Immunomodulatory oligonucleotide IMT504: Effects on mesenchymal stem cells as a first-in-class immunoprotective/immunoregenerative therapy

Figure 3 Effect of the IMT504 treatment on bone structure in ovariectomized (osteoporotic) rats. Female Sprague-Dawley 16-wk-old rats underwent ovariectomy (OVX). When animals were 1-year-old, half of them (treated group) received a subcutaneous dose of IMT504 (20 mg/kg per dose in saline) injected daily for 5 successive days. The other half-received saline under the same scheme (non-treated group). The treatment was repeated 30 d later. A group of non-OVX rats served as control. Body weight and general health was measured weekly. One month after the last treatment, animals were euthanized and femurs dissected, decalcified and embedded in paraffin. Slides of 0.5-μm sections of the distal femur were generated using a Leica RM2145 microtome, stained with hematoxylin and eosin, and examined by light microscopy. Digital images were recorded with a Nikon Coolpix 4500 camera at 16.5-fold magnification under a Leica MZ16A stereomicroscope. Three fields in each slide were evaluated, totaling a combined area of 3 mm². Trabecular bone was identified, and its perimeter and area measured. Histomorphometric analysis was performed using the Image Pro-Plus 4.5 software and standard histomorphometric parameters calculated (our unpublished results).