Purification of embryonic rat motoneurons by panning on a monoclonal antibody to the low-affinity NGF receptor

doi:10.1016/0165-0270(92)90114-S

Journal of Neuroscience Methods

Volume 44, Issue 1, August 1992, Pages 59-70

https://doi.org/10.1016/0165-0270(92)90114-S Get rights and content

Abstract

Available methods for purifying motoneurons to homogeneity from rodent spinal cord involve retrograde labelling and fluorescence-activated cell sorting, making them costly and time consuming. Motoneurons are the only neurons within the 15-day embryonic rat spinal cord to express the p75 low-affinity NGF receptor and we show that monoclonal antibody 192-IgG, which binds to the extracellular domain of p75, selectively labels a sub-population of large multipolar ventral spinal cord neurons in vitro. We have developed a bench-top panning method for purifying these motoneurons using antibody 192-IgG. Approximately 10⁵ cells/spinal cord are obtained in 2 h by this method; 95°k of them express p75 in culture. They rapidly put out neurites on laminin substrata, and their survival is enhanced by extracts of skeletal muscle. Using the panning method in conjunction with centrifugation on a 6.8% metrizamide cushion, separate populations of large and small motoneurons were obtained, each containing more than 90% neurons staining with antibody 192. The large motoneurons had choline acetyltransferase activities/cell approximately 4-fold greater than those of dissociated total spinal cells and 7-fold higher than those of the small motoneurons. These methods should be of considerable use for studies on factors affecting motoneuron survival and development and for transplantation of highly purified neuronal populations.

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Research paperPurification of embryonic rat motoneurons by panning on a monoclonal antibody to the low-affinity NGF receptor

Abstract

Neuron

Cell

Dev. Biol.

J. Biol. Chem.

Dev. Biol.

Neuron

Brain Res.

Dev. Brain Res.

Trends Neurosci.

Mol. Brain Res.

Dev. Biol.

Dev. Biol.

Survival effect of ciliary neurotrophic factor (CNTF) on chick embryonic motoneurons in culture: comparison with other neurotrophic factors and cytokines

J. Neurosci.

Expression of choline acetyltransferase and nerve growth factor receptor within hypoglossal motoneurons following nerve injury

J. Comp. Neurol.

Research paper
Purification of embryonic rat motoneurons by panning on a monoclonal antibody to the low-affinity NGF receptor