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Upload organization:Osaka University Graduate School of Medicine  Upload date:2011/06/01

Immune regulation by semaphorins and their receptors

  Professor Atsushi Kumanogo
  Principal Investigator
  Immunopathology Laboratory
  Immunology Frontier Research Center,
  Osaka University

  Address: 2-2 Yamada-oka, Suita, Osaka, Japan

Increasing evidence indicates that the nervous and immune systems have considerable overlap and links. For example, some axon guidance molecules, such as slits and ephrins, have been shown to regulate immune cell migration . In addition, T-cell-Antigen-presenting cell (APC) contact-sites, the so called ‘immunological synapse’, is structurally similar to the ‘neurological synapse’ that connects pairs of neurons. These shared molecules and interactions play critical roles in inducing proper immune responses.
Semaphorins were named for their properties that are analogous to the system of flags and lights that are used in rail and maritime communication. They were initially identified as repulsive axon guidance molecules that were required to direct neuronal axons to their appropriate targets. More than 20 types of semaphorins have been identified, and they have diverse functions in many physiological process, including cardiogenesis, angiogenesis, vasculogenesis, tumor metastasis, osteoclastogenesis, and immune regulation. In the last couple of years, our cumulative findings indicate that several members of semaphorins, so called ‘immune semaphorins’, are crucially involved in various phases of immune responses, that is, these semaphorins regulate immune cell interactions. However, it has been suggested that they are also involved in immune cell trafficking during physiological and pathological immune responses. From a spatio-temporal point of view, however, it is entirely unclear how, where and when immune cells are guided to evoke effective immune responses by semaphoring-signals. In this context, we have a strong desire to conduct research to see the whole picture of immune cell dynamics in more physiological conditions by combinations assays using conventional immunological analysis and imaging methods. Furthermore, beyond such basic implications, the findings from this proposed study may lead to useful insights into manipulation of human immune disorders such as autoimmunity, allergy and immune deficiency.

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