Feb 19, 2002
BOSTON (Reuters Health)
The chemokine interferon-inducible protein 10 (IP-10) is upregulated in the spinal cord following injury, which recruits T cells into the area and contributes to secondary degeneration, investigators reported at the 168th Annual Meeting of the American Association for the Advancement of Science, held in Boston. Neutralizing IP-10 significantly reduces tissue degeneration and inhibits posttraumatic locomotor deficits.
Dr. Hans S. Keirstead and Rafael Gonzalez, of the University of California at Irvine, along with their colleagues performed dorsal hemisection of the cortical spinal cord in adult mice. While IP-10 was not expressed in the spinal cords of uninjured mice, this T cell chemoattractant was upregulated at 6 hours post-injury, peaking at 12 hours, and returning to baseline levels at 18 hours, Gonzalez told Reuters Health.
Graphic analysis of photographs of the spinal cord in the area of the injury showed a 68% reduction in tissue loss in animals treated with antibodies to IP-10 compared with untreated animals. After staining sections of the spinal cord at day 14, Gonzalez and his associates observed an average of 1365 neurons per square millimeter in uninjured cord, 267 in untreated animals, and 1170 in animals treated with anti-IP-10. That corresponds to a 77% reduction in neuronal loss.
Videography of kinematic parameters--rear paw stride length, hind limb stride width, toe spread, and paw rotation on stepping--showed no change in the untreated, injured animals, while for those treated with anti-IP-10, at approximately 7 days post-injury, parameters had all progressed significantly back toward the uninjured baseline.
"We didn't regenerate neurons, we spared neurons," Gonzalez stressed. "That has clinical applicability, whether somebody ends up in wheelchair, whether they can or cannot control their bladder, or can or cannot move their legs."
"These findings represent a terrific hope for an acute treatment for spinal cord injury and for multiple sclerosis," Dr. Keirstead told Reuters Health. "The ability to stop the secondary degeneration and limit the insult is of tremendous importance because a little bit of tissue sparing translates to a lot of functional recovery. People can walk with 10% of their spinal cord intact."
He added, "We're working as fast
as we can here at the University of California at Irvine to apply this
information in human clinical trials."
© 2002 Reuters Ltd