NELSON J B
J Exp Med. 1957 Aug 1;106(2):179-90. doi: 10.1084/jem.106.2.179.
Pleuropneumoma-like organisms (PPLO) of the catarrhal type were isolated from the brain of a Swiss mouse during the cranial passage of mouse hepatitis virus-MHV(C). Cranial injection of the PPLO alone in Swiss and Princeton weanlings was attended by a meagre growth of the organisms in the brain, with no pathologic change. The growth of both catarrhal and conjunctival strains of PPLO in the brains of Swiss mice was greatly enhanced by the simultaneous injection of MHV(C). Rolling was not a characteristic sign prior to autopsy. Brain sections regularly showed a vigorous leukocytic response, commonly accompanied by the destruction of nerve cells in the anterior horns of the cerebrum. Injected in Princeton mice together with the virus, the organisms barely survived and were inactive. MHV(Pr) enhanced the growth and pathogenicity of PPLO in the brains of Princeton mice but failed to do so in Swiss. The behavior of PPLO in the brain was likewise affected by the presence of agar, as earlier observed by Findlay et al. In comparison with the effect of MHV, the enhancement was reduced in rate in both strains of mice and was not accompanied by outward signs of nervous disorder. Hydrocephalus which often followed injection of the PPLO-agar mixture was also produced by agar-bouillon alone.
在小鼠肝炎病毒 - MHV(C)经颅传代期间，从一只瑞士小鼠的脑中分离出了卡他型胸膜肺炎样微生物（PPLO）。单独向瑞士和普林斯顿断奶小鼠脑内注射PPLO时，脑内该微生物生长微弱，且无病理变化。同时注射MHV(C)可显著增强瑞士小鼠脑中卡他型和结膜型PPLO菌株的生长。尸检前翻滚并非特征性体征。脑切片经常显示强烈的白细胞反应，通常伴有大脑前角神经细胞的破坏。与病毒一起注射到普林斯顿小鼠体内时，这些微生物几乎无法存活且无活性。MHV(Pr)增强了PPLO在普林斯顿小鼠脑中的生长和致病性，但在瑞士小鼠中未起到这种作用。正如芬德利等人早期观察到的那样，脑内PPLO的行为同样受到琼脂存在的影响。与MHV的作用相比，两种品系小鼠中这种增强作用的速率均降低，且未伴有神经紊乱的外在体征。单独注射琼脂肉汤也会导致注射PPLO - 琼脂混合物后经常出现的脑积水。
