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  Introduction
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  Intercellular membrane transfer a widespread phenomenon

  • ‐ 
    Intercellular protein transfers between the cells of immune system
  • ‐ 
    Intercellular protein transfer between the cells related – unrelated to immunity
  • ‐ 
    Intercellular protein transfer in the systems unrelated to immunity
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  The pathways responsible for the intercellular membrane transfer [18]

  • ‐ 
    TCR‐mediated internalization and recycling
  • ‐ 
    Dissociation‐associated pathway
  • ‐ 
    Exosome uptake
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    Membrane nanotube formation
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  Functional relevance to immune responses

  • ‐ 
    Stimulatory effect on immune responses
  • ‐ 
    Suppressive effect on immune responses
  • ‐ 
    Unusual phenotypes and negative consequences
  • ‐ 
    Technological consequences
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  Perspectives

In a multicellular system, cellular communication is a must for orchestration and coordination of cellular events. Advent of the latest analytical and imaging tools has allowed us to enhance our understanding of the intercellular communication. An intercellular exchange of proteins or intact membrane patches is a ubiquitous phenomenon, and has been the subject of renewed interest, particularly in the context of immune cells. Recent evidence implicates that intercellular protein transfers, including trogocytosis is an important mechanism of the immune system to modulate immune responses and transferred proteins can also contribute to pathology. It has been demonstrated that intercellular protein transfer can be through the internalization/pathway, dissociation‐associated pathway, uptake of exosomes and membrane nanotube formations. Exchange of membrane molecules/antigens between immune cells has been observed for a long time, but the mechanisms and functional consequences of these transfers remain unclear. In this review, we will discuss the important findings concerning intercellular protein transfers, possible mechanisms and highlight their physiological relevance to the immune system, with special reference to T cells such as the stimulatory or suppressive immune responses derived from T cells with acquired dendritic cell membrane molecules.