Inhibitory proteoglycan immunoreactivity is higher at the caudal than the rostral Schwann cell graft-transected spinal cord interface.
To begin to evaluate the influence that proteoglycans may have on the success of Schwann cell (SC) transplants to induce axonal regrowth across a complete transection lesion and beyond, we determined the pattern of expression of inhibitory chondroitin sulfate proteoglycans (CSPGs) 3 weeks after transplantation into completely transected adult rat thoracic spinal cord. Using immunohistochemistry, we observed that: (1) CSPGs recognized by CS-56 antibody are present on astrocytes, fibroblasts, and SCs in the distal graft, and at lesion and cystic cavity borders; (2) CS-56 immunoreactivity (IR) is greater at the caudal SC graft-host cord interface than the rostral interface; (3) phosphacan-IR, also greater at the caudal interface, is associated with astrocytes, fibroblasts, as yet unidentified cells, and extracellular matrix; (4) neurocan-IR is present on astrocytes and as yet unidentified cells in grey and white matter; and (5) NG2-IR is associated with matrix near SC grafts, unidentified cells mainly in white matter, and lesion borders and cysts. Neither oligodendrocytes nor activated macrophages/microglia were immunostained. In sum, the CSPGs studied are increased at 3 weeks, especially at the caudal SC graft-cord interface, possibly contributing to an inhibitory molecular barrier that precludes regrowing descending axons from entering the caudal host cord.
Plant
G W
GW
The Chambers Family Electron Microscopy Laboratory, The Miami Project to Cure Paralysis, FL, USA. gplant@anhb.uwa.edu.au
Bates
M L
ML
Bunge
M B
MB
D000818:Animals; D000906:Antibodies; D001672:Biocompatible Materials; D011508:Chondroitin Sulfate Proteoglycans / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D003094:Collagen; D004338:Drug Combinations; D005260:Female; D007797:Laminin; D008854:Microscopy, Electron; D009416:Nerve Regeneration / Q000502:physiology; D011509:Proteoglycans; D051381:Rats; D011916:Rats, Inbred F344; D054633:Receptor-Like Protein Tyrosine Phosphatases, Class 5; D012583:Schwann Cells / Q000737:chemistry* / Q000637:transplantation* / Q000648:ultrastructure; D013119:Spinal Cord Injuries / Q000378:metabolism* / Q000473:pathology / Q000601:surgery*
D000906:Antibodies; D001672:Biocompatible Materials; D011508:Chondroitin Sulfate Proteoglycans; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen; C516897:Ptprz1 protein, rat; D054633:Receptor-Like Protein Tyrosine Phosphatases, Class 5