急性运动轴索型神经病患者血清对培养脊髓运动神经元的影响

EFFECTS OF SERUM FROM A PATIENT WITH ACUTE MOTOR AXONAL NEUROPATHY ON SPINAL MOTOR NEURONS CULTURED IN VITRO

为了观察急性运动轴索型神经病(AMAN)病人血清对培养的胚胎大鼠脊髓运动神经元及其轴突的影响,直接、动态观察致病因素对轴突的损害程度。我们分离了胚胎大鼠脊髓腹侧组织,制备成细胞悬液在体外进行原代培养,应用抗非磷酸化神经微丝单克隆抗体SMI-32对培养细胞染色鉴定为运动神经元。培养6天时给予25%浓度AMAN病人血清进行干预,血清中检测有致病型空肠弯曲菌(Cj)PennerO:19型脂多糖抗体存在,正常人血清作为对照组。观察神经元胞体和突起的变化,并经Guillery Shirra及Webster法进行变性纤维染色。结果表明AMAN病人血清干预9h可引起培养运动神经元的轴突变性,嗜银性增加并染为棕黑色;干预12h,胞体开始肿胀,核偏移,胞浆内有银颗粒的沉积,最终培养神经元在16h开始死亡。对照组神经元生长无变化。我们认为AMAN病人血清中含有致病成分,可引起运动神经元轴突变性和继发性胞体改变,最终神经元死亡。推测这种损害在无补体和巨噬细胞参与下,抗PennerO:19型Cj脂多糖抗体起着重要作用。

The effect of serum from a patient with acute motor axonal neuropathy (AMAN) on cultured motor neurons was studied. The ventral spinal ventral tissue was isolated from embryonic rats and digested into dissociated cell suspention for culture in vitro. The cultured cells were stained with SMI-32, a non-phosphorylated neurofiliment marker monoclonal antibody to identify motor neurons. The 6 days' cultured cells were exposed to the AMAN patient serum in a concentration of 25%, and to the normal human serum as the control. Positive PennerO:19 Campylobacter jejuni lipopolysaccharide antibody in the AMAN serum used in this experiment had been testified. The serum-cultured motor neurons were observed morphologically and also stained by Guillery Shirra and Webster method. With this staining, degenerated nerve fibers were brown-black and normal nerve fibers were brown-yellow. At the 9th h after the AMAN serum exposure, the axon degenerated and was stained brown-black due to increased silver-phile property. At the 12th h, the neuron soma began to swell and nuclear deviation with silver granules depositing in the cytoplasm. At last, the neurons began to die from the 16th h of the exposure. However, the control motor neuroas did not show these alterations in the same period of culture. The serum of AMAN patient may be toxic to the neurite of motor neuron and thus cause axon degeneration, then soma alterations and death followed. It is suggested that Campylobacter jejuni lipopolysaccharide antibody may play an important role in this process without the participation of macrophages and complements.