The rationale and potential aims of growth factor treatment in aplastic anemia

The standard treatment of aplastic anemia is allogeneic stem-cell transplantation or immunosuppressive treatment. These approaches are discussed in more detail in Chapters 10, 12 and 13 of this volume. This chapter concentrates on the use of hemopoietic growth factors in aplastic anemia. Essentially there are four possible indications for the use of growth factors in aplastic anemia:

• Growth factors could be used therapeutically with the aim of inducing remission of the disease.

• Growth factors could be used as adjuvant treatment for patients receiving concomitant immunosuppressive treatment with the aim of improving the rate and quality of remissions after immunosuppression.

• Growth factors could be used as supportive care in order to reduce the risk of infection and bleeding associated with cytopenia.

• Growth factors could be used to collect peripheral blood stem cells for allogeneic (and possibly even autologous) stem-cell transplantation.

Hemopoietic growth factors have been used in all four settings. Growth factors exert several possible effects that provide the rationale for their use in the treatment of aplastic anemia:

1. 1. a. Growth factors stimulate the proliferation and differentiation of the residual primitive hemopoietic progenitor cells in aplastic anemia (Bacigalupo et al., 1991, 1993a; Bagnara et al., 1992; Gibson et al., 1994; Scopes et al., 1995, 1996; Wodnar Filipowicz et al., 1992, 1997).

2. b. Apoptotic activity in aplastic anemia bone marrow progenitor cells is accelerated (Maciejewski et al., 1995a,b; Philpott et al., 1995). Growth factors can exert antiapoptotic activity (Adachi et al., 1993; Philpott et al., 1997) and may therefore suppress the increased apoptotic activity in the bone marrow of those with aplastic anemia.

3. […]