Pediatric researchers have resolved an apparent contradiction in the field of prenatal cell transplantation a medical approach that holds future promise in correcting sickle cell disease and other serious congenital blood disorders. In a new study in animals, the researchers showed that the mother's immune response interferes with the offspring's earlier ability to tolerate transplanted donor cells.
The study team concludes that focusing on transplant techniques that avoid the maternal immune response may allow scientists to take advantage of fetal tolerance to achieve a long-sought goal of treating blood diseases prenatally.
While cautioning that much work must be done to understand how these animal findings apply to humans, the current findings are "surprising but reassuring," said study leader Alan W. Flake, M.D., of the Children's Center for Clinical Research at The Children's Hospital of Philadelphia.
The study appeared online August 3 in the Journal of Clinical Investigation.
For over 50 years, explained Flake, it has been a fundamental precept of immunology that a fetus tolerates foreign antigens in a window-of-opportunity period before its immune system fully develops the capacity to mount an immune response. Scientists assumed that by carefully introducing donor cells and stimulating a fetus to develop tolerance to those cells, one could set the stage for a later organ or cellular transplant that would not be rejected by a more mature immune system.
As prenatal diagnosis has continued to become available for a greater number of congenital diseases, scientists have considered the possibility of correcting blood disorders such as sickle cell disease or thalassemia. After first transplanting a small number of healthy cells in an early-stage fetus to establish tolerance, a second dose of transplanted cells later in gestation would proliferate, and treat the blood disorder before birth. Researchers use he
'/>"/>
| Contact: Rachel Salis-Silverman Salis@email.chop.edu 267-426-6063 Children's Hospital of Philadelphia Source:Eurekalert |