Raichvarg D, Guenounou M, Brossard C, Agneray J
Infect Immun. 1981 Jul;33(1):49-53. doi: 10.1128/iai.33.1.49-53.1981.
Mild hydrolysis of Haemophilus influenzae type a lipopolysaccharide by ion exchangers yielded a lipid A extracted by chloroform. It contained phosphorus, glucosamine, and fatty acids. Myristic, palmitic, 3-hydroxymyristic, and oleic acids and two other unidentified long-chain fatty acids were found. The free lipid A was not toxic for mice at doses of up to 50 mg/kg and did not provoke a Shwartzman reaction. The Limulus test activity was positive up to 10(-12) g/ml, but the pyrogenicity in rabbits was lower than with the original lipopolysaccharide. However, the lipid A did induced a mitogenic response and polyclonal B-cell activation in mouse spleen cell cultures. Complexing lipid A with bovine serum albumin gave a nontoxic preparation which lost these immunological activities. Immunochemical studies showed that the major reactive determinants of this lipid-protein complex were altered after such a linkage. Consequently, the nontoxic and mitogenic lipid A isolated from H. influenzae type a did not exhibit all of the classical activities of lipid A preparations.
通过离子交换剂对甲型流感嗜血杆菌脂多糖进行轻度水解，得到一种可被氯仿提取的脂质A。它含有磷、葡糖胺和脂肪酸。发现其中含有肉豆蔻酸、棕榈酸、3-羟基肉豆蔻酸、油酸以及另外两种未鉴定的长链脂肪酸。游离脂质A在剂量高达50mg/kg时对小鼠无毒，也不会引发施瓦茨曼反应。鲎试剂检测活性在高达10(-12)g/ml时呈阳性，但在兔体内的致热原性低于原始脂多糖。然而，脂质A在小鼠脾细胞培养物中确实诱导了促有丝分裂反应和多克隆B细胞活化。将脂质A与牛血清白蛋白复合得到一种无毒制剂，该制剂失去了这些免疫活性。免疫化学研究表明，这种脂质-蛋白质复合物的主要反应性决定簇在这种连接后发生了改变。因此，从甲型流感嗜血杆菌中分离出的无毒且具有促有丝分裂作用的脂质A并未表现出脂质A制剂的所有经典活性。
