1. Study for tobacco smoke
Cigarette smoke is a major risk factor for pulmonary diseases. Alveolar macrophages (AM) phagocytize microorganisms, produce reactive oxygen species (ROS) and play an important role in immunological surveillance for the lung. In previous studies, we demonstrated tobacco smoking inhibits immune functions in AM. However, the mechanism of inhibition of immune function in AM is not well defined. In the aim of our study, we are investigating the suppressive mechanism of immune functions in AM associated with DNA damage by cigarette smoke exposure.

Cigarette smoke

Cigarette smoke (CS) consists of mainstream smoke, sidestream smoke, growing smoke, diffusion smoke, effusion smoke, smoldering smoke and blowing smoke, which are exhaled by a smoker.About 6000 kinds of chemical substances are contained in the cigarette smoke, and it is separated from a gas phase and  a particles phase by the condition of the material. These contain many kind of carcinogens, injury materials of epithelial cells of lung
Research Overview
We are focusing on cigarette smoke, which is currently attracting attentions as an environmental problem, hence are investigating to elucidate the effect of smoking on the relationship between smoke and pulmonary immune cells, particulary alveolar macrophages, and pulmonary epithelial cells. Smoking has been shown to to increase production of active oxygen by alveolar macrophages, which induce DNA damage in these cells, and it has also been demonstrated that their immune functions such as antigen presentation and cytokine production are impaired. It has been suggested that these inhibitions in immune functions are related to the incidence of smoking-related pulmonary epithelial cancer and tumor cell proliferation, and we are investigating this relationship and gmaking a science for smoking.h Since the fact that immune functions are suppressed by smoking and tumor growth, we are also investigating the mechanisms whereby immunoenhancing substances may act to restore suppressed immune functions.

Non-smoked mice

Smoked mice


Wellcome to Takeuchi Lab.

Research Projects

Exposure of main stream cigarette smoke to mice
2. Study for Natural products
Jungle honey (JH) is collected from timber and blossom by wild honey bees that live in the tropical forest of Nigeria. This is used as traditional medicine for cold, skin inflammation and burn wound but not only health care. However, the effect of Jungle honey on immunomodulatory activity is not yet found clearly. We have previously reported the effect of natural components on immune system. Therefore, we are investigating the effect of jungle honey on immune system and anti-tumor activity using mice.
(2) Agaricus Blazei Murill
Agaricus blazei Murill (ABM) has been traditionally used as medicine in Brazil. ABM has been reported for anti-tumor activity and immune activity. It is unclear how ABM extract activates the immune system and anti-tumor activity. We have demonstrated that extract of Agaricus blazei Murill (ABM) activated immune functions in mice. However, the mechanism of the activity of immune functions and ant-tumor activity by ABM is not well defined. Therefore, we are focusing on immune cells functions associated with anti-tumor activity by ABM hot water extract and its characterization of effective component.

Agaricus blazei Murill that belong to the basidiomycetes can grow under special weather condition( daytime 35 , night 20-25) and humidity. Although it is generally accepted that Agaricus blazei Murill possess anti-tumor activity, the detail of immune activity is unclear.

Agaricus blazei Murill
(1) Jungle honey

Natural products are known to have biological activity, and we have previously investigated the effect of natural products on immune function.. Honey contains various vitamins, minerals and amino acids as well as glucose and fructose and is popular as a natural food.. There is a wide variety of honey (Manuka honey, Pasture honey, Jelly bush honey and Jungle honey, etc.), and the varieties are due to components of the flower sources. One variety, Jungle honey, is collected from timber and blossom by wild honey bees that live in the tropical forest of Nigeria.
The jungle honey is produced by the African wild bees (Apis mellifera adansonii) in the virgin forest of the Nsukka district, Enugu state of Nigeria. The bees usually have their nests (the honey combs) inside the hollow of tree trunks. Organic agriculture methods are generally practiced in and around the forest areas. The main harvest period for jungle honey is usually between January -April. The harvest time is during the night or very early morning, when the bees activities are low.

Jungle honey

1)     Pentaclethra macrophyllaiUgba)

2)     Parinari excelsa (Inyi)

3)     Vitex doniana (Uchakiri )

4)     Dialium guineense (Icheku)

5)     Chrysophyllum albidum ( Udara)

6)     Irvingia gabonensis ( Ogbono)

7)     Mangifera indica (Mango)

8)     Treculia Africana (Ukwa)

9)     Elaeis guineensis( Nkwu)

10)   Raffia farinifera (Nkwo)

Some trees/plants were found in the jungle honey.