Other Related Information 

About Lectins		About Sugar Chains
What are lectins? Hemagglutination activity assay  How to use biotin-labeled lectin	Use as a mitogen Lectin Agarose  Lectin solubility	Functions of glycans  Glycans and disease

Usage as a mitogen 

 What is a mitogen?

Among the biological activities of lectins on cells, a groundbreaking one is their reaction with lymphocytes. When lymphocytes are cultured with a very low concentration of lectin, the lymphocytes begin to proliferate and divide. This triggering of resting lymphocytes to grow and proliferate is called mitogenic stimulation, and is an important phenomenon that is key to the body's immune response to foreign substances (antigens).

The lectins that are mainly used as mitogens are Con A, PHA-P, PHA-L4, PWM, etc., and are tested by culturing them with lymphocytes for 48 to 72 hours and measuring the increase in labeled thymidine incorporated into DNA. Many mitogenic lectins stimulate only T cells in lymphocytes and have no activity against B cells, but PWM is an exception and activates both T cells and B cells.

Mitogenic lectins can activate most activatable lymphocytes regardless of the antigen specificity of the cells, making it easy to pursue and study changes caused by cell proliferation.
1) 2) 3) 4) It has also been shown that lectins induce cytotoxic activity in T lymphocytes. The cytotoxic activity of the induced T cells is antigen non-specific, and is therefore exerted against a variety of normal and malignant cells. 5) Mitogen activation by lectins is thus a means of assessing the immune function of patients with various diseases, including AIDS, because it is easy and simple to use. It is also used to examine the effects of various immunosuppressants and immunotherapies. Recently, it has also attracted attention as a lymphocyte mitogen in LAK therapy, a cancer treatment. 6) 7)

Human lymphocyte blastogenesis test
Lymphocyte blastogenesis test is often used to measure and compare the DNA synthesis ability of peripheral blood lymphocytes of disease patients. This reaction is thought to indicate general cellular immune response ability. There are other measurement methods, such as counting the number of cells with chromosomes in fixed and stained specimens and morphological observation, but the method of measuring the incorporation of 3H-thymidine into the cell nucleus is often used because it is simple and objective.

References

1) Matsumoto, N., Toyoshima, S., Osawa, T., J. Biochem., 113, 630 (1993)
2) Thomas, L. J., et al., J. Biol. Chem., 266, 23175 (1991)
3) Yeh, E. T. H., TIGG, 4, 505 (1992) 4) Tanaka, M., Muto, N., Gohda, E., Yamamoto, I., Jpn. J. Pharmacol., 66, 451 (1994)
5) Elieser, G., TIGG, 6, 435 (1994) 6) Rosenberg, 3A., Lotze, M. T., Muul, L. M., N. Engl. J. Med., 313, 1485 (1985)
7) Nitta, T., Sato, K., Yagita, H., Okumura, K.,Ishii, S., The Lancet, 335, 368 (1990)