Akihiko Numata

Functional evaluation of tumor‐infiltrating mononuclear cells. Detection of endogenous interferon‐γ and tumor necrosis factor‐α in human colorectal adenocarcinomas

Quantitative evaluation of the levels of interferon‐γ (IFN‐γ) and tumor necrosis factor‐α (TNF‐α) in the extracts of tumors and their corresponding normal tissues resected from 43 patients with colorectal adenocarcinoma was done using solid‐phase, sandwich radioimmunoassay. The levels of both IFN‐γ and TNF‐α detected in the tumor tissues were higher than those in the corresponding normal colorectal tissues obtained from each patient. A significant negative correlation was observed between the level of IFN‐γ and TNF‐α in each tumor extract. The decrease of the level of IFN‐γ in the tumor correlated with the advance of clinical stage, and the levels of IFN‐γ of the patients with distant metastases were significantly lower than those of the patients without distant metastases. However, an increase in the level of TNF‐α correlated not only with an enlarged diameter but also with the extent of the primary tumor. Immunohistochemical staining of IFN‐γ and TNF‐α producing cells in tumor tissues showed that IFN‐γ was mainly produced by CD4 + CD8– T‐lymphocytes and TNF‐α was mainly produced by CD11c+ cells with macrophage‐like morphology. These results suggest that CD4+ T‐lymphocytes that produce IFN‐γ might play an important role in the antitumor response against cancer progression in human colorectal adenocarcinomas.

Detection of high levels of immunoreactive human beta-1 interferon in sera from HIV-infected patients

We have examined human interferon beta-1 (HuIFN-beta 1) levels in the sera from patients with various diseases by using a newly developed highly sensitive enzyme-linked immunosorbent assay system (ELISA). High levels of HuIFN-beta 1 were detected in the sera from Human Immunodeficiency Virus-I (HIV-I) infected patients, especially of asymptomatic carriers. The serum level of HuIFN-beta 1 may be a good indicator of HIV-I infection and of other immunological disorders.

Laparoscopic Nissen Fundoplication for Gastroesophageal Reflux Disease in Japan

PurposeLaparoscopic antireflux surgery is the standard treatment for gastroesophageal reflux disease (GERD) in Western countries where this disorder is common; however, it has only recently been introduced in Japan. We examined the effectiveness of laparoscopic antireflux surgery in a small series of Japanese patients.MethodsBetween 1998 and 2001 we performed laparoscopic Nissen fundoplication in 23 patients to evaluate the efficiency of this technique. We examined the following four parameters pre- and postoperatively: symptoms, endoscopic findings, gastroesophagogram findings, and the results of intraesophageal 24-h pH monitoring. We also examined the operation time, blood loss, intraoperative complications, and postoperative complications.ResultsThe operation was safely performed in all patients, regardless of age, and there were no intraoperative complications. Postoperatively, more than three parameters were effectively normalized in 17 (89.5%) of 19 patients. The only postoperative complications were delayed gastric emptying in three patients and persistent dysphagia in five patients. During follow-up, esophagitis recurred in two patients, one of whom underwent laparoscopic refundoplication, which normalized the condition.ConclusionLaparoscopic Nissen fundoplication is highly effective for GERD and could become the standard surgical treatment in Japan.

The role of TNF in listeriosis

Tumour necrosis factor (TNF), a protein produced mainly by macrophages, has diverse actions on a wide variety of cells throughout the body including leukocytes and tumour cells. It also has important biological effects in the intact host (1). TNF acts beneficially to hosts in some cases, but harmfully in other cases. The role of TNF in the pathophysiology of infectious diseases has been extensively studied. Endogenous TNF induced by infections triggers the characteristic manifestations of septicemia and bacterial meningitis (2, 3).