A knock-out model of paroxysmal nocturnal hemoglobinuria: Pig-a(-) hematopoiesis is reconstituted following intercellular transfer of GPI-anchored proteins.

Dunn, Daniel E.; Ji, Yu; Nagarajan, Shanmugam; Devetten, Marcel P.; Weichold, Frank F.; Medof, M. Edward; Young, Neal S.; Liu, J. M.

doi:10.1073/pnas.93.15.7938

Cited by 99 publications

(59 citation statements)

References 48 publications

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“…Our finding that pig-aϪ EBs undergo hematopoietic differentiation is in apparent contrast with the finding reported by Dunn et al (41). It could be that the only clone they tested was defective like our clone 108 which had probably lost its totipotency since it failed not only to undergo hematopoietic differentiation in EBs (Table III), but also to produce chimeric mice (Table I).…”

Section: Pig-aϫ Es Cells Contribute In Vivo To Erythro-myelo-and Lympcontrasting

confidence: 57%

“…GATA4Ϫ/Ϫ EBs are unable to form the visceral endoderm, suggesting that this structure is essential for organizing and retaining blood islands in suspension culture. Interestingly, pig-aϪ EBs formed in liquid culture resemble to some extent GATA4Ϫ/Ϫ EBs in that they also fail to form cystic cavities (our observation and [41]). Thus, pig-aϪ EBs, being unable to form visceral endoderm, may simply lose their hematopoietic cells into the medium.…”

Section: Pig-aϫ Es Cells Contribute In Vivo To Erythro-myelo-and Lympmentioning

confidence: 93%

“…Thus, pig-aϪ EBs, being unable to form visceral endoderm, may simply lose their hematopoietic cells into the medium. This would also explain why hematopoietic differentiation is restored in pig-aϪ/pig-aϩ chimeric EBs in which visceral endoderm can be contributed by the normal ES cells (41).…”

Section: Pig-aϫ Es Cells Contribute In Vivo To Erythro-myelo-and Lympmentioning

confidence: 99%

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Murine embryonic stem cells without pig-a gene activity are competent for hematopoiesis with the PNH phenotype but not for clonal expansion.

Rosti¹,

Tremml²,

Soares³

et al. 1997

J. Clin. Invest.

131

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Paroxysmal nocturnal hemoglobinuria (PNH) develops in patients who have had a somatic mutation in the X-linked PIG-A gene in a hematopoietic stem cell; as a result, a proportion of blood cells are deficient in all glycosyl phosphatidylinositol (GPI)-anchored proteins. Although the PIG-A mutation explains the phenotype of PNH cells, the mechanism enabling the PNH stem cell to expand is not clear. To examine this growth behavior, and to investigate the role of GPI-linked proteins in hematopoietic differentiation, we have inactivated the pig-a gene by homologous recombination in mouse embryonic stem (ES) cells. In mouse chimeras, pig-a Ϫ ES cells were able to contribute to hematopoiesis and to differentiate into mature red cells, granulocytes, and lymphocytes with the PNH phenotype. The proportion of PNH red cells was substantial in the fetus, but decreased rapidly after birth. Likewise, PNH granulocytes could only be demonstrated in the young mouse. In contrast, the percentage of lymphocytes deficient in GPI-linked proteins was more stable. In vitro, pig-a Ϫ ES cells were able to form pig-a Ϫ embryoid bodies and to undergo hematopoietic (erythroid and myeloid) differentiation. The number and the percentage of pig-a Ϫ embryoid bodies with hematopoietic differentiation, however, were significantly lower when compared with wild-type embryoid bodies. Our findings demonstrate that murine ES cells with a nonfunctional pig-a gene are competent for hematopoiesis, and give rise to blood cells with the PNH phenotype. pig-a inactivation on its own, however, does not confer a proliferative advantage to the hematopoietic stem cell. This provides direct evidence for the notion that some additional factor(s) are needed for the expansion of the mutant clone in patients with PNH. ( J.

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Section: Pig-aϫ Es Cells Contribute In Vivo To Erythro-myelo-and Lympcontrasting

confidence: 57%

Section: Pig-aϫ Es Cells Contribute In Vivo To Erythro-myelo-and Lympmentioning

confidence: 93%

Section: Pig-aϫ Es Cells Contribute In Vivo To Erythro-myelo-and Lympmentioning

confidence: 99%

See 1 more Smart Citation

Murine embryonic stem cells without pig-a gene activity are competent for hematopoiesis with the PNH phenotype but not for clonal expansion.

Rosti¹,

Tremml²,

Soares³

et al. 1997

J. Clin. Invest.

131

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show abstract

“…11,30 Moreover, PIGA mutant cells do not expand in the murine Piga knockout models. [31][32][33] Of clinical note, blood cells with PNH phenotype (GPI-deficient or GPI Ϫ cells) are frequently detected in patients with BM failure syndromes such as aplastic anemia 34,35 and MDS. 13 As expected, some of the patients really develop hemolytic PNH.…”

Section: Introductionmentioning

confidence: 99%

Immunoselection by natural killer cells of PIGA mutant cells missing stress-inducible ULBP

Hanaoka

Kawaguchi

Horikawa

et al. 2006

Blood

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The mechanism by which paroxysmal nocturnal hemoglobinuria (PNH) clones expand is unknown. PNH clones harbor PIGA mutations and do not synthesize glycosylphosphatidylinositol (GPI), resulting in deficiency of GPI-linked membrane proteins. GPI-deficient blood cells often expand in patients with aplastic anemia who sustain immune-mediated marrow injury putatively induced by cytotoxic cells, hence suggesting that the injury allows PNH clones to expand selectively. We previously reported that leukemic K562 cells preferentially survived natural killer (NK) cell-mediated cytotoxicity in vitro when they acquired PIGA mutations. We herein show that the survival is ascribable to the deficiency of stress-inducible GPI-linked membrane proteins ULBP1 and ULBP2, which activate NK and T cells. The ULBPs were detected on GPI-expressing but not on GPI-deficient K562 cells. IntroductionParoxysmal nocturnal hemoglobinuria (PNH) is an acquired stem cell disorder of clonal nature characterized by intravascular hemolysis, venous thrombosis, bone marrow (BM) dysfunction, and infrequent development of leukemia. [1][2][3][4] In the last 2 decades, virtually the entire mechanism leading to PNH hemolysis has been elucidated. [5][6][7][8] PNH stem cells acquire PIGA mutations and do not generate glycosylphosphatidylinositol (GPI), resulting in a deficiency of a series of GPI-linked membrane proteins, including complement regulatory molecules such as decay-accelerating factor (DAF) and CD59. PNH cells are then vulnerable to autologous complement. For example, PNH erythrocytes undergo complement-mediated hemolysis. Soon after, the molecular events leading to clinically serious hemolytic precipitation induced by infection were clarified. 9 On the other hand, more than half of patients with PNH show various cytopenias and decreased CD34 ϩ hematopoietic cells. [1][2][3][4][10][11][12] PNH closely associates with aplastic anemia and myelodysplastic syndromes (MDSs) that share BM failure and development of leukemia. 1,12,13 It has been indicated that immune-mediated BM injury underlies at least a part of the diseases. 1,12 Indeed, immunosuppressive therapy ameliorates their marrow failure. 1,12,14,15 Of interest, combination therapy with antithymocyte globulin and cyclosporine A, these immunosuppressants having individual target spectra, 16,17 gives better results than therapy with each 1 of the 2 immunosuppressants. 12,18 In general, both cytotoxic T lymphocytes (CTLs) of adaptive immunity and natural killer (NK) cells of innate immunity operate in combination rather than independently. [19][20][21][22] It is then conceivable that both cytotoxic cells exert critical roles in BM injury, 12,[23][24][25][26] although real features of the autoimmunity have not been delineated.The marked progress in understanding of PNH pathophysiology evokes the next concern about the etiology of PNH, and the mechanisms of both selective expansion of PNH clones 27 and development of leukemia. 28 Above all, we have focused on the expansion of affected cells to mani...

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“…GPI proteins can also be found in serum and other body fluids both with intact or absent GPI anchors (Landi et al 2003). Processes that release GPI-linked proteins into the medium with intact GPI anchors are reversible and it has been shown in a variety of in vitro and in vivo systems that GPI-linked proteins can be re-inserted into cell membranes (Dunn et al 1996;Kooyman et al 1995;Rifkin and Landsberger 1990;Rooney et al 1993;Rooney et al 1996;Vakeva et al 1994). Transfer has been demonstrated for CD59 from erythrocytes to endothelial cells (Kooyman et al 1995) as well as for trypanosomal variant surface glycoprotein (VSG) to erythrocytes of infected patients (Rifkin and Landsberger 1990).…”

Section: Glycosylphosphatidylinositol (Gpi) Modificationmentioning

confidence: 99%

Surface Modification of Retroviral Vectors for Gene Therapy

Metzner¹,

Dangerfield²

2011

Viral Gene Therapy

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A knock-out model of paroxysmal nocturnal hemoglobinuria: Pig-a(-) hematopoiesis is reconstituted following intercellular transfer of GPI-anchored proteins.

Abstract: We created a "knock-out"

Cited by 99 publications

References 48 publications

Murine embryonic stem cells without pig-a gene activity are competent for hematopoiesis with the PNH phenotype but not for clonal expansion.

Murine embryonic stem cells without pig-a gene activity are competent for hematopoiesis with the PNH phenotype but not for clonal expansion.

Immunoselection by natural killer cells of PIGA mutant cells missing stress-inducible ULBP

Surface Modification of Retroviral Vectors for Gene Therapy

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