C57BL/6 and Swiss Webster Mice Display Differences in Mobility, Gliosis, Microcavity Formation and Lesion Volume After Severe Spinal Cord Injury

Abstract

Spinal cord injuries (SCI) are neuropathologies causing enormous physical and emotional anguish as well as irreversibly disabilities with great socio/economic burdens to our society. The availability of multiple mouse strains is important for studying the underlying pathophysiological response after SCI. Although strain differences have been shown to directly affect spontaneous functional recovery following incomplete SCI, its influence after complete lesion of the spinal cord is unclear. To study the influence of mouse strain on recovery after severe SCI, we first carried out behavioral analyses up to 6 weeks following complete transection of the spinal cord in mice with two different genetic backgrounds namely, C57BL/6 and Swiss Webster. Using immunohistochemistry, we then analyzed glial cell reactivity not only at different time-points after injury but also at different distances from the lesion epicenter. Behavioral assessments using CatWalk™ and open field analyses revealed increased mobility (measured using average speed) and differential forelimb gross sensory response in Swiss Webster compared to C57BL/6 mice after complete transection of the spinal cord. Comprehensive histological assessment revealed elevated microglia/macrophage reactivity and a moderate increase in astrogliosis in Swiss Webster that was associated with reduced microcavity formation and reduced lesion volume after spinal cord transection compared to C57BL/6 mice. Our results thus suggest that increased mobility correlates with enhanced gliosis and better tissue protection after complete transection of the spinal cord.

CSF1R Inhibition Reduces Microglia Proliferation, Promotes Tissue Preservation and Improves Motor Recovery After Spinal Cord Injury

“…Dynamic walking pattern analysis was done using CatWalk™ (Noldus, Wageningen, Netherlands). We analyzed data with CatMerge (InnovationNet, Tiranges, France), as previously described (Gerber et al, 2012 , 2013 ; Noristani et al, 2018a , b ). Six runs per animal were recorded at each time-point with a minimum inclusion criterion of three runs crossed at the same speed and at least 3-full step sequence patterns per mice per time point.…”

A Matlab-based toolbox for characterizing behavior of rodents engaged in string-pulling

“…The interpretation of this result is that the White mice are displaying an impairment in arm/hand movements relative to Black mice and so use upper arm and body motion for compensation. It is recognized that albino mice display anatomical abnormalities in the visual system ( Lee et al, 2019 ), other physiological processes for example fatty acid uptake and trafficking ( Seeger and Murphy, 2016 ), and recovery after spinal cord injury ( Noristani et al, 2018 ). There is also evidence that albino strains of laboratory animals display motor system abnormalities ( VandenBerg et al, 2002 ; Whishaw et al, 2003 ).…”

Complement C6 deficiency exacerbates pathophysiology after spinal cord injury

“…However, it should be noted that the data presented cannot exclude the possibility of potential variabilities in blood or other immune parameters at baseline between colonies. Additionally, strain differences in SCI lesion pathogenesis are well recognized [61][62][63][64][65][66][67] . It would thus not be surprising that nonlittermate WT and C6-D rats maintained in separate homozygous colonies for generations have diverged, resulting in different functional strain characteristics.…”