Immunobiology of naïve and genetically modified HLA-class-I-knockdown human embryonic stem cells

Abstract

KD was followed by flow cytometry and showed levels between 1% and 12% of those of naïve hESC between days 7 and 42 (means ± s.e.m.). (b) A total of 10 6 hESCs or hESC KD were transplanted into the gastrocnemius muscle of either immunocompetent Balb/c or severely immunocompromised SCID-beige mice. All ten Balb/c mice rapidly rejected the hESC transplants, whereas the cells survived in ten SCID-beige recipients. Rejection of hESC KD was markedly attenuated and four out of ten hESC KD grafts achieved long-term survival. 4128 Author Correction The first author apologises for these errors.Immunobiology of naïve and genetically modified HLA-class-I-knockdown human embryonic stem cells SummaryHuman embryonic stem cells (hESCs) can serve as a universal cell source for emerging cell or tissue replacement strategies, but immune rejection of hESC derivatives remains an unsolved problem. Here, we sought to describe the mechanisms of rejection for naïve hESCs and upon HLA class I (HLA I) knockdown (hESC KD ). hESCs were HLA I-positive but negative for HLA II and co-stimulatory molecules. Transplantation of naïve hESC into immunocompetent Balb/c mice induced substantial T helper cell 1 and 2 (Th1 and Th2) responses with rapid cell death, but hESCs survived in immunodeficient SCID-beige recipients. Histology revealed mainly macrophages and T cells, but only scattered natural killer (NK) cells. A surge of hESC-specific antibodies against hESC class I, but not class II antigens, was observed. Using HLA I RNA interference and intrabody technology, HLA I surface expression of hESC KD was 88%-99% reduced. T cell activation after hESC KD transplantation into Balb/c was significantly diminished, antibody production was substantially alleviated, the levels of graft-infiltrating immune cells were reduced and the survival of hESC KD was prolonged. Because of their very low expression of stimulatory NK ligands, NK-susceptibility of naïve hESCs and hESC KD was negligible. Thus, HLA I recognition by T cells seems to be the primary mechanism of hESC recognition, and T cells, macrophages and hESC-specific antibodies participate in hESC killing.

Human pluripotent stem cells: Prospects and challenges as a source of cardiomyocytes for in vitro modeling and cell-based cardiac repair

“…The induction of immune tolerance via the transplantation of human ESC-derived dendritic cells has also been suggested as a possibility [188]. Another strategy to evade T-cell activation is through the knockdown of HLA-class I proteins as shown with human ESC xenotransplants into mice [189]. Lu and colleagues disrupted β-2 microglobulin in human ESCs and generated a cell line that has impaired surface expression of HLA-class I proteins [190].…”

Immunogenicity of Pluripotent Stem Cells and Their Derivatives

“…Manipulation of HLA expression on stem cells has recently shown promise as a strategy for generating hypoimmunogenic grafts. 41 The same strategy has been previously used to facilitate transplantation of hematopoietic stem cells (HSCs). 42 The clinical applicability of this strategy, however, remains questionable, as it requires genetic manipulation to knock down a gene, and may lead to the introduction of genetic variations.…”

Minimizing the risk of allo-sensitization to optimize the benefit of allogeneic cardiac-derived stem/progenitor cells

“…Furthermore, xenotransplantation of human embryonic stem cells (hESC) induces a rapid surge of DSA-HLA-I that contribute to immune rejection, whereas HLA-I knockdown remarkably alleviates antibody production and prolongs the survival of hESC24. Although the mechanisms involved in humoral allo-rejection of stem cells are still unknown, studies in animal model suggested that CDC and ADCC might be responsible for stem cell elimination in vivo, as in the case of organ or cell transplantations25.…”