CD4-CD8- T cells bearing invariant Valpha24JalphaQ TCR alpha-chain are decreased in patients with atopic diseases

Atopic disorders are caused by disregulated activation of T helper 2 (Th2) cells that produce IL-4 and IL-5. Because the presence of IL-4 potently augments the differentiation of naive T cells into Th2 cells, it is important to seek the cell population which provides IL-4 for naive T cells. Recently, a unique subpopulation of T cells, natural killer (NK) T cells, has been shown to produce a large amount of IL-4 upon activation, suggesting their regulatory role in initiation of Th2 cell differentiation. To determine whether NK T cells play a regulatory role in human Th2 cell-mediated atopic diseases, we analysed the frequency of invariant Valpha24JalphaQ CD4-CD8- double-negative (DN) T cells, human NK T cells, in patients with atopic asthma and atopic dermatitis. We also studied cytokine production from Valpha24+ Vbeta11+ DN T cells, which comprise most of Valpha24JalphaQ DN T cells. We found that the invariant Valpha24JalphaQ DN T cells were greatly diminished in patients with asthma and atopic dermatitis. On the other hand, there was no significant difference in Valpha24+ CD4+ T cells possessing invariant Valpha24JalphaQ TCR between healthy subjects and atopic patients. We also found that Valpha24+ Vbeta11+ DN T cells from healthy subjects predominantly produced interferon-gamma (IFN-gamma) but not IL-4 upon activation. These results suggest that NK T cells may not be essential for human atopic disease and that the disappearance of NK T cells, most of which produce IFN-gamma, may be involved in the pathogenesis of atopic diseases.

Characterization of high-grade neuroendocrine tumors of the lung in relation to menin mutations

It has been suggested that mutations in the menin gene play a role in the development of multiple endocrine neoplasia type 1 (MEN1)-associated and of sporadic forms of low- and intermediate-grade neuroendocrine tumors of the lung. In the present study, eight tumor specimens of large cell neuroendocrine carcinoma (LCNEC) and 13 of small cell lung cancer (SCLC), which represent a high-grade category of neuroendocrine tumors, were examined for the potential involvement of menin alterations as well as for the expression of various neuroendocrine markers and p53 and Rb abnormalities. All specimens expressed multiple neuroendocrine markers as expected and almost invariably carried p53 and Rb alterations. Unexpectedly, however, mutations in the menin gene were not detected in any of the high-grade neuroendocrine tumors examined. We thus conclude that menin mutations do not play a crucial role in the pathogenesis of high-grade subsets, in contrast to their suggested significant role in the development of low- and intermediate-grade subsets. Interestingly, loss of heterozygosity (LOH) in the menin gene appeared to be more prevalent in LCNEC (50%) than in SCLC (22%), suggesting a possible distinction between SCLC and LCNEC.

Clonal expansion of T cells infiltrating in the airways of non-atopic asthmatics

CD4+ T cells are thought to play an important role in airway inflammation in both atopic and non-atopic asthma. However, the mechanism by which T cells are activated in non-atopic asthma, where there is no causative antigen identified, is unknown. To elucidate this issue, we analysed T cell receptor (TCR) Vbeta gene clonotypes of T cells in the bronchoalveolar lavage fluids (BALF) of non-atopic asthmatics using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis and a sequencing method. We found that the numbers of TCR Vbeta gene clonotypes of T cells in the BALF of non-atopic asthmatics were significantly increased compared with those of peripheral blood lymphocytes (PBL). We also found that there were several shared amino acid motifs in complementarity-determining region 3 (CDR3) of TCR Vbeta genes from those T cell clones in BALF of non-atopic asthmatics, whereas these shared motifs were not found in the same Vbeta family genes from PBL in the patients. Moreover, a conserved amino acid sequence was detected in two patients who shared a common HLA-DR allele. These results indicate that the infiltrating T cells in the airways of non-atopic asthmatics recognize relatively limited epitopes of antigens and are clonally expanded by antigen-driven stimulation.

Ligation of the T cell receptor complex results in phosphorylation of Smad2 in T lymphocytes

TGF-beta modulates immune responses by regulating T cell function. The Smad family of proteins has been recently shown to transduce signals for the TGF-beta superfamily and Smad2 mediates TGF-beta signaling. Here, we showed that TGF-beta phosphorylated Smad2 and induced interaction between Smad2 and Smad4 in primary T cells and the Jurkat T cell line. Interestingly, ligation of the T cell receptor (TCR)/CD3 complex with anti-CD3 mAb also phosphorylated Smad2, but failed to induce interaction between Smad2 and Smad4 in the Jurkat T cell line. Phosphorylation of Smad2 via the TCR/CD3 complex was not abrogated by treatment with neutralizing antibody against TGF-beta. Furthermore, PD98059, a MEK inhibitor, suppressed Smad2 phosphorylation by stimulation with anti-CD3 mAb in Jurkat T cell line. These findings indicated that not only TGF-beta but also stimulation via the TCR/CD3 complex phosphorylated Smad2 through mitogen-activated protein (MAP) kinase cascades, suggesting that Smad2 may function in both TGF-beta- and TCR/CD3 complex-mediated signaling pathways in T cells.

Crohn's disease mimicking as bowel endometriosis. Are the symptoms reduced by nafarelin acetate?

We report a 27-year-old female with Crohn's disease clinically misdiagnosed with intestinal endometriosis. Her complaints were abdominal pain and fullness, which occurred monthly during her menstrual period. Although we had no histopathological evidence, we diagnosed her as bowel endometriosis on the basis of her clinical course. Since nafarelin acetate therapy started, the symptoms due to mechanical subileus have improved. The transverse colon, a 70 cm segment of the ileum, including the terminal ileum, were resected because of repeated symptoms of bowel obstruction despite prolonged nafarelin therapy. Histopathological findings of the resected specimen revealed Crohn's disease without endometrial tissue. In our patient, an increased cortisol and ACTH secretion, a side effect of nafarelin, was noted during the therapy. This case showed that nafarelin therapy could increase serum concentration of ACTH and cortisol, which was considered to suppress the pathology of Crohn's disease by its anti-inflammatory action. We emphasize that intestinal examination must be performed with Crohn's disease in mind, even if nafarelin acetate is effective.

[New classification of the T category for pancreatic cancer]

The General Rules for the Study of Pancreatic Cancer (4th edition) is widely used in Japan, but several problems have been detected. One is the complexity of classification of the T category of peripancreatic invasion. This study was undertaken to simplify the classification of the T category. In 145 patients who underwent resection of pancreatic cancer, we analyzed the prognosis of those with invasion and without invasion based on seven factors of peripancreatic invasion. Furthermore, we selected three factors (S, invasion to the anterior pancreatic capsule; RP, invasion to the retroperitoneal tissue; and PL, invasion to the extrapancreatic nerve plexus) as prognostic factors by means of stepwise multivariate linear regression analysis. Subsequently we established a new classification of the T category: T1, without invasion in all three factors; T2, with invasion in only one of the three factors; and T3, with invasion in two or three factors. The prognoses of the same patients were analyzed retrospectively, and 1-, 3-, and 5-year survival rates were 100%, 88%, and 44% in T1, 76%, 30%, and 18% in T2, and 27%, 4%, 3% in T3 patients, respectively. In conclusion, we suggest that our new classification of the T category is simple and useful for the assessment of the prognosis in pancreatic cancer.

An in vivo approach showing the chemotactic activity of leukotriene B(4) in acute renal ischemic-reperfusion injury

Neutrophil migration protects the body against foreign invasion. Sequestration and activation of neutrophils, however, require stringent regulation because they may also cause tissue damage by the release of lysosomal enzymes and reactive oxygen species. The activity of various chemoattractants [e.g., leukotriene B(4) (LTB(4)), interleukin-8, and complements] has been documented by in vitro assays, whereas in vivo data have been limited mostly to histology. To examine in an in vivo model the chemotactic activity and subsequent tissue infiltration and the role of a specific chemoattractant, LTB(4), we used a rat renal ischemia-reperfusion injury model. Fluorescence-labeled Chinese hamster ovary (CHO) cells stably expressing the LTB(4) receptor (CHO-BLT) were able to accumulate along with neutrophils in the postischemic kidney, in contrast to vector control CHO cells. Furthermore, LTB(4) antagonists that protect against the decrease in renal function and diminish the tissue myeloperoxidase activity also led to the marked decrease in the number of CHO-BLT cells and neutrophils. Thus, LTB(4) alone appears sufficient to cause cells to migrate into postischemic tissues, and its dominant role in reperfusion injury has been demonstrated. The utilization of transfectants to pinpoint the role of LTB(4) in these in vivo experiments suggests their potential use with other ligands and/or in other pathological conditions.

Gastric perforation caused by a bulimic attack in an anorexia nervosa patient: report of a case

We report a rare case of gastric perforation due to a bulimic attack in a 17-year-old girl suffering from anorexia nervosa. She was admitted to our hospital with the chief complaint of abdominal pain following bulimia. Initially, her symptoms were reduced after drainage using a nasogastric tube. Eight hours later, however, she fell into a state of preshock. Abdominal radiography revealed subphrenic free air. We diagnosed the patient as having diffuse peritonitis. At laparotomy, the stomach was dilated and necrotic with perforation. Almost the entire stomach was resected. Postoperatively, the patient recovered uneventfully. We should therefore be aware of this condition when treating patients with anorexia nervosa who complain of abdominal pain.

Increased leukotriene A(4) hydrolase expression in the heart of angiotensin II-induced hypertensive rat

Leukotriene A(4) (LTA(4)) hydrolase is essential for the conversion of LTA(4) to LTB(4), an inflammatory lipid mediator. We investigated whether LTA(4) hydrolase was regulated in the heart by angiotensin II (ang II) infusion. Continuous ang II infusion via an osmotic minipump for up to 7 days upregulated mRNA and protein levels of LTA(4) hydrolase ( approximately 3.5-fold of control) in the heart in a pressor-dependent manner. Immunohistochemistry demonstrated intense LTA(4) hydrolase staining in the myofibroblast as well as migrated monocytes/macrophages. These data suggest that the cardiac LTA(4) hydrolase-LTB(4) system plays a positive role in the promotion of cardiac inflammation in hypertension.

Effects of nafamostat mesilate, a synthetic protease inhibitor, on immunity and coagulation after hepatic resection

BACKGROUND/AIMS

Effects of nafamostat mesilate (NM), a serine protease inhibitor, on both coagulation-fibrinolysis activity and post-operative changes in immune responsiveness were investigated in a clinical study of 20 patients who underwent an extensive hepatic resection.

METHODOLOGY

The patients were randomly allocated into 2 groups of 10 patients each: The NM group was administered nafamostat mesilate (2 mg/kg/day) during and after the operation for 7 days. The control group received standard post-operative intensive therapies except NM.

RESULTS

The post-operative increase in coagulation in the control group was significantly suppressed in the NM-treated group on post-operative day (POD) 7. Natural killer (NK) activity, which was impaired after the operation, was recovered in the NM group on POD 7 and was significantly higher than in the control group. Helper/suppressor ratios of T lymphocytes were significantly increased post-operatively by the administration of NM.

CONCLUSIONS

These results demonstrate that NM controls the enhanced coagulation which occur in patients with extensive hepatic resection. It is also suggested that NM promptly restores the impaired immune responsiveness and decreases the risk of post-operative complications, as well as the risk of recurrence in patients with hepatic tumors.

Intraperitoneal delivery of hrR3 and ganciclovir prolongs survival in mice with disseminated pancreatic cancer

BACKGROUND AND OBJECTIVES; Intraperitoneal dissemination of pancreatic cancer is associated with a poor prognosis. Surgical resection does not prolong survival. Here we describe a novel approach to this difficult clinical problem consisting of intraperitoneal delivery of the herpes simplex virus (HSV) vector (hrR3) to mice with peritoneal dissemination of the pancreatic cancer cells.

METHODS

The human pancreatic cancer cell line (SW1990) was implanted into the abdominal cavity of nude mice. Fifteen days later, the abdominal neoplasm was treated by intraperitoneal injection of the replication-conditional HSV vector (hrR3). The mutant lacks the ribonucleotide reductase gene, but contains an intact HSV-tk gene. Beginning 5 days after vector injection, mice were treated with a 14-day course of ganciclovir.

RESULTS

Long-term survival (150 days) was seen in 70% of mice receiving hrR3 and ganciclovir, 40% of mice receiving hrR3 alone, and 0% of untreated mice. No vector-related mortality was observed. X-Gal tissue staining revealed blue-stained cells only in tumor nodules, not in normal organs.

CONCLUSIONS

Intraperitoneal delivery of hrR3 and ganciclovir improves survival in this murine model of peritoneal dissemination of pancreatic cancer. The ability of hrR3 to replicate only in rapidly dividing cells makes this virus an attractive vector for gene therapy of cancer.

Portal venous gas associated with splenic abscess secondary to colon cancer

We report a successfully treated case accompanied by portal venous gas, which was associated with splenic abscess due to penetration of colon cancer. In June, 1998, a 67-year-old Japanese man was referred to our hospital because of a continuous fever over 40 degrees C and portal venous gas detected by computed tomography (CT). CT revealed low density areas in the spleen and wall thickening of the descending colon next to the spleen. Barium-enema examination demonstrated an extrinsic filling defect in the splenic flexure of the colon. Splenectomy, resection of the pancreatic tail and left hemicolectomy were performed Histopathological studies showed moderately differentiated adenocarcinoma, which made a fistula at the bottom of the ulceration to the spleen. The postoperative course was uneventful. The portal venous gas was likely to have resulted from a bacterial infection in the portal venous systems secondary to the splenic abscess.

Tumor necrosis factor-alpha mediates antiapoptotic signals partially via p38 MAP kinase activation in human eosinophils

Tumor necrosis factor-alpha (TNF-alpha) is a proinflammatory cytokine with many biological effects on a variety of cells. In particular, TNF-alpha has been shown to act as a death or survival factor which mediates apoptosis or antiapoptotic signals in various types of cells. In eosinophils, TNF-alpha has been reported to activate eosinophil functions. However, it is not clearly defined whether TNF-alpha delivers antiapoptotic signals in eosinophils. In order to determine whether TNF-alpha prevents eosinophil apoptosis, we examined the effect of TNF-alpha on eosinophil apoptosis by the survival assay and cell cycle analysis. We also determined whether intracellular MAP kinases (ERKs, Jun kinase/JNK, and p38 MAP kinase) are involved in the TNF-alpha-induced signaling for the prevention of eosinophil apoptosis. We showed that TNF-alpha mediated antiapoptotic signals in human eosinophils in part via activation of p38 MAP kinase, but not via activation of ERKs and JNK. Our data suggest that TNF-alpha/p38 MAP kinase pathways are involved in the regulation of eosinophil survival and, thus, would be important for the development of allergic eosinophil-rich inflammation.

[Treatment of solid tumor by a direct electric current]

This is a case report of a 37-year-old Japanese married female with laryngeal sarcoma, treated by direct electric current so as to obtain remission for more than 4 years without signs of recurrence. Due to her hoarseness and laryngeal numb feeling she underwent a laryngeal examination including a biopsy, resulting in a diagnosis of sarcoma. She refused a total laryngectomy and was given Cobalt treatment of 40 Grey. In the following several months, no improvement was observed, objectively or subjectively. In Nagoya University Hospital the patient then received direct electric current therapy of 36 Coulombs through two platinum electrodes inserted into the tumor under a CT guide, pericutaneously. Two months later, as the hoarseness remained in spite of some improvement, she underwent another session of direct electric current therapy of 14.4 Coulombs through the platinum electrodes by bronchoscope-guided direct insertion. Her hoarseness soon disappeared thereafter and there was a regression of the tumor in 6 months. She did well thereafter without any signs of recurrence for 4 years. Clinical treatment of solid tumors with electric treatment with direct electric current has been done in more than 8,000 cases with CR in 25% of all cases and PR in 50%. Its mechanism, however, remains unclear. In our experimental animal studies, apoptosis was observed. It is considered that this electric therapy using direct electric current will be recognized as one method to treat solid tumors.

Hyperphosphatemia accelerates parathyroid cell proliferation and parathyroid hormone secretion in severe secondary parathyroid hyperplasia

We studied the role of phosphorus retention in parathyroid cell proliferation and parathyroid hormone (PTH) oversecretion in severe secondary parathyroid hyperplasia. Mice transplanted with human parathyroid tissue from a patient who had undergone parathyroidectomy for severe secondary hyperparathyroidism were divided into four groups; each group was given a diet with a different phosphorus content (0.4, 0.7, 1.0, and 1.2%) to alter serum phosphorus concentrations. Histologic examinations of grafts by hematoxylin-eosin or by bromodeoxyuridine (BrdU) immunohistochemical staining were performed to assess parathyroid cell proliferation. Changes in serum phosphorus concentrations unidirectionally affected PTH secretion from the graft, because human PTH did not cross-react with mouse PTH. Serum phosphorus concentrations of 1.0P and 1.2P groups were significantly higher than those of 0.4P and 0.7P groups (p<0.05). Serum phosphorus concentrations were significantly correlated with the gradient of human PTH elevation with a coefficient of 0.48 and a p<0.05. Furthermore, serum phosphorus concentrations and the gradient of human PTH elevation were significantly higher in mice with BrdU-immunoreactive cells in the parathyroid graft than in mice without immunoreactive cells in the graft. These results indicate that uncontrolled hyperphosphatemia may accelerate the proliferation of parathyroid cells, exacerbating PTH oversecretion.

Cloning and characterization of rat leukotriene B(4) receptor

Leukotriene B(4) (LTB(4)) is a potent chemoattractant for neutrophils and eosinophils. cDNAs for LTB(4) receptor (BLT) have been cloned from human, mouse, and guinea pig. Here we report the isolation of BLT from rat genomic library. Rat BLT consists of 351 amino acids with homologies of 80.2, 93.2, and 71.6%, to human, mouse, and guinea pig BLT, respectively. When expressed in human embryonic kidney (HEK)-293 cells, rat BLT showed a specific and high-affinity binding to LTB(4) with a Kd value of 0.68 nM (mean, n = 3). Northern blot analysis showed that BLT is exclusively expressed in polymorphonuclear leukocytes. Furthermore, the expression of BLT was high in proteosepeptone-activated peritoneal macrophages, while the resident macrophages did not show significant expression. The present results suggest important roles of LTB(4) in macrophage recruitment and activation.

Peritoneal washings cytology combined with immunocytochemical staining in pancreatic cancer

BACKGROUND/AIMS

Peritoneal washings from patients with pancreatic cancer demonstrate malignant cells in 0-58% of patients. But the significance of their potential for implantation and growth after radical surgery has not been clarified.

METHODOLOGY

Peritoneal washings were collected from 74 consecutive pancreatic cancer patients during a 5-year period and studied by conventional staining and immunocytochemical staining using anti-CEA and anti-CA 19-9. Fifty of the 74 patients were resectable and the others were nonresectable.

RESULTS

Seven out of 8 patients with macroscopic peritoneal metastasis were positive in conventional staining, but all 8 patients were positive in immunocytochemical staining. Five of the 66 (8%) patients without macroscopic peritoneal metastasis were positive in conventional staining, but the positive rate increased to 14 of 66 (22%) in immunocytochemical staining. There was no statistically significant difference in post-operative cumulative survival rate between the 13 positive cytology patients and 37 negative cytology patients without macroscopic peritoneal metastasis.

CONCLUSIONS

The positive rate of peritoneal washings cytology was increased in this study by the use of immunocytochemical staining in addition to conventional staining. No statistically significant difference in post-operative cumulative survival rate between positive cytology patients and negative cytology patients without macroscopic peritoneal metastasis was observed.

The effect of intraportal administration of prostaglandin E1 on liver blood flow and liver function

BACKGROUND/AIMS

Prostaglandin E1 (PGE1) exerts a hepatic cytoprotective action directly and indirectly through enhancing hepatic blood flow. Although PGE1 is usually administered systemically, more than 60% of PGE1 is inactivated during only a single passage through the lung. By administering PGE1 intraportally the intrahepatic level of this drug can be increased effectively and liver dysfunction might be prevented. In this study, the effect of intraportal administration of PGE1 to patients who underwent hepatectomy was estimated.

METHODOLOGY

Twenty patients who underwent hepatectomy from January 1995 to December 1996 were divided into 2 groups, i.e., a PGE1 group (n=8) and a control group (n=12). Laboratory data and hepatic portal blood flow were examined before and after hepatectomy. In the PGE 1 group, PGE 1 was continuously infused at a dose of 120 microg/day for 5 days through a catheter inserted into the portal vein via the gastroepiploic vein.

RESULTS

There was no difference in the post-operative change in aspartate aminotransferase (AST) or alanine aminotransferase (ALT) between the 2 groups. Elevation of total bilirubin was more significantly suppressed in the PG group than in the control group. Total branched-chain amino acids and the tyrosine ratio reached their peak on the 5th post-operative day (POD) and were significantly higher in the PG group. Post-operative portal blood flow was significantly increased in the PG group.

CONCLUSIONS

Our results indicated that continuous intraportal administration of small doses of PGE1 is effective for the protection of hepatic function after hepatectomy.

Intravascular ultrasonography for assessment of portal vein invasion by pancreatic carcinoma

Intravascular ultrasonography (IVUS) was performed to diagnose portal vein invasion by pancreatic carcinoma. In 55 patients with pancreatic carcinoma, the intravascular ultrasonographic catheter was introduced during operation through a branch of the superior mesenteric vein into the intrahepatic portal vein. The catheter was gradually withdrawn, and the cross-sectional images of the area under investigation were recorded. Altogether 45 patients underwent resection, and 34 underwent combined resection of the portal vein. The IVUS findings were compared with the histologic findings of the resected specimen, preoperative computed tomography (CT), and arterial portogram. The wall of the portal vein was visualized as an echogenic band with a thickness of 0.5 to 1.0 mm. A subtle portal vein invasion can be detected by observing this portal vein wall. For the diagnosis of portal vein invasion, the sensitivity, specificity, and overall accuracy of IVUS were 99.6%, 92.3%, and 94. 5%, respectively. The equivalent values for portography were 79.3%, 61.5%, and 70.9%; and those for CT were 82.1%, 74.1%, and 78.1%. IVUS provides more valuable and accurate information on portal vein invasion by pancreatic carcinoma than either CT or portography.

Interleukin-18 enhances antigen-induced eosinophil recruitment into the mouse airways

Interleukin-18 (IL-18) has recently been identified as an IFN-gamma-inducing factor. Previous studies have shown that CD4(+) T cells, IL-5, and TNF-alpha mediate, but IFN-gamma and IL-12 (via IFN-gamma production) inhibit antigen-induced eosinophil recruitment into the airways of sensitized mice. Here, we showed that the administration of recombinant murine IL-18 enhanced antigen-induced eosinophil recruitment into the trachea and bronchoalveolar lavage fluids (BALF) of sensitized mice in a dose-dependent manner. The administration of IL-18 enhanced antigen-induced IFN-gamma and TNF-alpha production, but not IL-5 production, in the BALF and lungs of sensitized mice. Neutralizing antibody against TNF-alpha prevented antigen-induced eosinophil recruitment into the BALF of sensitized mice. Although IL-18 enhanced antigen-induced airway eosinophilia, IL-18 did not affect antigen-induced airway hyperresponsiveness in sensitized mice. These results indicate that IL-18, unlike IFN-gamma and IL-12, enhances antigen-induced eosinophil recruitment into the airways in part by increasing antigen-induced TNF-alpha production of sensitized animals. These findings suggest that IL-18 may contribute to the development and exacerbation of airway inflammation in asthma.