aFGF Promotes Axonal Growth in Rat Spinal Cord Organotypic Slice Co-Cultures

Abstract

This study developed a slice culture model system to study axonal regeneration after spinal cord injury. This model was tested in studies of the roles of acidic fibroblast growth factor (aFGF) and peripheral nerve segments in axonal growth between pieces of spinal cord. Transverse sections of P15-P18 Sprague-Dawley rat spinal cord were collected for organotypic slice cultures. Group I consisted of two slices of spinal cord in contact with each other during the culture period. Group II consisted of two slices that were separated by 3 mm and connected by two segments of intercostal nerves. Group III consisted of single slices for studies of neuron survival. Some cultures from each group included aFGF in the culture medium. Bromodeoxyuridine (BrdU) was included in the medium for some cultures. The results showed three principal findings. First, counts of neurofilament-positive cells demonstrated that treatment with aFGF significantly increased the number of surviving neurons in culture. Second, neurofilament immunostaining and DiI tracing demonstrated axons crossing the junction between the two pieces of spinal cord or growing through the intercostal nerve segments, and these axons were seen only in cultures with aFGF treatment. Third, few cells were double stained for neurofilament and BrdU, and these were found only with aFGF treatment. These results demonstrate that (1) organotypic slice cultures present a useful model to study regeneration from spinal cord injury, (2) aFGF rescues neurons and promotes axonal growth in these cultures, and (3) segments of intercostal nerves promote axon growth between slices of spinal cord.

Freeze-dried poly(d,l-lactic acid) macroporous guidance scaffolds impregnated with brain-derived neurotrophic factor in the transected adult rat thoracic spinal cord

“…The glue contained 1% fibrinogen (Type 1 from human plasma; Sigma), 2% CaCl 2 , 2% gentamicin (Gemini Bioproducts, Inc., Calabasas, CA) 2% aprotinin (Sigma), and FGF1 (2 µg/ml; Sigma). FGF1 was added to limit additional spinal tissue loss [43,44] and to serve as a soft intermediate between the cord stumps and the implant. The injury area was rinsed with sterile saline supplemented with 0.1% gentamicin (Sigma).…”

An in vitro spinal cord injury model to screen neuroregenerative materials

“…They provide a versatile bridge between isolated cell culture and in vivo experiments wherein the cytoarchitecture and structural relationships of cells are maintained, allowing for parameters 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 of neural regeneration, e.g. neuronal survival [19], nerve fiber regeneration [20,21] and collateral axon sprouting to be evaluated [22]. These models offer several advantages including the ease of manipulation/observation of in vitro preparations [18]; several ages, neuroanatomical areas and species, including human foetuses [23] and transgenic models [24,25] can be used as tissue donor sources, offering high flexibility to study neural pathologies and disease mechanisms.…”

Functional recovery of chronic complete idiopathic transverse myelitis after administration of neurotrophic factors

“…Recent studies revealed that aFGF facilitates nerve regeneration and increases the efficacy of sprouting in rats with spinal cord and cervical root transection. [17][18][19] Our patient responded well to intrathecal application of aFGF. She had no side effects, and the results of the treatment could be maintained under a regular rehabilitation program.…”