Protective efficacy of passive immunization with monoclonal antibodies in animal models of H5N1 highly pathogenic avian influenza virus infection.

Highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype often cause severe pneumonia and multiple organ failure in humans, with reported case fatality rates of more than 60%. To develop a clinical antibody therapy, we generated a human-mouse chimeric monoclonal antibody (MAb) ch61 that showed strong neutralizing activity against H5N1 HPAI viruses isolated from humans and evaluated its protective potential in mouse and nonhuman primate models of H5N1 HPAI virus infections. Passive immunization with MAb ch61 one day before or after challenge with a lethal dose of the virus completely protected mice, and partial protection was achieved when mice were treated 3 days after the challenge. In a cynomolgus macaque model, reduced viral loads and partial protection against lethal infection were observed in macaques treated with MAb ch61 intravenously one and three days after challenge. Protective effects were also noted in macaques under immunosuppression. Though mutant viruses escaping from neutralization by MAb ch61 were recovered from macaques treated with this MAb alone, combined treatment with MAb ch61 and peramivir reduced the emergence of escape mutants. Our results indicate that antibody therapy might be beneficial in reducing viral loads and delaying disease progression during H5N1 HPAI virus infection in clinical cases and combined treatment with other antiviral compounds should improve the protective effects of antibody therapy against H5N1 HPAI virus infection.

Emergence of H7N9 Influenza A Virus Resistant to Neuraminidase Inhibitors in Nonhuman Primates.

The number of patients infected with H7N9 influenza virus has been increasing since 2013. We examined the efficacy of neuraminidase (NA) inhibitors and the efficacy of a vaccine against an H7N9 influenza virus, A/Anhui/1/2013 (H7N9), isolated from a patient in a cynomolgus macaque model. NA inhibitors (oseltamivir and peramivir) barely reduced the total virus amount because of the emergence of resistant variants with R289K or I219T in NA [residues 289 and 219 in N9 of A/Anhui/1/2013 (H7N9) correspond to 292 and 222 in N2, respectively] in three of the six treated macaques, whereas subcutaneous immunization of an inactivated vaccine derived from A/duck/Mongolia/119/2008 (H7N9) prevented propagation of A/Anhui/1/2013 (H7N9) in all vaccinated macaques. The percentage of macaques in which variant H7N9 viruses with low sensitivity to the NA inhibitors were detected was much higher than that of macaques in which variant H5N1 highly pathogenic influenza virus was detected after treatment with one of the NA inhibitors in our previous study. The virus with R289K in NA was reported in samples from human patients, whereas that with I219T in NA was identified for the first time in this study using macaques, though no variant H7N9 virus was reported in previous studies using mice. Therefore, the macaque model enables prediction of the frequency of emerging H7N9 virus resistant to NA inhibitors in vivo. Since H7N9 strains resistant to NA inhibitors might easily emerge compared to other influenza viruses, monitoring of the emergence of variants is required during treatment of H7N9 influenza virus infection with NA inhibitors.

Efficacy of repeated intravenous administration of peramivir against highly pathogenic avian influenza A (H5N1) virus in cynomolgus macaques.

Highly pathogenic avian influenza A (H5N1) viruses cause severe and often fatal disease in humans. We evaluated the efficacy of repeated intravenous dosing of the neuraminidase inhibitor peramivir against highly pathogenic avian influenza virus A/Vietnam/UT3040/2004 (H5N1) infection in cynomolgus macaques. Repeated dosing of peramivir (30 mg/kg/day once a day for 5 days) starting immediately after infection significantly reduced viral titers in the upper respiratory tract, body weight loss, and cytokine production and resulted in a significant body temperature reduction in infected macaques compared with that of macaques administered a vehicle (P < 0.05). Repeated administration of peramivir starting at 24 h after infection also resulted in a reduction in viral titers and a reduction in the period of virus detection in the upper respiratory tract, although the body temperature change was not statistically significant. The macaque model used in the present study demonstrated that inhibition of viral replication at an early time point after infection by repeated intravenous treatment with peramivir is critical for reduction of the production of cytokines, i.e., interleukin-6 (IL-6), tumor necrosis factor α, gamma interferon, monocyte chemotactic protein 1, and IL-12p40, resulting in amelioration of symptoms caused by highly pathogenic avian influenza virus infection.

[Two cases of advanced colorectal cancer which demonstrated the reversibility of oxaliplatin-mediated increase in splenic volume].

Hepatic sinusoidal injury arises occasionally after oxaliplatin-based chemotherapy. As a result, portal hypertension associated with splenomegaly occurs in some cases. We report two cases of advanced colorectal cancer which showed splenomegaly after administration of oxaliplatin-based chemotherapy. In both cases, mFOLFOX6/bevacizumab was administered as a firstline chemotherapy. Splenic volume was determined by loading the CT images onto a commercially available workstation. In case 1, initial splenic volume was 137.82mL. Two months later, it increased to 160.96mL. After six cycles of chemotherapy, we removed oxaliplatin due to peripheral neuropathy. Consequently, the splenic volume decreased to 151.58mL. Subsequent to the reintroduction of oxaliplatin, the splenic volume increased to 177.48mL. Following two cycles of mFOLFOX6/bevacizumab, oxaliplatin was removed again. In a similar way, splenic volume decreased to 158.52mL. In case 2, initial splenic volume was 105.84mL. Ten months later, it increased to 228.54mL. After administration of mFOLFOX6/bevacizumab, we continued chemotherapy with sLV5FU2/bevacizumab and irinotecan. The splenic volume decreased to 197. 06mL. In conclusion, oxaliplatin- based chemotherapy induces an increase in splenic volume, however, it may be reversible after discontinuation of oxaliplatin.

[Two cases of colorectal cancer presenting with periodic, transient elevation of serum iron due to hemolysis after chemotherapy including 5-FU].

The serum iron level reportedly shows transient elevation after chemotherapy in some cases. However, the cause of this phenomenon has not been clearly described. We report two cases of colorectal cancer whose serum iron level demonstrated recurrent elevation after chemotherapy. Both were advanced colorectal cancer cases with liver metastases, so we started chemotherapy with modified FOLFOX6+bevacizumab. After several courses, we changed the regimen to simplified LV5FU2+ bevacizumab in both cases. The serum iron level showed transient, periodical elevation irrespective of the therapeutic regimen. Additionally, indirect bilirubin also showed transient elevation, which was completely synchronized with the fluctuation of the serum iron level. These observations suggest that hemolysis is the main cause of periodic, transient elevation of serum iron level after chemotherapy including 5-FU.

[Two cases of colorectal cancer presenting with periodic, transient elevation of serum iron after chemotherapy including irinotecan].

It is known that the serum iron level shows a transient elevation after chemotherapy in some cases; however, the cause of this phenomenon has not been clearly described. We report two cases of colorectal cancer whose serum iron level demonstrated recurrent elevation after administration of irinotecan as a second-line chemotherapy. The transferrin saturation rate showed marked elevation together with serum iron. This fact indicates that the release of non-transferrin bound iron (NTBI) occurs and then, NTBI binds with transferrin immediately thereafter. Additionally, elevation of indirect bilirubin in case 1, and mild anemia in case 2 were observed after every course of chemotherapy. All these phenomena were synchronized with the fluctuation of the serum iron level. These observations suggest that the transient elevation of the serum iron was related with the release of the NTBI from red blood cells after chemotherapy including irinotecan.

[A case of mucosa-associated lymphoid tissue lymphoma with penicillin allergy successfully treated with levofloxacin, minomycin and rabeprazole].

A 52-year-old Japanese woman was referred to our Institute because of Helicobacter pylori(H. pylori)-positive gastric mucosa-associated lymphoid tissue(MALT)lymphoma. Since she had a penicillin allergy, we could not eradicate H. pylori using the standard triple therapy including amoxicillin. Additionally, H. pylori was resistant to both clarithromycin and metronidazole. So she was treated with minomycin (MINO), levofloxacin (LVFX), and rabeprazole (RPZ) based on a drug sensitivity test. MINO+LVFX+RPZ appear to be a promising, appropriate, and well-tolerated eradication regimen for H. pylori demonstrating resistance to both clarithromycin and metronidazole, and for patients who are allergic to penicillin.

[Management system of cancer chemotherapy regimens].

Cancer chemotherapy regimens which had been used at a ward and outpatient chemotherapy in various departments were collected and made available to everybody in October, 2003. However, it was difficult to manage cancer chemotherapy regimens in real time, from the viewpoint of risk management. Then, the Cancer Chemotherapy Center took the leading part and established a chemotherapy exploratory committee, which consists of 4 doctors, 2 nurses and 2 pharmacists, in June, 2006. The department of pharmacy could control all cancer chemotherapy regimens by this system, and lead the proper use of increasing anticancer agents. Inquiries on prescription by the pharmacist contributed to proper medical treatment. The role of the cancer chemotherapy exploratory committee and its outcome are described for the purpose of the prevention of medical accidents in this paper.

Key parameters of sperm motion in relation to male fertility in rats given alpha-chlorohydrin or nitrobenzene.

This study was undertaken to detect key parameters of rat sperm motion in relation to male fertility by comparing the differences in sperm motion induced by treatment with alpha-chlorohydrin (ACH), known to produce spermatotoxicity, and nitrobenzene (NTB), known to produce testicular toxicity. Male rats received ACH (5 or 20 mg/kg/day) or NTB (60 mg/kg/day) for either 3 days or 18 days. Epididymal sperm was assessed for motility using a Hamilton-Thorne Sperm Analyzer (HTM-IVOS). Numerical data for statistical analysis and graphical renditions of sperm motion using parameters in radar charts and reconstructed sperm tracks were analyzed to evaluate sperm motion. Males were allowed to copulate with untreated females and cesarean sections were conducted in order to examine the effects of drug administration on male fertility. Linearity of sperm track (linearity (LIN) and/or straightness (STR)) decreased and/or beat cross frequency (BCF) increased only in ACH groups (5 or 20 mg/kg/day), although the percentage of motile sperm, sperm velocities (average path velocity (VAP), curvilinear (VCL), and straight line velocity (VSL)) and amplitude of lateral head displacement (ALH) decreased on Day 18 in both ACH and NTB (60 mg/kg/day) groups. Furthermore, from the individual reconstructed sperm tracks, it was clear that ACH-treated spermatozoa were characterized by abnormal motion ("jerking") with low vigor (low velocities) and little or no forward progression. Finally, only ACH treatment led to a reduction in pregnancy rate or infertility. Therefore, our results suggest that linearity (especially VSL, STR and LIN) in sperm motion is a key parameter for assessing a chemical's potential to induce male infertility.

Influence of obesity on blood pressure and arterial stiffness in the early teens.

PROBLEM: We studied the influence of adiposis on the progression of blood pressure and arteriosclerosis in the early teens. METHODS: The subjects of this study were 147 boys and girls (72 boys and 75 girls) in junior high school. Height, weight, percentage body fat, blood pressure, brachial-ankle pulse wave velocity (baPWV) and exercise time were measured. All subjects were measured at two points--at 5th grade in elementary school (ages between 10 and 11 years) and 2nd grade in junior high school (8th grade, ages between 13 and 14 years). The relationship between the change values of adiposis over 3 years (from 5th grade to 8th grade) and blood pressure/baPWV at the age of 13-14 were analyzed with multiple regression analysis. RESULTS: For boys, the change values in BMI and percentage body fat were correlated positively with systolic blood pressure. For girls, the change values in BMI and percentage body fat were correlated positively with systolic and diastolic blood pressures and baPWV. CONCLUSIONS: In conclusion, raised blood pressure was already observed in obese early teens as a result of arteriosclerosis progression regardless exercise habit, and it was more apparent in girls.

Pathogenicity of pandemic H1N1 influenza A virus in immunocompromised cynomolgus macaques.

Pandemic (H1N1) 2009 influenza virus spread throughout the world since most people did not have immunity against the virus. In the post pandemic phase when many humans might possess immunity against the pandemic virus, one of the concerns is infection in immunocompromised people. Therefore, we used an immunosuppressed macaque model to examine pathogenicity of the pandemic (H1N1) 2009 virus under an immunocompromised condition. The virus in nasal samples of immunosuppressed macaques infected with the pandemic (H1N1) 2009 virus was detected longer after infection than was the virus in nasal samples of immunocompetent macaques. As expected, not only virus amounts but also virus propagation sites in the immunosuppressed macaques were larger than those in lungs of the immunocompetent macaques when they were infected with the pandemic virus. Immunosuppressed macaques possessed low levels of immune cells producing cytokines and chemokines, but levels of inflammatory cytokines/chemokine interleukin (IL)-6, IL-18, and monocyte chemotactic protein (MCP)-1 in lungs of the immunosuppressed macaques were higher than those in lungs of the immunocompetent macaques, though the differences were not statistically significant. Therefore, under an immunosuppressive condition, the pandemic influenza (H1N1) 2009 virus might cause more severe morbidity with high cytokine/chemokine production by the host innate immune system than that seen in macaques under the immunocompetent condition.

Protection against H5N1 highly pathogenic avian and pandemic (H1N1) 2009 influenza virus infection in cynomolgus monkeys by an inactivated H5N1 whole particle vaccine.

H5N1 highly pathogenic avian influenza virus (HPAIV) infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3), in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1) 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3.