Drug – bio-affecting and body treating compositions – Designated organic active ingredient containing – Peptide containing doai
Reexamination Certificate
1995-03-27
2001-01-23
Duffy, Patricia A. (Department: 1645)
Drug, bio-affecting and body treating compositions
Designated organic active ingredient containing
Peptide containing doai
C514S012200
Reexamination Certificate
active
06177402
ABSTRACT:
The present invention relates to a method for regulating neuron development, maintenance and regeneration in the central and peripheral nervous systems of a mammal and to pharmaceutical compositions comprising leukaemia inhibitory factor useful for same. The present invention is particularly useful in the treatment of developmental and cerebral anomalies and neuropathies in mammals and in particular humans.
Leukaemia Inhibitory Factor (hereinafter referred to as “LIF”) is a protein that has been purified, cloned and produced in large quantities in purified recombinant form from both
Eschericia coli
and yeast cells (International Patent Application PCT/AU88/00093). LIF was originally isolated on the basis its capacity to induce differentiation and suppression of the murine myeloid leukaemic cell line, M1. LIF has no apparent proliferative effect on normal haematopoietic cells although LIF receptors have been detected on cells of the monocyte-macrophage lineage.
The present invention arose in part from an investigation of the effects of LIF on cells of the neural crest. The neural crest is a population of precursor cells which arises from the dorsal lip of the neural tube during embryogenesis and migrates through the embryo along a complex series of pathways. After migration the crest cells give rise to a great variety of cell types including the neurons and Schwann cells of the sensory and autonomic ganglia, the enteric nervous system, adrenal medulla, melanocytes of the skin and facial mesenchyme. When studied at the population level, the crest appears to be a multipotent collection of stem cells. The extensive transplantation experiments of Le Douarin and colleagues, whereby quail neural crest were grafted into chick embryos, showed that the developmental fate of the crest cells was determined by the location of this graft in the chick embryo (1). This not only indicated that the full developmental repertoire of the crest is contained in the different subpopulations of grafted crest cells, but also that environmental factors play a major role in the final differentiated phenotype of the cells.
In the last decade it has become increasingly clear that the neural crest contains subpopulations of cells which are already committed to particular developmental pathways (2,3). However, it is also clear that the differentiation of these cells is determined by environmental factors.
A number of soluble trophic factors have been shown to act as survival agents for neural crest derived neurons, but none of these have been shown to act directly on the neuronal precursor cells within the neural crest. These factors include nerve growth factor (NGF; 4), brain-derived neurotrophic factor (BDNF; 5), ciliary neurotrophic factor (CNTF; 6) and the fibroblast growth factors (FGF's; see 5).
In work leading up to the present invention, experiments were conducted to locate an agent having direct effect on the precursor populations of the neural crest. In accordance with the present invention, it has been surprisingly discovered that neural crest cells differentiate into fully mature neurons in the presence of LIF. This effect is titratable and occurs in the absence of proliferation of neuronal precursor cells. Furthermore, the effect of LIF on the differentiation of neural crest cells into neurons extends to the stimulation of the differentiation of precursor cells in embryonic dorsal root ganglia into mature sensory neurons.
Accordingly, one aspect of the present invention contemplates a method for regulating neuron development and/or maintenance and/or regeneration in a mammal comprising administering to said mammal an effective amount of leukaemia inhibitory factor (LIF) for a time and under conditions sufficient to permit the differentiation and/or maintenance and/or regeneration of neural precursor cells into neurons.
Another aspect of the present invention relates to a method for enhancing and/or stimulating and/or maintaining and/or regenerating the formation and/or survival of neurons in the central nervous system of a mammal which comprises administering to said mammal an effective amount of LIF for a time and under conditions sufficient to effect an increase in and/or to maintain the number of neurons in the central nervous system.
In one embodiment, the LIF enhances, stimulates, maintains (i.e. promotes survival) and/or regenerates immature neurons.
Yet another aspect of the present invention relates to a method for enhancing, stimulating and/or maintaining the formation and/or survival of sensory neurons, for example sensory neurons, of the peripheral nervous system of a mammal which comprises administering to said mammal an effective amount of LIF for a time and under conditions sufficient to effect an increase in and/or to maintain the number of neurons in the peripheral nervous system. By “LIF” as used herein is meant to include naturally occurring, recombinant and synthetic LIF comprising the naturally occurring amino acid sequence or any single or multiple amino acid substitutions, deletions and/or additions therein including single or multiple substitutions, deletions and/or additions to any molecules associated with LIF such as carbohydrate, lipid and/or peptide moieties. Accordingly, the term “LIF” as used herein contemplates naturally occurring LIF and LIF-like polypeptides which include mutants, derivatives, homologues and analogues of LIF. Regardless of the LIF molecule used, however, the only requirement is that it can assist in regulating neuron development and/or maintenance and/or regeneration in a mammal. In a preferred embodiment the mammal is human and the LIF is of human origin or from a different mammal but which still has activity in a human. Hence, the source of LIF and the mammal to be treated may be homologous, i.e. from the same mammal or may be heterologous, i.e. from a different mammal. In some circumstances, the mammal to be treated may itself be used to isolate the LIF for use in the method of the present invention.
By “regulating neuron development, maintenance and regeneration” as used herein is meant to include stimulating, enhancing and/or maintaining the formation and/or survival of neurons in the central and peripheral nervous systems of a mammal. It also includes the ability of said factor to assist the regeneration of properties associated with neuronal function following damage caused by disease or trauma. It is also includes stimulating, enhancing, maintaining and/or regenerating those properties associated with neurons such as, but not limited to, neurotronsmitter type, receptor type and other features associated with this phenotype. In particular, LIF has been shown herein to induce, stimulate, enhance, maintain and/or regenerate the differentiation of neural crest cells into fully mature neurons. This effect is titratable and occurs in the absence of proliferation of neuronal precursor cells. The effect of LIF also extends to the stimulation of the differentiation of precursor cells in embryonic dorsal root ganglia (DRG) into mature sensory neurons. The sensory neurons of the peripheral nervous system are derived from precursor cells in the embryonic neural crest. After crest migration, these precursor cells aggregate into the DRG and then differentiate into mature sensory neurons. The survival of sensory neurons has been shown to be dependent on two characterised growth factors, nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) and other undefined factors at critical stages during development. However, nothing is known about the identity of factors which might stimulate the differentiation of the sensory precursor cells. It was, therefore, surprisingly found in accordance with the present invention that LIF stimulated the differentiation of precursor cells in the embryonic DRG into mature sensory neurons and that LIF acted as a survival factor for these neurons throughout embryogenesis and into postnatal life.
LIF also affects the central nervous system. The early steps in the development of the central nervous syste
Bartlett Perry
Murphy Mark
Amrad Corporation, Ltd.
Duffy Patricia A.
Scully Scott Murphy & Presser
LandOfFree
Method for regulating neuron development and maintenance does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for regulating neuron development and maintenance, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for regulating neuron development and maintenance will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2471071