobacterial translocation in the mucosa is the first step required for activation of various factors such as iNOS/NO and neutrophils, all involved in the pathogenesis of indomethacin-induced intestinal lesions.     

Direct Production of the Fab Fragment Derived From the Sperm Immobilizing Antibody Using Polymerase Chain Reaction and cDNA Expression Vectors

PROBLEM : Sperm immobilizing antibodies cause infertility mainly through complement dependent sperm immobilization. To analyze any effect of sperm immobilizing antibody on fertilization, we had already established cell lines that secrete IgM monoclonal antibody (MAb H6-3C4) and IgG monoclonal antibody (MAb EnBCMGS). The latter was a class-switched recombinant IgG antibody that shares the same variable region as MAb H6-3C4. The biological effects of the IgG antibody were also reported previously to eliminate sperm immobilizing or sperm agglutinating activities. However, the method of chemical digestion of IgG had some disadvantage to prepare the purified Fab fragment stably and in large quantities. This time we report a unique method to obtain the recombinant Fab fragments (Fab EnBCMGS) using polymerase chain reaction (PCR) and cDNA expression vectors. METHOD : Two kinds of PCR primers were designed to make a truncated heavy chain (Fd) gene of MAb EnBCMGS. The amplified Fd gene and light chain gene were ligated into cDNA expression vectors and then transfected into mammalian cells. RESULTS : Expression of the Fd gene and light chain gene were confirmed by Northern blotting. Secretion of the recombinant Fab fragment from mammalian cells was also confirmed by Western blotting. The Fab fragment showed biological activity as is expected by FACS analysis. CONCLUSION : This method enables the stable production of genuine Fab fragments of IgG in mammalian cells without any chemical treatment that may be time consuming and affect the quality of the Fab fragments.     

In situ hybridization studies of stromelysin and tissue inhibitor of metalloproteinase 1 in IgA nephropathy

Summary: Accumulation of the extracellular matrix (ECM) in IgA nephropathy (IgAN) is thought to cause deterioration of glomerular function. Stromelysin and tissue inhibitor of matrix proteinase 1 (TIMP1) may play an important role in the turnover of the glomerular ECM. However, the expression of these enzymes in human renal tissues remains undefined. In the present study, non-radioactive in situ mRNA hybridization, which permitted the analysis at a cellular level, was performed to localize stromelysin and TIMP1 in renal tissue of IgAN. We also determined the percentage of cells positive for stromelysin or TIMP1 mRNA among intraglomerular cells. A total of 16 patients with IgAN were examined, including eight patients with severe histopathological changes and eight with mild changes. Three patients without glomerular disease were also studied. Stromelysin and TIMP1 mRNA were weakly expressed in the mesangium of normal kidneys and IgAN renal tissues with mild damage. However, the expression of both mRNA was significantly increased in the area of mesangial proliferation, in glomerular epithelial cells and in Bowman's capsule of advanced lesions. Several cells in the area of mesangial proliferation were double positive for stromelysin and TIMP1 mRNA, while certain cells positive for stromelysin mRNA did not express TIMP1 mRNA. In the interstitium, epithelial cells of certain tubules and some mononuclear cells were positively stained for these mRNA, especially in advanced lesions. Our results indicated that stromelysin and TIMP1 genes were expressed in glomerular resident cells, tubular epithelial cells and infiltrated mononuclear cells in IgAN, and their expression was enhanced in advanced tissue damage. the demonstration of a co-expression and discordant expression of the genes indicates that each gene expression may be regulated in a cell type-specific manner and that it could also be altered by cellular environmental factors.     

ABO blood group, other risk factors and incidence of venous thromboembolism: the Longitudinal Investigation of Thromboembolism Etiology (LITE)

Summary.  Background:  Numerous case–control studies have reported higher prevalence of non-O blood type among venous thromboembolism (VTE) patients than controls, but potential mechanisms or effect modifiers for the association are not fully established. Patients/methods:  Using a nested case–control design combining the Atherosclerosis Risk in Communities and the Cardiovascular Health Study cohort, ABO blood type and other VTE risk factors were measured on pre-event blood samples of 492 participants who subsequently developed VTE and 1008 participants who remained free of VTE. Results:  A total of 64.4% of cases and 52.5% of controls had non-O blood type. Among controls, mean values of factor VIIIc (FVIIIc) and von Willebrand factor among the non-O blood type group were higher than among the O group. Compared with O blood type, the age-adjusted odds ratio (OR) of VTE for non-O blood type was 1.64 (95% CI, 1.32–2.05) and was similar for the two parent studies and race groups. Further adjustment for sex, race, body mass index, diabetes mellitus and FVIIIc reduced the OR: 1.31 (95% CI, 1.02–1.68). Factor V Leiden (FV Leiden) appeared to modify the non-O blood type association with VTE in a supra-additive fashion, with an age-, sex- and race-adjusted OR of 6.77 (95% CI, 3.65–12.6) for having both risk factors. Conclusions:  Non-O blood type was independently associated with risk of VTE, and added to the risk associated with FV Leiden.     

Successful treatment of primary aldosteronism due to computed tomography-negative microadenoma

We report a case of aldosterone-producing microadenoma that was correctly diagnosed and thus treated less invasively by laparoscopic adrenalectomy. A 58-year-old woman presented with palpitation and muscular weakness. She exhibited hypertension, hypokalemia and increased aldosterone excretion with suppressed renin activity. Therefore, primary aldosteronism was suggested. Although adrenal scintigram and computed tomography findings in the adrenal glands were normal, adrenal venous sampling tests indicated an overproduction of aldosterone in the right adrenal gland. We diagnosed an aldosterone-producing microadenoma in the right adrenal gland and performed an adrenalectomy. The patient became normotensive postoperatively and histopathological examination demonstrated a microadenoma, 5 mm in diameter.     

Endoscopic Resection of Tumor of Papilla Vater: Our Experiences

Endoscopic papillectomy has become common in recent years as a non‐invasive therapeutic procedure for tumor of the papilla of Vater, although the lesions, which indicate endoscopic papillectomy, are very rare. In order to decide the indication for this procedure, intraductal ultrasonography (IDUS) is useful to obtain the correct diagnosis. For the successful and safe procedure of papillectomy, it is important to use the cutting mode of generator. and it is sometimes useful to inject the saline into the submucosal layer of the duodenum and to place the plastic stent into the bilio‐pancreatic ducts.     

Traumatic bladder rupture managed successfully by laparoscopic surgery

A 61-year-old man presented to our emergency department with acute abdomen. The patient had extraperitoneal and intraperitoneal traumatic bladder injury, which was successfully managed with combined endoscopic and laparoscopic procedures.