Chapter J 



Transplantation of Autogenous and 

 Homoiogenous Tissues in Mice 



The large majority of experiments which we carried out in mice were 

 done with closely inbred strains, and exchange of tissues between 

 members of the same strain would therefore not correspond to homoio- 

 genous transplantations but to something akin to autogenous or syngenesio- 

 transplantation. Which of these two types of transplantation it resembles more 

 would depend on the degree and effects of the inbreeding. However, experi- 

 ments in which tissues are transferred from one strain to another strain would 

 be more nearly comparable to homoiogenous transplantations, although there 

 is no absolute identity of inter-strain transplantation and ordinary homoio- 

 transplantation ; in the latter there may be a somewhat greater variability in 

 the relations between the individuality differentials of host and transplant. In 

 addition to the transplantation between different strains — inter-strain trans- 

 plantation — we have also made some experiments in which tissues were ex- 

 changed between ordinary non-inbred white mice obtained from various 

 dealers. As to autogenous transplantations, these should not be affected by the 

 inbreeding and should yield the same results in closely inbred, in less closely 

 inbred, and in non-inbred strains. 



Autogenous transplantation in mice. Autogenous transplantation is in all 

 essential respects similar to this type of transplantation in rat and guinea pig. 

 The tissue remains preserved provided the injury connected with the process 

 of grafting and that due to the abnormal position of the graft have no long- 

 lasting, unfavorable effects. The changes which are observed after auto- 

 transplantation can not be due to incompatibility between the individuality 

 differentials of host and transplant, since these differentials are identical, but 

 they are due to mechanical or chemical factors of a non-specific kind, similar 

 to those which, under corresponding conditions, might also take place in non- 

 transplanted tissues. On account of vascular changes around the transplant 

 and of necrosis in the insufficiently nourished portion of the grafted tissues, 

 polymorphonuclear leucocytes may appear; lymphocytes may be attracted by 

 non-specific factors, such as foreign bodies, causing a mild degree of injury, 

 and epithelioid and giant cells may be produced. Injury or abnormal growth 

 processes in non-transplanted normal striated muscle tissue may call forth a 

 multiplication of muscle nuclei and the formation of thinner muscle fibers or 

 spindles. The same changes may take place in transplanted muscle. Dense 

 fibrous tissue tends to form around and sometimes between the living muscle 

 fibers, and, at first, some lymphocytes may accumulate between the muscle 

 fibers. But the lymphocytes were not numerous in the autotransplanted muscle 

 tissue ; they were still found at 20 days, but no longer after 30 days following 



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