Genetic and epigenetic influence on EAE phenotypes induced with different encephalitogenic peptides

Area of Science:

• Neuroimmunology
• Autoimmune Diseases
• Experimental Models

Background:

• Experimental autoimmune encephalomyelitis (EAE) is a model for multiple sclerosis.
• Different mouse strains and encephalitogenic peptides can elicit distinct EAE phenotypes.
• The influence of peptide specificity on EAE phenotype in genetically identical mice is not fully understood.

Purpose of the Study:

• To investigate whether distinct encephalitogenic peptides induce different EAE phenotypes in genetically identical mice.
• To analyze the impact of myelin proteolipid protein peptides (p139-151 and p215-232) on EAE induction and phenotype.
• To explore the role of epigenetic factors in modulating EAE outcomes.

Main Methods:

• Sensitization of parental SJL, C3H/HeJ, and (SJLXC3H/HeJ)F1 mice with myelin proteolipid protein peptides p139-151 or p215-232.
• Clinical assessment of EAE incidence, severity, and neurological signs.
• Histopathological analysis of central nervous system (CNS) inflammatory and demyelinating lesions.

Main Results:

• Peptide p139-151 induced typical acute EAE in SJL and F1 mice, with spinal cord lesions.
• Peptide p215-232 induced mild disease in C3H/HeJ mice but a spectrum of EAE phenotypes in F1 mice, including acute and later-onset forms with varied lesion distribution.
• F1 mice exhibited EAE phenotypes similar to the susceptible parent for p139-151, but heterogeneous phenotypes for p215-232.

Conclusions:

• The encephalitogenic peptide can determine the EAE phenotype, even in genetically similar mice.
• Specific peptides, like p215-232, can induce a broad range of heterogeneous EAE phenotypes in syngeneic mice.
• Epigenetic factors play a significant role in influencing EAE incidence, onset, severity, and lesion localization.