of protection against intruders and quenching any local disturbances. Under certain stimulatory conditions, additional members of the department can be recruited into active duty, affording a more potent protective police force. It is only under the most unusual combination of circumstances where such protective T cells are corrupted into criminal behavior that results in tissue destruction and true autoimmune disease. I hope that the readership will consider the merits (and the shortcomings) of this conceptual framework and I look forward to your thoughts and to your feedback.


I wish to especially thank Rob Fairchild, Anna Valujskikh and Charley Orosz for their helpful discussions, input and feedback.

This article is reprinted from Graft 2003; Vol. 6, No. 1:33-41, with permission from the authors.


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