Lack of antibody production against Hanganutziu-Deicher (H-D) antigens with N-glycolylneuraminic acid in patients with porcine exposure history

The significance of non-alphagalactosyl antigens remains unclear in pig-to-primate xenotransplantation. Hanganutziu-Deicher (H-D) antigens with terminal N-glycolylneuraminic acid (NeuGc) are widely expressed on endothelial cells of mammalian species, with the exception of humans. As baboons and monkeys also express H-D antigens, a pig-to-non-human primate experimental model cannot resolve the question of whether H-D antigens can elicit a potent humoral response in human recipients. The purpose of this study was to elucidate the clinical significance of H-D antigens by examining the sera from patients who have been previously exposed to porcine tissue. After the digestion of porcine aortic endothelial cells (PAEC) by neuraminidase, NeuGc and N-acetylneuraminic acid (NeuAc) were quantitated by HPLC. IgG and IgM antibody levels against H-D antigens were measured by NeuGc-GM3-coated ELISA plates in the sera of patients who had undergone ex vivo kidney perfusion 1 to 3 weeks and 2 years previously (n=2) or had been injected with fetal porcine islets 2 months previously (n= 10). HPLC determined that 9.7x 10(7) NeuAc and 6.3x 10(7) NeuGc residues per cell were released from PAEC by neuraminidase, while 25.7x 10(7) NeuAc and an undetectable level of NeuGc were released from human aortic endothelial cells (HAEC). No significant elevation of IgG or IgM antibody levels against NeuGc-GM3 was observed in sera from patients with a history of porcine exposure. Considering the active production of antibody against the foreign galactosyl antigens after pig-to-human xenotransplantation, some production of antibodies against the equally foreign H-D antigens would be expected, because large amounts of NeuGc terminated saccharides are present in the pig endothelial cell surface. However, no production of antibodies directed to H-D antigens could be found in patients exposed to porcine tissue. Further studies are warranted to explain why H-D antigens do not elicit a significant antibody production.

Generalized peritonitis due to spontaneously perforated pyometra presenting as pneumoperitoneum: report of a case

We report a rare case of generalized peritonitis due to a ruptured pyometra in an 86-year-old woman, and also conduct a review of the previous Japanese literature. The patient presented with muscle guarding and rebound tenderness. Computed tomography (CT) disclosed a cystic mass in the peritoneal cavity, in which an air-fluid level was noted. Pneumoperitoneum around the uterus due to gas production of anaerobic bacteria was noted on a CT. At laparotomy, the uterus was markedly enlarged with a necrotic area on the uterine fundus, which was found to be perforated. A supravaginal hysterectomy and drainage were performed. We found only eight cases of a ruptured pyometra presenting as pneumoperitoneum in the Japanese literature between 1977 and 1999. The most common cause of pneumoperitoneum is a perforation of the gastrointestinal tract. However, other possible causes, as seen in our patient, should also be taken into consideration. Although it is rare, a perforated pyometra should therefore also be considered when elderly women present with acute abdominal pain.

Blockade of transforming growth factor beta/Smad signaling in T cells by overexpression of Smad7 enhances antigen-induced airway inflammation and airway reactivity

Transforming growth factor (TGF)-beta has been implicated in immunosuppression. However, it remains obscure whether regulation of T cells by TGF-beta contributes to the immunosuppression in vivo. To address this issue, we developed transgenic mice expressing Smad7, an intracellular antagonist of TGF-beta/Smad signaling, selectively in mature T cells using a plasmid construct coding a promoter element (the distal lck promoter) that directs high expression in peripheral T cells. Peripheral T cells were not growth inhibited by TGF-beta in Smad7 transgenic mice. Although Smad7 transgenic mice did not spontaneously show a specific phenotype, antigen-induced airway inflammation and airway reactivity were enhanced in Smad7 transgenic mice associated with high production of both T helper cell type 1 (Th1) and Th2 cytokines. Thus, blockade of TGF-beta/Smad signaling in mature T cells by expression of Smad7 enhanced airway inflammation and airway reactivity, suggesting that regulation of T cells by TGF-beta was crucial for negative regulation of the inflammatory (immune) response. Our findings also implicated TGF-beta/Smad signaling in mature T cells as a regulatory component of allergic asthma.

Expression levels of thymidine phosphorylase and dihydropyrimidine dehydrogenase in various human tumor tissues

Thymidine phosphorylase (dThdPase) is the rate-limiting enzyme that metabolizes 5'-deoxy-5-fluorouridine (5'-dFUrd, doxifluridine), an intermediate metabolite of capecitabine, to the active drug 5-fluorouracil (5-FUra), while dihydropyrimidine dehydrogenase (DPD) catabolizes 5-FUra to an inactive molecule. The susceptibility of tumors to fluoropyrimidines is reported to correlate with tumor levels of these enzymes. To obtain some insight into the tumor types susceptible to fluoropyrimidine therapy, we measured expression levels of these two enzymes in various types of human cancer tissues (241 tissue samples) by the ELISA methods. DPD exists in all the cancer types studied, such as bladder, breast, cervical, colorectal, esophageal, gastric, hepatic, pancreatic, prostate, and renal cancers. Among them, the cervical, hepatic, pancreatic, esophageal, and breast cancer tissues expressed high levels of DPD (median >70 U/mg protein), while high concentrations of the dThdPase were expressed in esophageal, cervical, breast, and pancreatic cancers and hepatoma (median >150 U/mg protein). The dThdPase/DPD ratio, which was reported to correlate with the susceptibility of human cancer xenografts to capecitabine, was high in esophageal, renal, breast, colorectal, and gastric cancers (median ratio of >1.5). In any of these three parameters, the inter-patient DPD variability for each cancer type was much larger than the DPD variability among cancer types; highest/lowest ratios for dThdPase, DPD, and dThdPase/DPD were 10-321, 7-513, and 2-293, respectively. These results indicate that measurements of the three parameters, DPD, dThdPase and dThdPase/DPD, would be useful criteria for selecting cancer patients suitable for fluoropyrimidine therapy rather than for selecting cancer types.

The prognosis of intraductal papillary mucinous tumors of the pancreas

BACKGROUND/AIMS

Intraductal papillary mucinous tumors of the pancreas have been recognized as a distinct clinical entity. However, their biological behavior has not been clearly defined. The aim of this study was to examine the prognosis of this tumor, to clarify the biological behavior and determine the most appropriate treatment.

METHODOLOGY

Correlations between prognosis of operated cases and histopathologic features were investigated.

RESULTS

In 105 patients with characteristic clinical features of intraductal papillary mucinous tumors, the lesions were classified as hyperplasias in 21%, intraductal tumors in 48% and invasive carcinomas in 31%. Minimal invasion was apparent in 25%, lymph node metastasis in 21%, and fistula formation in 31% of the invasive lesions. Non-invasive and minimally invasive intraductal papillary mucinous tumors were essentially free from risk of tumor recurrence. Other invasive intraductal papillary mucinous tumors showed a significantly poor prognosis.

CONCLUSIONS

Because of the variation in pathological characteristics, patient outcome and the possibility of differential diagnosis, the treatment might be recommended as follows: the case of hyperplasia can be followed-up with close surveillance. Non-invasive and minimally invasive intraductal papillary mucinous tumors should be operated with function-preserving minimal pancreatectomy. For patients with invasive intraductal papillary mucinous tumors evident with preoperative imaging modalities, radical operations with lymph node dissection might be needed.

Significance of transporter associated with antigen processing gene polymorphism in living related renal transplantation

The HLA class I and class II mediated antigen presentation plays a major role in the initiation of immune response and the development of acute rejection after transplantation. The purpose of this study was to examine whether MHC-encoded antigen processing (TAP1, TAP2, LMP2, DMA and DMB) gene polymorphisms were associated with the incidence and the severity of acute rejection after renal transplantation. We studied a selected population of 112 pairs of donors and recipients who underwent living-related renal transplantation. They were divided into 3 groups: rejection-free (Group A, n = 51), steroid-sensitive rejection (Group B, n = 31) and steroid-resistant rejection (Group C, n = 30). The frequency of TAP2*0103 (41.2%) was significantly higher in the donors of Group A than that of Group B (12.9%, p = 0.0070, pc = 0.0280) or Group C (16. 7%, p = 0.0225, pc = 0.0900). No significant difference was observed in the allelic frequencies of the TAP1, LMP2, DMA, and DMB genes in the donors or recipients among Groups A, B, and C. This result supported the idea that the TAP2 gene polymorphism might be functionally related to antigen presentation. It also suggested that donor's antigen presenting cells with the TAP2*0103 allele would have the attenuated efficacy in the presentation of allospecific antigens to recipient's T cells.

Combined effects of adeno-associated virus vector and a herpes simplex virus mutant as neoplastic therapy

BACKGROUND AND OBJECTIVES

Although surgical therapy for pancreatic cancer has not been successful, new gene therapies, such as adeno-associated virus (AAV) vectors hold promise for treating cancer. However, expression of AAV vectors alone is insufficient for adequate effects in vivo for cancer therapy. We describe a novel therapy using the combined herpes simplex virus-ICP6 deletion mutant (ICP6delta) and AAV vector.

METHODS

We investigated ICP6delta and AAV regarding kinetics and dose-response relationships of LacZ expression in vitro. We studied the expression of LacZ in vivo using subcutaneous pancreatic cancer tumors (SW1990) in nude mice.

RESULTS

In vitro, ICP6delta enhanced the expression of AAV; 24 hr following inoculation there was more expression with AAV plus ICP6delta than with AAV plus KOS, and a multiplicity of infection (MOI) of 0.5 was the optimal titer of ICP6delta to support maximal expression of AAV. In vivo, there was much higher expression of LacZ in mice injected with AAV-LacZ plus ICP6A than with AAV-LacZ alone.

CONCLUSIONS

ICP6delta enhances expression of AAV-vector in vitro and in vivo. These results suggested that combined therapy have potential for human cancer.

Molecular cloning of endo-beta -galactosidase C and its application in removing alpha -galactosyl xenoantigen from blood vessels in the pig kidney

Galalpha1-3Gal is the major xenoantigenic epitope responsible for hyperacute rejection upon pig to human xenotransplantation. Endo-beta-galactosidase C from Clostridium perfringens destroys the antigenic epitope by cleaving the beta-galactosidic linkage in the Galalpha1-3Galbeta1-4GlcNAc structure. Based on partial peptide sequences of the enzyme, we molecularly cloned the enzyme gene, which encodes a protein with a predicted molecular mass of about 93 kDa. The deduced protein sequence of the enzyme has limited homology in the C-terminal half with endo-beta-galactosidase from Flavobacterium keratolyticus and beta-1,3-glucanases. The enzyme expressed in Escherichia coli removed the alpha-galactosyl epitope nearly completely from pig erythrocytes and from pig aortic endothelial cells. The enzyme-treated endothelial cells in culture were greatly reduced in cell surface antigens, which were recognized by IgM, IgG, or IgA in human sera, and became much less susceptible to complement-mediated cytotoxicity caused by human sera. When the pig kidney was perfused with the enzyme, the vascular endothelial cells became virtually devoid of the alpha-galactosyl epitope, with concomitant decrease in binding to IgM in human plasma. These results demonstrated that the recombinant endo-beta-galactosidase C is a valuable aid in xenotransplantation.

The ratio of splicing variants of MGC-24/CD164, a sialomucin, correlates with the metastatic potential of colorectal carcinomas

MGC-24/CD164 is a sialomucin expressed in many normal and cancerous tissues. In humans, soluble and transmembrane forms of MGC-24 are produced by alternative splicing. The total MGC-24 RNA level was found to be lower in human colorectal carcinomas as compared with the adjacent normal mucosal tissues. Lower MGC-24 mRNA levels in colon carcinomas and in the adjacent normal mucosa epithelium correlate with lymphatic vessel invasion by the carcinoma. The ratio of the soluble form to the transmembrane form of the mRNA in colorectal carcinomas was determined by ribonuclease protection assay. Higher ratios were correlated with less venous invasion and less remote metastasis, which became evident during postoperative observation.

Surgical management of Cushing's syndrome

Patients with Cushing's syndrome (137 total) who underwent adrenalectomy from 1957 through 1999 were reviewed for survival and complications. Of the 137 patients, 83 had adrenocortical adenoma, 30 Cushing's disease, seven primary pigmented nodular adrenocortical disease (PPNAD), eight adrenocorticotropin (ACTH)-independent macronodular hyperplasia, five adrenocortical carcinoma, and four ectopic ACTH syndromes. Seventy-eight patients with adrenocortical adenoma are alive, and their survival rate was equal to the age-matched control population, when patients who died of postoperative complications were excluded. Of the patients with Cushing's disease, 20 are alive, and ten of 16 patients (63%) who were followed and evaluated, had skin pigmentation. Four of 16 patients (25%) developed Nelson's syndrome. Five PPNAD patients and six with ACTH-independent macronodular hyperplasia are alive. All five adrenocortical carcinoma patients and four with ectopic ACTH syndrome died within two years after operation. The prognosis for patients with adrenocortical adenoma after unilateral adrenalectomy is excellent, though it is important to avoid operative complications. The rapid disappearance of signs and symptoms of glucocorticoid excess after total adrenalectomy is assured, and the prognosis is satisfactory under careful glucocorticoid replacement, making total adrenalectomy an alternative treatment for Cushing's disease.

Comparative study of theefficacy of removal of anti-ABO and anti-gal antibodies by double filtration plasmapheresis

Successful clinical ABO-incompatible renal transplantation has been achieved by the removal of anti-A or anti-B antibodies using double filtration plasmapheresis (DFPP). We have compared changes in the levels of anti-donor antibodies and the histopathology of the renal grafts following human ABO-incompatible allotransplantation and pig-to-baboon xenotransplantation using pretransplant DFPP. DFPP was performed on days 6, -4, -2 and -1 before the ABO-incompatible transplants (n=25) and on days -2 and 0 (immediately before reperfusion) in the xenotransplants (n=4). In two baboons (XenoTx Group I) the extent of antibody removal was comparable to that in the ABO-incompatible patients, and an even greater level of removal was achieved in another two baboons (XenoTx Group II). Anti-A and anti-B and anti-pig IgM and IgG antibodies were measured by flow cytometry. All clinical ABO-incompatible renal grafts are functioning, except two which were lost from recurrence of the original disease or from chronic rejection. Three other grafts underwent humoral rejection episodes, which were successfully treated. DFPP reduced the mean anti-A/B IgM and IgG antibody levels to 8% and 13% of pretreatment levels, respectively. After kidney transplantation, they were maintained at 37% and 46% of pre-DFPP level. No antibody binding to the transplanted kidney was detected at any time (1 h to 2 yr) after ABO-incompatible allotransplantation. In contrast, in XenoTx Group I, the same extent of antibody removal (90%) prevented hyperacute rejection, but the two grafts were rejected on days 6 and 7, respectively, from acute vascular rejection. In XenoTx Group II, the additional DFPP that was required to deplete the remaining 10% of anti-pig antibody was poorly tolerated and the two baboons died 4 h and 2 days, respectively, after renal transplantation. Although anti-pig IgM antibodies were reduced to 2% of pre-treatment level, IgM and C3 binding were detected in the graft as early as 1 h posttransplantation. These data suggest that the concentration of xeno-antigen epitopes expressed on pig organs may need to be reduced by genetic engineering to the much lower level of blood group A/B antigens on human kidneys if discordant xenotransplantation is to be successful.

Oncological problems in pancreatic cancer surgery

Despite the development of more sophisticated diagnostic techniques, it remains difficult to detect pancreatic carcinoma in the early stage. The resection rate has been increasing due to recent advances in surgical techniques and the application of extensive surgery. However, the postoperative prognosis has been poor due to commonly occurring liver metastasis. Recent molecular-biological studies have been clarifying occult liver metastasis and systemic disease in pancreatic cancer. This paper will review our experience and several problems in pancreatic cancer surgery.

Systemic T helper 2 cell activation is not sufficient for antigen-induced eosinophil recruitment into the airways

BACKGROUND

Airway eosinophilic inflammation is a characteristic feature of asthma. We have previously shown that antigen-induced eosinophil recruitment into the airways of sensitized BALB/c mice is mediated by CD4+ T cells and IL-5. However, the basis for the eosinophil recruitment into the airway are still largely unknown.

METHODS

To determine the regulatory mechanisms that control the magnitude of antigen-induced eosinophilic inflammation in the airways, we analyzed antigen-induced eosinophil and T cell infiltration into the trachea in several strains of mice, including BALB/c (H-2(d)), BALB/b (H-2(b)), C57BL/6 (H-2(b)), C57BL/10 (H-2(b)), and B10.D2 (H-2(d)) mice. In addition, cytokine production from antigen-stimulated splenocytes and the titer of antigen-specific IgE antibody in serum were assessed.

RESULTS

Antigen-induced eosinophil recruitment into the trachea in BALB/c mice was more than 20 times as abundant as that in C57BL/6 mice, the latter of which was also mediated by CD4+ T cells. In contrast, systemic Th2 responses, which were evaluated by the titers of antigen-specific IgE antibody in serum and antigen-induced IL-4 and IL-5 production from splenocytes, were similarly observed in BALB/c mice and C57BL/6 mice. In addition, the antigen-induced eosinophil recruitment into the trachea was high in BALB/b mice, like BALB/c mice, but low in B10.D2 mice.

CONCLUSIONS

Systemic Th2 responses are not sufficient for causing antigen-induced eosinophil recruitment into the airways and an undefined determinant(s) that exists in the BALB background mice rather than the H-2 haplotype is vital for the regulation of antigen-induced eosinophil recruitment into the airways.

Spontaneous rupture of hepatocellular carcinoma of the caudate lobe

A rare case of ruptured hepatocellular carcinoma (HCC) of the caudate lobe is reported. A 67-year-old man came to the hospital with complaints of abdominal pain and distension. Computed tomography (CT) showed haemoperitoneum and a mass in the caudate lobe. Angiography demonstrated a tumor stain. However, extravasation of the contrast medium was not clear. Although transcatheter arterial embolization (TAE) was performed, bleeding from the tumor could not be controlled. The caudate lobe, including the tumor, was resected. The patient died of multiple organ failure despite intensive care. This case suggests that TAE is not always effective and may not be safely or easily performed when treating ruptured HCC in the caudate lobe. This is attributed to the multiple feeding arteries of the tumor, derived from the proximal portion of the right and left hepatic arteries. If bleeding from the ruptured HCC in the caudate lobe is not controlled, immediate resection of the tumor is recommended.

Experimental studies of new embolizing material for portal vein embolization

BACKGROUND/AIMS

Preoperative portal vein embolization induces hypertrophy of the future remnant liver and atrophy of the liver to be resected. This procedure has been used recently to avoid hepatic failure in extensive hepatic resection, but an adequate embolizing material has not been developed. This experimental study investigated the embolization effect of a newly devised embolizing material in dogs.

METHODOLOGY

The left branch of the portal vein was embolized with an emulsion of polidocanol and gelatin sponge. We studied the changes in liver weight and biochemical data up to 8 weeks after embolization. Pathological examination of the embolized portal vein and radiological study of the embolizing effect were performed.

RESULTS

Complete obstruction of the portal vein was maintained until 8 weeks after embolization. Sufficient hypertrophy of the non-embolized liver and atrophy of the embolized liver were obtained during this examination. No serious complication was observed.

CONCLUSIONS

The mixture of polidocanol and gelatin sponge seems to ensure perfect portal embolization without recanalization. This embolizing material is suitable for portal embolization.

Immunohistochemical studies of colorectal cancers that developed following pelvic irradiation

Radiation therapy is believed to be a predisposing factor in the development of carcinoma. During the period from 1974 to 1997, we treated five colorectal cancers in four patients who had undergone pelvic irradiation for cervical cancer. Radiation-induced changes in the remaining bowel were recognized in all of these patients. Of the five tumors, two were histologically diagnosed as mucinous adenocarcinoma, demonstrating a higher distribution than usual: To clarify the characteristics of the tumors, we examined the frequency of mutation in K-ras and p53 genes, and the proliferating cell nuclear antigen (PCNA) proliferation activity. The K-ras and PCNA stains did not show any clear characteristics of radiation-induced colorectal cancers in comparison with ordinary colorectal cancers; however, it was of interest that strongly positive staining was observed in our mucinous adenocarcinomas, even though a low frequency of p53 gene mutation has been reported in ordinary mucinous adenocarcinomas.

Blockade of JAK2 by tyrphostin AG-490 inhibits antigen-induced eosinophil recruitment into the mouse airways

We studied the effect of tyrphostin AG-490, a specific Janus kinase 2 (JAK2) inhibitor, on antigen-induced eosinophil recruitment into the airways of sensitized mice and on IL-5-induced chemokinesis and adhesiveness of eosinophils. The in vivo administration of AG-490 prevented antigen-induced eosinophil infiltration in the airways of sensitized mice in a dose-dependent manner. However, the administration of AG-490 did not affect antigen-induced IL-5 production in the airways nor in vitro antigen-induced IL-5 production and T cell proliferation of spleen cells. Furthermore, AG-490 inhibited IL-5-induced chemokinesis and beta1-integrin adhesiveness of eosinophils in vitro. Because antigen-induced eosinophil recruitment into the airways is mediated by IL-5, these results indicate that JAK2 activation is critical for antigen-induced, IL-5-dependent mobilization of eosinophils into the tissue.

Creation and use of a composite polyurethane-expanded polytetrafluoroethylene graft for hemodialysis access

The Thoratec (Vectra) polyurethane vascular access graft (TPVA) is among the most recent additions to the list of materials used to construct prosthetic grafts for vascular access during hemodialysis. We give the TPVA very high marks, and recognize the utility of such a graft for use in hemodialysis. However, the strong elasticity of this graft can lead to unexpected complications after suturing. We devised a new surgical method using a TPVA-ePTFE (expanded polytetrafluoroethylene) composite graft, substituting the anastomosis section of the TPVA with a portion of ePTFE graft material, and have been able to overcome most of the TPVA's potential problems. We herein describe the technique.

Gallbladder torsion: case report and review of 245 cases reported in the Japanese literature

We report here a case of torsion of the gallbladder in a 73-year-old woman. The patient was admitted to our hospital with right hypochondralgia. Ultrasonography and computed tomography demonstrated a distended gallbladder, with a multilayered wall, which contained no stones. Since the symptoms did not respond to antibiotics, laparotomy was performed. The gallbladder was found to be twisted around its pedicle and to be gangrenous. Cholecystectomy was performed, and the patient had an uneventful postoperative course. We also reviewed 245 cases reported in the Japanese literature. The clinical features of gallbladder torsion, which include low frequency of fever and jaundice, poor response to antibiotic therapy, and acute onset of abdominal pain, may be helpful in the differential diagnosis from acute cholecystitis. Moreover, a highly suggestive sign of gallbladder torsion observed by ultrasonography or computed tomography is a markedly enlarged "floating" gallbladder with a continuous hypoechoic line indicating edematous change in the wall.