著者
Hidenori Ando Sherif E. Emam Yoshino Kawaguchi Taro Shimizu Yu Ishima Kiyoshi Eshima Tatsuhiro Ishida
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.44, no.6, pp.844-852, 2021-06-01 (Released:2021-06-01)
参考文献数
45
被引用文献数
10

Acidic extracellular pH (pHe) is characteristic of the tumor microenvironment. Several reports suggest that increasing pHe improves the response of immune checkpoint inhibitors in murine models. To increase pHe, either sodium bicarbonate (NaHCO3) or citric acid/potassium-sodium citrate (KNa-cit) was chronically administered to mice. It is hypothesized that bicarbonate ions (HCO3−), produced from these alkalinizing agents in vivo, increased pHe in the tumor, and excess HCO3− eliminated into urine increased urinary pH values. However, there is little published information on the effect of changing serum HCO3− concentrations, urinary HCO3− concentrations and urinary pH values on the therapeutic outcomes of immunotherapy. In this study, we report that oral administration of either NaHCO3 or KNa-cit increased responses to anti-programmed cell death-1 (PD-1) antibody, an immune checkpoint inhibitor, in a murine B16 melanoma model. In addition, we report that daily oral administration of an alkalinizing agent increased blood HCO3− concentrations, corresponding to increasing the tumor pHe. Serum HCO3− concentrations also correlated with urinary HCO3− concentrations and urinary pH values. There was a clear relationship between urinary pH values and the antitumor effects of immunotherapy with anti-PD-1 antibody. Our results imply that blood HCO3− concentrations, corresponding to tumor pHe and urinary pH values, may be important factors that predict the clinical outcomes of an immunotherapeutic agent, when combined with alkalinizing agents such as NaHCO3 and KNa-cit.
著者
Taro Shimizu Yoshino Kawaguchi Hidenori Ando Yu Ishima Tatsuhiro Ishida
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.70, no.5, pp.341-350, 2022-05-01 (Released:2022-05-01)
参考文献数
110
被引用文献数
2

Vaccines have contributed to the prevention of infectious diseases for a long time. Pathogen-derived antigens and adjuvants in vaccine formulations stimulate immune cells to elicit humoral and cellular immune responses against pathogens. Achieving highly immune responses with decreased adverse effects requires the development of a system that can deliver antigens to specific immune cells. Dendritic cells (DCs) are well-known professional antigen presenting cells (APCs) that initiate acquired immune responses by presenting antigens to T cells. Accordingly, DC-targeted vaccines have been investigated and applied in clinical trials for the treatment of infectious diseases and for chronic diseases such as cancers. In addition to DCs, B lymphocytes are regarded as professional APCs despite their primary role in humoral immunity. Therefore, B cell-targeted vaccines are also expected to elicit both humoral and cellular immune responses. In this review we summarize the basic functions of DCs and B cells as APCs. We also provide information on DC and B cell targeted vaccines in preclinical and clinical settings. Finally, we introduce our novel antigen delivery system that targets splenic marginal zone B cells and the ability of this system to act as a novel vaccine that elicits both humoral and cellular immune responses.
著者
Hidenori Ando Kiyoshi Eshima Tatsuhiro Ishida
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.44, no.2, pp.266-270, 2021-02-01 (Released:2021-02-01)
参考文献数
29
被引用文献数
13

Extracellular pH (pHe) of tumor cells is characteristic of tumor microenvironment (TME). Acidic TME impairs the responses of tumors to some anti-cancer chemotherapies. In this study, we showed that daily oral dosing of sodium potassium citrate (K/Na citrate) increased blood HCO3− concentrations, corresponding to increase of HCO3− concentrations and pHs in urine, and neutralized the tumor pHe. Neutralization of acidic TME by alkaline substance like HCO3−, an active metabolite of K/Na citrate, well potentiated the therapeutic effect of anticancer agent TS-1®, an orally active 5-fuluoro-uracil derivative, in Panc-1 pancreatic cancer-xenograft murine model. Neutralization of acidic TME by using an alkaline K/Na citrate is a smart approach for enhancement of the therapeutic effects of anticancer agents for pancreatic cancer in the end stage.