Baboon bone-marrow xenotransplant in a patient with advanced HIV disease: case report and 8-year follow-up.
BACKGROUND
Xenotransplantation offers a solution to the shortage of organ donors and may offer resistance to human-specific pathogens. Baboons are resistant to productive infection with HIV-1. A baboon bone-marrow transplant (BMT) was performed in an attempt to reconstitute the immune system of a patient with advanced AIDS. The aims of this pilot study were to evaluate the safety of the procedure and develop an approach to prevent and monitor for xenozoonoses.


METHODS
A source animal was selected on the basis of infectious disease surveillance protocols. Baboon bone marrow, engineered to remove graft-versus-host-disease-producing mature lineages, but to retain hematopoietic stem cells and facilitating cells, was infused into the patient after nonmyeloablative conditioning. Serial clinical, virologic, immunologic, and hematologic evaluations were performed.


RESULTS
A 38-year-old male with advanced AIDS, who had failed to respond to triple-drug antiretroviral therapy, underwent baboon BMT in 1995. The patient tolerated the procedure without complication. Baboon cells were detected in the peripheral blood on days 5 and 13 after transplantation. Baboon endogenous virus (BaEV) was detected on day 5 but not subsequently. Antibody to BaEV was not detected. HIV-1 viral load declined 1.5 log and remained low until 11 months. The patient improved clinically, and no adverse events occurred. The patient is alive 8 years after the procedure.


CONCLUSIONS
Baboon BMT to treat AIDS was attempted using nonmyeloablative conditioning and resulted in transient microchimerism and clinical and virologic improvements. Long-term improvement was not achieved; however, no adverse events occurred, and no evidence of transmission of xenogeneic infections was found.
Michaels
Marian G
MG
University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA.
Kaufman
Christina
C
Volberding
Paul A
PA
Gupta
Phalguni
P
Switzer
William M
WM
Heneine
Walid
W
Sandstrom
Paul
P
Kaplan
Lawrence
L
Swift
Patrick
P
Damon
Lloyd
L
Ildstad
Suzanne T
ST
D000163:Acquired Immunodeficiency Syndrome / Q000628:therapy*; D000328:Adult; D000818:Animals; D016026:Bone Marrow Transplantation; D005500:Follow-Up Studies; D015497:HIV-1; D006801:Humans; D015182:Lymphatic Irradiation; D008297:Male; D010215:Papio; D010865:Pilot Projects; D012367:RNA, Viral / Q000097:blood; D014183:Transplantation, Heterologous
D012367:RNA, Viral