Immunohistochemistry of anti-CB2 antibody in spinal cord lesions of dogs with intraspinal spirocercosis.

A) Notice moderate to strong CB2 immunostaining of swollen axons (spheroids) within the white matter. B) Prominent intracytoplasmic staining of large foamy macrophages (gitter cells) with CB2 antibody. C) Severe diffuse infiltration of the subarachnoidal space with strongly CB2 labeled inflammatory cells. D) The CB2 positive leukocyte population mainly consists of macrophages and fewer lymphocytes and plasma cells. IHC was performed using the avidin-biotin-peroxidase complex (ABC) method.