Novel feedback loop between M2 macrophages/microglia and regulatory B cells in estrogen-protected EAE mice

Area of Science:

• Neuroimmunology
• Endocrinology
• Cellular Biology

Background:

• Sex hormones like estrogen may prevent multiple sclerosis relapses during pregnancy.
• Regulatory B cells are vital for estrogen-mediated protection in experimental autoimmune encephalomyelitis (EAE).

Purpose of the Study:

• To investigate the role of estrogen in inducing regulatory B cells and M2 macrophages/microglia in EAE.
• To elucidate the interaction between M2 macrophages/microglia and regulatory B cells in estrogen-mediated neuroprotection.

Main Methods:

• Treatment of EAE mice with estrogen.
• Analysis of immune cell populations in the spinal cord.
• In vitro co-culture of M2-polarized microglia with B cells.

Main Results:

• Estrogen treatment increased alternatively activated (M2) macrophages/microglia in the spinal cord of EAE mice.
• Estrogen elevated the frequency of regulatory B cells in the spinal cord.
• M2-polarized microglia promoted the induction of regulatory B cells in vitro.

Conclusions:

• Estrogen induces a neuroprotective regulatory feedback loop involving M2 macrophages/microglia and regulatory B cells.
• This interaction is crucial for estrogen-mediated protection against EAE.
• Findings suggest potential therapeutic strategies for multiple sclerosis.