[Augmentation of immune defense mechanisms of the lung by romurtide]

Muramyl dipeptide (MDP), derived from the major constituent of bacterial cell walls, can augment host defense mechanisms, and romurtide [MDP-Lys (L18)], a synthetic MDP derivative, is thought to be more potent than other MDP derivatives. Therefore, we evaluated whether romurtide can bolster the immune defense mechanisms of the lung. We compared the functions of peripheral blood leukocytes with those of broncho alveolar lavage fluid cells (BALF cell) in DA rats and in patients with lung cancer who were treated with radiation. The results indicate that romurtide can increase the antibacterial activity of BALF cells preferentially and that this adjuvant therapy can help to prevent respiratory infections.