Letter from Robert E. Akins to Marshall W. Nirenberg
Akins requests cell lines for a research project in the Nemours Children's Clinic at the Alfred I. Dupont Institute on
the differentiation and maintenance of muscular tissues and neuromuscular interactions. Akins provides a summary of research
findings and details the plans for using Nirenberg's cell line.
I am writing to request some NG108-15 cells for a research project that is commencing in our lab. We are interested in the
role of heme metabolism in the differentiation and maintenance of muscular tissues especially if it has a role in neuro/muscular
As you know, heme catabolism has been implicated in neuronal communication (Verma, et al., 1993). The enzymatic activity of
heme oxygenase (with the release of CO, biliverdin IX, and iron) may serve as a retrograde signaling mechanism among neurons,
and heme catabolism has been implicated in long term potentiation (Zhuo, et al., 1993; Stevens and Wang, 1993), the modulation
of cGMP levels in neurons (Vincent et al., 1994), neurofibrillary pathology in Alzheimer's patients (Smith et al., 1994),
as well as carotid body chemoreception (Prabhakar, et al., 1995). In addition, the direct addition of hemin to cultured neuronal
cells (Neuro 2a, neuroblastoma cells) has been shown to induce rapid neurite outgrowth (Ishii and Maniatis, 1978).
We wish to investigate the possibility that hemin affects NG108-15 differentiation through the activity of heme oxygenase;
further, we wish to determine whether the products of heme catabolism are involved in neuronal differentiation. We plan to
compare cellular proliferative activity with measures of cellular differentiation (expression of both choline acetyl transferase
and monosialyl-ganglioside, GM2). The effects of hemin and heme oxygenase inhibitors on the proliferation and differentiation
of NG108-15 cells will indicate the involvement of heme catabolism in neurite outgrowth in cholinergic neurons. In addition,
we will examine the role of heme catabolism in the establishment and maintenance of neuromuscular junctions using co-cultures
of NG108-15 cells with cardiac or skeletal muscle cells.
If possible, please send a vial of NG108-15 cells to me at the address given below. Also, please indicate the formulation
of the medium which is currently used to propagate the cells as well as what you would consider to be an appropriate "splitting"
ratio for propagation of the cells.