Sirius red stain
In Sirius red–stained tonsillar sections, minimal collagen fibers (stained red) deposition was seen around the follicles in the Control group, while the tonsillar stroma appeared enriched of collagen fibers which organized in thick fascicles in the Placebo group before vitamin D supplementation. The vitamin D-treated group (group III) showed mild collagen fibers deposition in the subepithelial region and around the follicles. (Fig. Photomicrographs of palatine tonsil sections stained with Sirius red stain showing: (