Hidenori Hata

HBcAg-specific CD8 T cells play an important role in virus suppression, and acute flare-up is associated with the expansion of activated memory T cells

We analyzed the prevalence and longitudinal fluctuation of hepatitis B virus (HBV)-specific CD8 T cells in chronic HBV infection using an HLA-A2–HBc18-27 tetramer. Thirty-five HLA-A2-positive patients with chronic HBV infection were divided into 17 HBe antigen (HBeAg)-positive and 18 anti-HBe antibody (anti-HBe)-positive patients. Five HLA-A2-positive normal subjects, five HLA-A2-negative patients with chronic HBV infection, and two HLA-A2-positive patients with acute HBV infection were included as controls. HBc18-27-specific CD8 T cells (c18-27-CD8Ts) were detected at a significantly higher prevalence in patients with anti-HBe (6/18) than in those with HBeAg (1/17), and their frequency reached 0.28% of the total CD8 T cells. The prevalence was significantly higher in patients with HBV DNA below 4.0 log genome equivalents (LGE)/ml (5/12) than in those with HBV DNA above 4.0 LGE/ml (2/23). The frequency of c18-27-CD8Ts was consistently higher in liver-infiltrating lymphocytes, ranging from 0.18 to 1.28%, than in autologous peripheral blood lymphocytes. Longitudinal analysis of patients with acute flare-up demonstrated that the elevation of alanine aminotransferase (ALT) was intimately associated with the expansion of c18-27-CD8Ts. Phenotypic analysis revealed that most c18-27-CD8Ts during acute flare-up expressed HLA-DR and CCR5, while those during low-ALT periods showed low expression. Furthermore, most liver-infiltrating c18-27-CD8Ts were positive for HLA-DR and CCR5, suggesting selective recruitment of activated c18-27-CD8Ts into the liver. In conclusion, HBV-specific CD8 T cells play an important role in the suppression of virus replication, and acute flare-up is associated with the expansion and activation of HBV-specific memory cells.

A target-controlled infusion system with bispectral index monitoring of propofol sedation during endoscopic submucosal dissection

Background and study aims: Propofol administration via a target-controlled infusion system with bispectral index monitoring (BIS/TCI system) is expected to prevent complications from sedation during complex and long endoscopic procedures. We evaluated the feasibility of setting the BIS/TCI system for non-anesthesiologist administration of propofol (NAAP) during endoscopic submucosal dissection (ESD). Patients and methods: From May 2009 to February 2013, 250 patients with esophagogastric neoplasms were treated with ESD using the BIS/TCI system with NAAP. In the TCI system, the initial target blood concentration of propofol was set at 1.2 μg/mL. The titration speed of propofol was adjusted according to the BIS score and the movement of the patient. The BIS target level ranged from moderate to deep sedation, at which a stable BIS score between 60 and 80 was obtained. Results: In 80.4 % of patients, it was possible to maintain stable sedation with a blood concentration of propofol of less than 1.6 µg/mL using TCI throughout the ESD procedure. The default setting for ideal blood concentration of propofol was 1.2 μg/mL, because the medians of the lower and upper bounds of blood concentration were 1.2 μg/mL (range 0.6 – 1.8 μg/mL) and 1.4 μg/mL (range 1.0 – 3.8 μg/mL), respectively. Although hypotension occurred in 27 patients (10.8 %), oxygen desaturation occurred in only nine patients (3.6 %), and severe desaturation in only two patients (0.8 %). Conclusions: Using our settings, it is possible for a non-anesthesiologist to maintain stable sedation during a lengthy endoscopic procedure through propofol sedation with a BIS/TCI system.

Inhibition of RL male 1 tumor growth in BALB/c mice by introduction of the RLakt gene coding for antigen recognized by cytotoxic T-lymphocytes and the GM-CSF gene by in vivo electroporation

A DNA vaccine for inducing a tumor immune response was investigated using a well‐characterized murine model tumor antigen. We demonstrated that in vivo electroporation augmented the induction of IFNγ enzyme‐linked immunospot (ELISPOT) and cytotoxic T lymphocyte (CTL) generation against pRL1a peptide in BALB/c spleen cells upon immunization with RLakt plasmid. Immunization without in vivo electroporation resulted in only a marginal induction of IFNmG ELISPOT and CTL generation. Furthermore, co‐injection of GM‐CSF and RLakt plasmids significantly enhanced the induction of IFNmG ELISPOT and CTL generation compared to the injection of RLakt plasmid alone. Inhibition of RL male 1 tumor growth was observed by injecting BALB/c mice with GM‐CSF and RLakt plasmids using in vivo electroporation, although no effect was observed against an established tumor using the same treatment. No growth inhibition was observed without in vivo electroporation. Immunization with either RLakt plasmid alone, or GM‐CSF and pCIneo control plasmids using in vivo electroporation did not inhibit RL male 1 tumor growth.

Cryptic CTL Epitope on a Murine Sarcoma Meth A Generated by Exon Extension as a Novel Mechanism

Using the recently developed ELISPOT cloning methodology, we obtained cDNA clone S35 coding for the Ag epitope recognized by a murine sarcoma Meth A-specific CTL clone AT-1. Analysis of truncated S35 constructs and overlapping peptides revealed that the peptide epitope was LGAEAIFRL. AT-1 CTL lysed peptide-pulsed CMS8 cells at a nanomolar concentration, and the peptide strongly stimulated IFN-γ production in AT-1 CTL. Sequence homology indicated that the S35 was derived from a mouse homologue of human retinoic acid-regulated nuclear matrix-associated protein (ramp). The ramp gene consisted of 15 exons. The majority of the ramp mRNA was the transcript normally spliced between exons 14 and 15, but a minor population of mRNA with an extended exon 14 was also present in Meth A cells. The epitope was derived from the newly created open reading frame, which resulted from extension of exon 14 after splicing of the adjacent intronic sequence.

エトポシドとシスプラチンの併用療法（EP療法）が著効し組織学的CRが得られた肝原発小細胞癌の1切除例

A 52-year-old woman was admitted to our hospital with right upper quadrant pain with gallbladder wall thickening and multiple liver tumors. Endoscopic ultrasound-guided biopsy revealed small cell carcinomas of both the gallbladder and liver. After 10 cycles of chemotherapy with etoposide and cisplatin, marked shrinkage of the tumors was evident on computed tomography. The patient subsequently underwent hepatectomy and resection of the extrahepatic bile duct and gallbladder with curative intent. Although no viable tumor cells were found in the resected specimens, we confirmed phagocytosis of tumor cells killed by chemotherapy in the resected liver specimen. Therefore, we suspected that the patient had primary small cell carcinoma of the liver that had been successfully treated. This is a rare case of primary small cell carcinoma of the liver that showed pathological complete response to chemotherapy with etoposide and cisplatin.