Table 3.
Summary of studies evaluating response to apoptosis by PNH cells.
| Manuscript | Model | Condition Tested | Main Findings |
|---|---|---|---|
| Brodsky et al., 1997 (68) | Comparison of CD59+ and CD59- granulocytes from PNH patients (n=4), progenitors (n=2), and B lymphoblastoid cell lines (n=2). | Survival of cells in serum-free media over 24-72 hours (all cells), resistance to radiation (B cell lines). | GPI (-) cells had improved survival. |
| Horikawa et al., 1997 (65) | Unsorted peripheral blood granulocytes and lymphocytes from patients with PNH (n=11), AA (n=13), MDS (n=12) and healthy controls (n=20). CD34+ cells from PNH patients (n=8). | Induction of apoptosis using anti-Fas antibody in granulocytes and lymphocytes. Induction of apoptosis in CD34+ cells with 4 day pretreatment with IFN- γ, TNF-α, followed by anti-Fas antibody. | Unsorted granulocytes from patients (PNH, AA, and MDS) were resistant to apoptosis; there was no correlation between apoptosis resistance and clone size (including clones 10%). BM CD34+ cells from PNH patients (and MDS patients) had increased resistance to apoptosis compared to controls. |
| Ware et al., 1998 (70) | Granulocytes from PNH patients (n=26) and healthy controls (n=20); GPI (-) lymphoblastoid B cell line and cell line corrected for PIGA. | Rate of apoptosis after serum starvation (granulocytes), and serum starvation, γ-radiation and anti-Fas antibody (cell lines). | Apoptosis rate in response to serum starvation was lower in granulocytes of PNH patients compared to controls. There were no differences in Fas antigen expression. Apoptosis rate did not correlate with PNH clone size. There were no differences in apoptosis of GPI (-) and GPI (+) B lymphoblastoid lines after serum starvation, γ-radiation, and anti-Fas antibody treatment. |
| Chen R et al., 2000 (73) | Comparison of CD59+ and CD59- CD34+ progenitors from PNH patients and healthy controls in liquid culture. | Cell growth and differentiation capacity. | GPI (+) cells from PNH patients had worse growth compared to GPI (-) cells and compared to CD34+ cells from controls, accompanied by higher expression of CD95 (Fas receptor) and higher sensitivity to Fas antibody treatment. |
| Chen G et al., 2002 (72) | Comparison of GPI (-) and GPI (+) CD34+ progenitors from PNH patients and healthy controls. | Growth in liquid culture and methylcellulose assays, apoptotic markers. | GPI (-) cells produced more progenitors and outcompeted GPI (+) cells in mixing experiments; however, this was not due to increased proliferation. Instead, GPI (+) cells had more apoptotic cells and higher Fas expression. After removing apoptotic cells, the growth of GPI (+) and GPI (-) cells was similar. |
| Kulkarni et al., 2002 (71) | Comparison of apoptosis sensitivity of GPI (+) and GPI (-) cells (thymocytes, granulocytes, and hematopoietic progenitor cells in Fes-Cre and EIIa Cre Piga-LoxP mouse model of PNH | Apoptosis in response to exposures to γ-irradiation, dexamethasone, etoposide, and anti-Fas antibody, and whole body γ-irradiation of mice. | No differences in apoptosis rates in GPI (-) and GPI (+) cells in response to various apoptotic stimuli. |
| Ismail et al., 2003 (67) | CD34+ cells from PNH patients (n=10) and healthy controls (n=18) | Assessment of viability, Fas expression in GPI (+) and GPI (-) CD34+ cells from the same patients | The viability of CD34+ cells in PNH patients was lower than in healthy controls, which was predominantly due to the GPI (+) cell subset. GPI (+) cells had higher expression of Fas antigen than GPI (-) cells. |
| Yamamoto et al., 2002 (77) | Unsorted granulocytes from PNH patients (n=5) compared to granulocytes from healthy volunteers (n=5). | The proportion of apoptotic cells, Fas antigen expression, and caspase-3 activity in unsorted granulocytes of PNH patients versus controls. | No differences in rates of apoptosis, Fas antigen expression, or Caspase-3 activity in PNH vs. control granulocytes. |
| Chen et al., 2005 (74) | Gene expression analysis of pooled GPI (-) and GPI (+) fractions of CD34+ progenitors from PNH patients, and CD34+ patients from controls | Gene expression | Gene expression of GPI (-) progenitors from PNH patients was similar to progenitors in controls, while GPI (+) progenitors from patients had upregulation of apoptotic proteins and other changes. |
| Savage et al., 2008 (66) | CD34+ progenitors from PNH patients (n=6) and healthy controls. Inducible PIGA-mutated TF1 cell line. | Assessment of apoptosis after induction with TNF-alpha, γ-radiation. Evaluation of cytotoxicity from allogeneic PBMCs and NK92 cell line. | CD34+ GPI (-) cells were more resistant to autologous cell-mediated killing, as well as allogeneic cell-mediated killing. Lower cytotoxicity from allogeneic PBMCs or NK92 cells in GPI (-) TF1 cells, compared to GPI(+) TF1 cells. Lower apoptosis induction of GPI (-) TF1 in response to TNFa or gamma-irradiation. |
| Kunyaboon et al., 2012 (75) | Comparison of CD59+ and CD59- granulocytes from PNH patient (n=15), and controls (n=33). | Apoptotic rate after 0-4 hours culture in the presence and absence of mononuclear cells or autologous CD8+ cells. | GPI (+) granulocytes had a higher proportion of apoptotic cells than GPI (-) granulocytes at 0 and 4 hours of culture. Co-culture with mononuclear cells increased the differential between apoptotic fractions in GPI (+) and GPI (-) cells. Percent apoptotic GPI(+) cells in PNH patients was higher than in healthy controls. |