Contributions
Abstract: P717
Type: Poster
Abstract Category: Therapy - disease modifying - 27 Neuroprotection and Repair
Background: Leucine-rich repeat and immunoglobulin domain-containing Nogo receptor-interacting protein-1 (LINGO-1) is a negative regulator of oligodendrocyte differentiation, myelination and remyelination. The LINGO family has 4 members: LINGO-1, -2, -3, and -4. LINGO-1, -2 and -3 are specific to the central nervous system. Knock out of LINGO-1, -2, or -3 individually promotes axon regeneration and retinal ganglion cell (RGC) survival in the optic nerve crush model. Previously we demonstrated that anti-LINGO-1 antibody promotes optic nerve regeneration versus antibody-treated controls in an optic nerve crush animal model.
Objectives: To determine if blocking LINGO-1, -2, -3 simultaneously in the optic nerve crush model could result in greater axon regeneration and neuronal protection than targeting LINGO family members individually.
Methods: LINGO-2/3 double knockout and wild type (WT; C57BL6/J) mice were treated with intraperitoneal injections of 6 mg/kg control or anti-LINGO-1 antibodies 1 day before optic nerve crush and weekly thereafter. Optic nerves were crushed ~1 mm behind the optic disk with number 5 forceps for 2 seconds. 2 µg/µl Alexa 647 conjugated cholera toxin β subunit (CTB) was injected intravitreally on day 26 and the mice sacrificed 2 days later, after which optic nerves were dissected and processed. Regenerated axons were quantified by counting the numbers of CTB-labelled axons located 0.5 mm from the crush site. The unpaired t test was used for data analyses.
Results: We observed a 1.3-fold increase in regenerating axons in anti-LINGO-1 antibody-treated LINGO-2/3 double knockout mice compared with anti-LINGO-1 antibody-treated WT mice. At 0.5 mm from the crush site, the estimated mean number of regenerating axons per nerve was 19 (standard error of the mean ±2; n=32) in control antibody-treated WT mice, 28 in anti-LINGO-1 antibody-treated WT mice (±5; n=10), 24 in control antibody-treated LINGO-2/3 double knockout mice (±5; n=4), and 37 in anti-LINGO-1 antibody-treated LINGO-2/3 double knockout mice (±6; n=4).
Conclusions: Optic nerve crush data suggests that blocking LINGO-1/2/3 simultaneously is more efficacious in promoting axon regeneration than blocking LINGO-1 alone. These results support the development of pan-specific anti-LINGO family antibodies to potentially improve axonal regeneration.
Supported by: Biogen.
Disclosure: This study was supported by Biogen (Cambridge, MA, USA). Editorial support was provided by Excel Scientific Solutions (Horsham, UK): funding was provided by Biogen. GS, GH and SM are employees of and hold stock/stock options in Biogen.
Abstract: P717
Type: Poster
Abstract Category: Therapy - disease modifying - 27 Neuroprotection and Repair
Background: Leucine-rich repeat and immunoglobulin domain-containing Nogo receptor-interacting protein-1 (LINGO-1) is a negative regulator of oligodendrocyte differentiation, myelination and remyelination. The LINGO family has 4 members: LINGO-1, -2, -3, and -4. LINGO-1, -2 and -3 are specific to the central nervous system. Knock out of LINGO-1, -2, or -3 individually promotes axon regeneration and retinal ganglion cell (RGC) survival in the optic nerve crush model. Previously we demonstrated that anti-LINGO-1 antibody promotes optic nerve regeneration versus antibody-treated controls in an optic nerve crush animal model.
Objectives: To determine if blocking LINGO-1, -2, -3 simultaneously in the optic nerve crush model could result in greater axon regeneration and neuronal protection than targeting LINGO family members individually.
Methods: LINGO-2/3 double knockout and wild type (WT; C57BL6/J) mice were treated with intraperitoneal injections of 6 mg/kg control or anti-LINGO-1 antibodies 1 day before optic nerve crush and weekly thereafter. Optic nerves were crushed ~1 mm behind the optic disk with number 5 forceps for 2 seconds. 2 µg/µl Alexa 647 conjugated cholera toxin β subunit (CTB) was injected intravitreally on day 26 and the mice sacrificed 2 days later, after which optic nerves were dissected and processed. Regenerated axons were quantified by counting the numbers of CTB-labelled axons located 0.5 mm from the crush site. The unpaired t test was used for data analyses.
Results: We observed a 1.3-fold increase in regenerating axons in anti-LINGO-1 antibody-treated LINGO-2/3 double knockout mice compared with anti-LINGO-1 antibody-treated WT mice. At 0.5 mm from the crush site, the estimated mean number of regenerating axons per nerve was 19 (standard error of the mean ±2; n=32) in control antibody-treated WT mice, 28 in anti-LINGO-1 antibody-treated WT mice (±5; n=10), 24 in control antibody-treated LINGO-2/3 double knockout mice (±5; n=4), and 37 in anti-LINGO-1 antibody-treated LINGO-2/3 double knockout mice (±6; n=4).
Conclusions: Optic nerve crush data suggests that blocking LINGO-1/2/3 simultaneously is more efficacious in promoting axon regeneration than blocking LINGO-1 alone. These results support the development of pan-specific anti-LINGO family antibodies to potentially improve axonal regeneration.
Supported by: Biogen.
Disclosure: This study was supported by Biogen (Cambridge, MA, USA). Editorial support was provided by Excel Scientific Solutions (Horsham, UK): funding was provided by Biogen. GS, GH and SM are employees of and hold stock/stock options in Biogen.