The Intravenous Route of Injection Optimizes Engraftment and Survival in the Murine Model of In Utero Hematopoietic Cell Transplantation

Abstract

In utero hematopoietic cell transplantation (IUHCT) has the potential to treat a number of congenital hematologic disorders. Clinical application is limited by low levels of donor engraftment. Techniques that optimize donor cell delivery to the fetal liver (FL), the hematopoietic organ at the time of IUHCT, have the potential to enhance engraftment and the clinical success of IUHCT. We compared the 3 clinically applicable routes of injection (intravenous [i.v.], intraperitoneal [i.p.], and intrahepatic [i.h.]) and assessed short- and long-term donor cell engraftment and fetal survival in the murine model of IUHCT. We hypothesized that the i.v. route would promote direct donor cell homing to the FL, resulting in increased engraftment and allowing for larger injectate volumes without increased fetal mortality. We demonstrate that the i.v. route results in (1) rapid diffuse donor cell population of the FL compared with delayed diffuse engraftment after the i.p. and i.h. routes; (2) higher FL and spleen engraftment at early prenatal time points; (3) enhanced stable long-term peripheral blood donor cell engraftment; and (4) improved survival at higher injectate volumes, allowing for higher donor cell doses and increased long-term engraftment. These findings support the use of an i.v. route for clinical protocols of IUHCT.

In Utero Transplantation of Expanded Autologous Amniotic Fluid Stem Cells Results in Long-Term Hematopoietic Engraftment

“…In particular, 100% of animals receiving intravenous IUT of congenic 10 4 fresh or cultured AFSCs showed stable hematopoietic macrochimerism for up to 6 months, with engraftment in blood and BM exceeding 20%. This remarkable engraftment potential may also be related to the intravenous injection technique which is superior to previously described intraperitoneal delivery and is more applicable to possible clinical translation . This is also demonstrated by our recently published preliminary study in which intraperitoneal IUT of 10 4 congenic AFSCs per fetus resulted in long‐term hematopoietic engraftment only of around 10%, which is approximately half to that achieved in the present study using intravenous IUT .…”

“…Intravenous IUT was performed at E14 as previously described (see Supporting Information Methods) . Half of the surviving injected offspring in the allogenic group were nursed at birth by naive (noninjected) surrogate mothers in order to exclude transfer of maternal allo‐antibodies through breast milk .…”

“…Experimentally, engraftment of donor cells after IUT can be accomplished across full major histocompatibility complex (MHC) barriers under specific circumstances in both murine and large animal models . In the murine model of allogenic IUT, we and others have shown that successful engraftment of adult bone marrow (BM) cells requires effective delivery of a relatively large dose of cells within a specific gestational age time window to achieve tolerance . On the contrary, highly enriched HSCs do not engraft even in high doses , suggesting that, in the BM, there are cell populations other than the HSCs required for successful antigen presentation in the fetal thymus.…”

Gene Editing and Genetic Lung Disease. Basic Research Meets Therapeutic Application

“…Therapeutic intervention in the fetal period may induce immune tolerance and improve efficiency. Finally, prenatal application is feasible via the intraamniotic, vitelline vein, or by fetal intratracheal injection (48)(49)(50)(51). The presence of fetal breathing movements combined with direct contact between the developing airways and amniotic fluid suggests that CRISPR/Cas9 administered via the intraamniotic route could reach the lung epithelium.…”

In Utero Stem Cell Transplantation: Potential Therapeutic Application for Muscle Diseases

“…They were also able to transplant allogeneic skin grafts onto the chimeric mice and observe varying degrees of tolerance towards the grafts. Further studies have shown that the mode of injection [31] is also important for improving engraftment in IUT-HSCs. IUT-HSCs have also been shown to be successful in dogs [32], sheep [33], and monkeys [34, 35].…”