Riveau G, Parant M, Chedid L
J Leukoc Biol. 1984 Aug;36(2):111-22. doi: 10.1002/jlb.36.2.111.
Muramyl dipeptide (MDP) is a small molecular weight synthetic glycopeptide (less than 500), which has been shown to be an immunoadjuvant, and to induce a biphasic febrile response in the rabbit--probably via the release of endogenous pyrogen--accompanied by a marked leukopenia. Macromolecularization by coupling to a synthetic carrier (MW approximately or equal to 60,000) potentiates the immunostimulant properties of MDP but also its pyrogenicity. The present study demonstrates that such a conjugate induced the release of endogenous pyrogen in vivo and in vitro at lower dosage levels than free MDP. Further experiments showed that there existed several differences between free and conjugated MDP. Thus, after intravenous administration of the conjugate, the fever pattern was monophasic with a prompt defervescence and not accompanied by leukopenia at dosage levels inducing similar increase in body temperature. In addition, when fever was recorded after intracerebroventricular administration, the increase in sensitivity was much greater in the case of free MDP than of MDP-A--L.
胞壁酰二肽（MDP）是一种小分子合成糖肽（分子量小于500），已被证明是一种免疫佐剂，能在兔体内诱导双相热反应——可能是通过内源性致热原的释放——同时伴有明显的白细胞减少。与合成载体（分子量约为60,000）偶联实现大分子化可增强MDP的免疫刺激特性，但也会增强其致热性。本研究表明，这种缀合物在体内和体外以比游离MDP更低的剂量水平诱导内源性致热原的释放。进一步的实验表明，游离MDP和缀合MDP之间存在若干差异。因此，静脉注射缀合物后，发热模式为单相，退热迅速，在引起体温类似升高的剂量水平下不伴有白细胞减少。此外，当脑室内给药后记录到发热时，游离MDP比MDP-A-L的敏感性增加要大得多。
