Osborn T W
Tubercle. 1979 Jun;60(2):83-90. doi: 10.1016/0041-3879(79)90040-0.
To follow an earlier study of the effects on BCG of deep subculture in liquid media, transfers on the surface of Löwenstein-Jensen and Sauton's media have been made. When a vaccine preparation that yields on culture 99+% of spreading-type colonies, with a small minority of non-spreading forms, is transferred on Löwenstein-Jensen medium, the minority population can be readily selected out. Growth of BCG on this medium is not homogeneous, and the selection of either the minority or majority populations appears fortuitous, whereas it was previously demonstrated that deep subculture in Dubos medium tends to favour selection of a minority yielding non-spreading colonies. When such a minority population has been favoured during transfer on Löwenstein-Jensen medium, subsequent subculture in Dubos medium usually accentuates the effect. Subculture as a surface pellicle on Sauton's medium has a powerful effect in reducing the relative size of a minority population yielding non-spreading colonies, and thereafter maintaining 99+% of spreading forms. The relationship between transfers on Löwenstein-Jensen and Sauton's media and those on potato-Sauton medium is briefly discussed.
为了跟进早期关于液体培养基深层传代对卡介苗影响的研究，已在罗-琴培养基和苏通培养基表面进行了传代操作。当一种在培养时产生99%以上扩散型菌落且少数为非扩散型菌落的疫苗制剂接种到罗-琴培养基上时，少数群体很容易被筛选出来。卡介苗在这种培养基上的生长并不均匀，选择少数群体或多数群体似乎是偶然的，而之前的研究表明，在杜博斯培养基中进行深层传代往往有利于选择产生非扩散型菌落的少数群体。当在罗-琴培养基上传代时少数群体占优势时，随后在杜博斯培养基中传代通常会增强这种效果。在苏通培养基表面形成菌膜传代，对减少产生非扩散型菌落的少数群体的相对比例有显著效果，并能使99%以上的菌落保持扩散型。本文简要讨论了在罗-琴培养基和苏通培养基上传代与在马铃薯-苏通培养基上传代之间的关系。
