Chronic pain often accompanies immune-related diseases with an elevated level of IgG immune complex （IgG-IC） in the serum and/or the affected tissues though the underlying mechanisms are largely unknown. Fc gamma re...Chronic pain often accompanies immune-related diseases with an elevated level of IgG immune complex （IgG-IC） in the serum and/or the affected tissues though the underlying mechanisms are largely unknown. Fc gamma receptors （FcyRs）, known as the receptors for the Fc domain of immunoglobulin G （IgG）, are typically expressed on immune cells. A general consensus is that the activation of FcyRs by IgG-IC in such immune cells induces the release of proinflammatory cytokines from the immune cells, which may contribute to the IgG-IC-mediated peripheral sensitization. In addition to the immune cells, recent studies have revealed that FcyRI, but not FcyRII and FcyRIII, is also expressed in a subpopulation of primary sensory neurons. Moreover, IgG-IC directly excites the primary sensory neurons through neuronal FcyRI. These findings indicate that neuronal FcyRI provides a novel direct linkage between immunoglobulin and primary sensory neurons, which may be a novel target for the treatment of pain in the immune-related disorders. In this review, we summarize the expression pattern, functions, and the associated cellular signaling of FcyRs in the primary sensory neurons.展开更多
基金supported by a fellowship(2012-2014)from the Canadian Institutes of Health Research(CIHR)
文摘Chronic pain often accompanies immune-related diseases with an elevated level of IgG immune complex （IgG-IC） in the serum and/or the affected tissues though the underlying mechanisms are largely unknown. Fc gamma receptors （FcyRs）, known as the receptors for the Fc domain of immunoglobulin G （IgG）, are typically expressed on immune cells. A general consensus is that the activation of FcyRs by IgG-IC in such immune cells induces the release of proinflammatory cytokines from the immune cells, which may contribute to the IgG-IC-mediated peripheral sensitization. In addition to the immune cells, recent studies have revealed that FcyRI, but not FcyRII and FcyRIII, is also expressed in a subpopulation of primary sensory neurons. Moreover, IgG-IC directly excites the primary sensory neurons through neuronal FcyRI. These findings indicate that neuronal FcyRI provides a novel direct linkage between immunoglobulin and primary sensory neurons, which may be a novel target for the treatment of pain in the immune-related disorders. In this review, we summarize the expression pattern, functions, and the associated cellular signaling of FcyRs in the primary sensory neurons.
