Morphological changes in lymph nodes and spleen upon EAE induction in C57BL/6 mic

Abstract

Myelin oligodendrocyte glycoprotein (MOG) is a protein widely used in the induction of experimental autoimmune encephalomyelitis (EAE) for studying human multiple sclerosis (MS). In C57BL/6 female mice aged eight weeks, we administered subcutaneously MOG35-55 peptide in CFA (complete Freund's adjuvant) along with pertussis vaccine injected intraperitoneally. We observed the sign of flaccid tail as early as thirteen days post-immunization in five of twelve animals. Hematoxylin and eosin staining of paraffin-embedded sections of lymph nodes and spleen revealed the presence of germinal centers in the immunized animals. In the control group of animals, lymphoid follicles without germinal centers were observed. Immunohistochemical staining of spleen sections revealed an expression of MHC II molecules in the EAE-induced group. We would like to point out that even though the clinical signs are mild, the morphological changes are apparent in the lymph nodes and spleen of MOG35-55-immunized mice.