Muramyl dipeptide (MDP) can exert an adjuvant activity on antibody formation and cell-mediated immunity in experimental animals. Furthermore, MDP also can augment the activities of macrophages. On the basis of such observations, many researchers try to make MDP derivatives. It is not only powerful in augmenting immune responses to antigens but also in resistance against microbial infections and tumor cells. Some studies want to find MDP derivatives capable of augmenting resistance to microbial infection. In previous experiments, an MDP derivative, L18- MDP, was shown to augment the resistance to Escherichia coli infection in mice more effectively than MDP. In the present study, L18-MDP has the augmentation of resistance to infections with E. coli, Pseudomonas aeruginosa, Staphylococcuts aureus, and Candida albicans. Today, we will introduce MDP derivative — L18- MDP.

L18-MDP, a derivative of MDP, is an antibacterial agent with antibacterial activity for bacterial and fungal infections.

Firstly, L18-MDP (100 µg; s.c.; single dose) has an anti-infection effect in mice infected with Escherichia coli or Klebsiella pneumoniae. Secondly, L18-MDP (100 µg or 1000 µg; s.c., i.p., i.v. or p.o.; single dose) increases the survival rate of mice infected with Escherichia coli and improves the pathological tissue of mice infected with Listeria monocytogenes. In addition, L18-MDP (100 µg or 200 µg; s.c. or i.p.; once daily for 3 days) increases the survival rate of mice infected with Candida albicans.

In sum, L18-MDP is an antibacterial agent for bacterial and fungal infections research.


[1] Osada Y, et al. Effect of L18-MDP(Ala), a synthetic derivative of muramyl dipeptide, on nonspecific resistance of mice to microbial infections. Infect Immun. 1982;37(1):292-300.