She says the chimpanzee tissue showed a severe loss of immune system cells.

VOA: special.2009.09.08

Again, in the context of a specific tissue site, in this case it's the nervous system.

当然又是放在某种组织当中来说,这次是在神经系统

耶鲁公开课 - 生物医学工程探索课程节选

This approach has the advantage that the tissue has a functioning system of blood vessels to deliver nutrients, so it should be possible to grow tissue cultures more than a millimetre thick the current limit.

ECONOMIST: Monitor

Could patients have themselves cloned in order to harvest cells from a genetically-identical embryo, gaining a donor and avoiding the major problem of transplant surgery: rejection of foreign tissue by the immune system?

CNN: GROWN TO ORDER

"This is a stem cell that is generated by the body's own tissue so the immune system does not recognise it and they can get any place they want without being attacked, " said Prof Rambukkana.

BBC: Leprosy bacteria use 'biological alchemy'