Gateway reflexes describe novel neuro-immune communications that establish immune cell gateways at specific vessels

Neuroinflammation is an important biological process induced by complex interactions between immune cells and neuronal cells in the central nervous system (CNS). Recent research on the bidirectional communication between neuronal and immunological systems has provided evidence for how immune and inflammatory processes are regulated by nerve activation. One example is the gateway reflex, in which immune cells bypass the blood brain barrier and infiltrate the CNS to cause neuroinflammation. We have found several modes of the gateway reflex in mouse models, in which gateways for immune cells are established at specific blood vessels in the spinal cords and brain in experimental autoimmune encephalomyelitis and systemic lupus erythematosus models, at retinal blood vessels in an experimental autoimmune uveitis model, and the ankle joints in an inflammatory arthritis model. Several environmental stimulations, including physical and psychological stresses, activate neurological pathways that alter immunological responses via the gateway reflex, thus contributing to the development/suppression of autoimmune diseases. In the manuscript, we describe the discovery of the gateway reflex and recent insights on how they regulate disease development. We hypothesize that artificial manipulation of specific neural pathways can establish and/or close the gateways to control the development of autoimmune diseases.

elegans defense against pathogen infection

The innate immune system is a complex collection of physical barriers and physiological defense responses to internal and external environmental assaults. Recent studies in the model organism Caenorhabditis elegans have highlighted how the nervous system interacts with the innate immune system to generate coordinated protective responses. Indeed, studies on neuro-immune interaction pathways have provided mechanistic insights into the roles of neuro-immune communication in modulating both immune and behavioral responses to pathogen attacks. The nervous system releases a variety of neurotransmitters, peptides, and hormones that regulate the innate immune response, while the innate immune system also relays information to the nervous system to affect learning and behavioral responses. Although these interactions still need further investigation, the knowledge that we have gained thus far has improved our understanding of how separate biological systems can act collectively for the survival and well-being of an organism. Here, we review recent studies on neuro-immune communication related to the survival and defense of C. elegans against pathogens.

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Neuro-immune communication is essential for generating coordinated defense against pathogen infection to improve host survival.

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Neuro-immune communication modulates both immune and behavioral responses to pathogen attacks.

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C.elegans is an excellent model system for studying neuro-immune communication.