Yl. Xue et al., Pain relief by xenograft of subarachnoid microencapsulated bovine chromaffin cells in cancer patients, PROG NAT SC, 10(12), 2000, pp. 919-924
The bovine chromaffin cells (BCC) implanted into the subarachnoid space can
release analgesic substances such as opioid peptides and catecholamines. C
linical trials have provided the evidence that the implantation of polyviny
lchloride (PVC) hollow fiber encapsulated BCC by surgery can relief the pai
n in cancer patients. In the present study, BCC were encapsulated in algina
te-polylysine-alginate (APA) microencapsules which protect the grafting of
xenogeneic cells from host immune system and allow BCC to function effectiv
ely without using immunosuppression agents. The microencapsulated BCCs (5 x
10(6)-8 x 10(6)) were transplanted into the subarachnoid space L3-5 of 17
patients who suffered from chronic cancer pain and had to have long-term ad
ministration of analgesics. The pain scores and morphine intake test showed
that microencapsulated BCC graft totally stopped the chronic pain in three
of the patients over a period of 200 days and in the other three over a pe
riod of 100 days. The results suggest that APA microencapsulated UCC xenotr
ansplantation could be a novel alternative approach to managing pain of can
cer patients.