The process of covalently altering one or more amino acids in a protein after the protein has been completely translated and released from the ribosome.

The chemical reactions and pathways involving a specific protein, rather than of proteins in general, occurring at the level of an individual cell. Includes cellular protein modification.

Establishment of the glial barrier between the blood and the brain. The glial cells in the brain are packed tightly together preventing the passage of most molecules from the blood into the brain. Only lipid soluble molecules or those that are actively transported can pass through the blood-brain barrier.

Establishment of the glial barrier between the blood and the brain. The glial cells in the brain are packed tightly together preventing the passage of most molecules from the blood into the brain. Only lipid soluble molecules or those that are actively transported can pass through the blood-brain barrier.

A change in the morphology or behavior of a plasmacytoid dendritic cell resulting from exposure to an activating factor such as a cellular or soluble ligand.

A change in the morphology or behavior of a plasmacytoid dendritic cell resulting from exposure to an activating factor such as a cellular or soluble ligand.

A series of molecular signals initiated by activation of a receptor on the surface of a cell. The pathway begins with binding of an extracellular ligand to a cell surface receptor, or for receptors that signal in the absence of a ligand, by ligand-withdrawal or the activity of a constitutively active receptor. The pathway ends with regulation of a downstream cellular process, e.g. transcription.

A series of molecular signals initiated by activation of a receptor on the surface of a cell. The pathway begins with binding of an extracellular ligand to a cell surface receptor, or for receptors that signal in the absence of a ligand, by ligand-withdrawal or the activity of a constitutively active receptor. The pathway ends with regulation of a downstream cellular process, e.g. transcription.

The process in which an antigen-presenting cell expresses a peptide antigen of exogenous origin on its cell surface in association with an MHC class II protein complex. The peptide antigen is typically, but not always, processed from a whole protein.

Any process that stops, prevents, or reduces the frequency, rate or extent of the chemical reactions and pathways resulting in the formation of interleukin-2.

Any process that stops, prevents, or reduces the rate of differentiation of regulatory T cells.

Any process that stops, prevents, or reduces the rate of differentiation of regulatory T cells.

Any process that activates or increases the frequency, rate or extent of natural killer cell mediated cytotoxicity.

Any process that activates or increases the frequency, rate or extent of natural killer cell mediated cytotoxicity.

Any process that modulates the frequency, rate or extent of the immune response, the immunological reaction of an organism to an immunogenic stimulus.

Any process that modulates the frequency, rate or extent of the immune response, the immunological reaction of an organism to an immunogenic stimulus.

Any process that stops, prevents, or reduces the frequency, rate or extent of T cell activation.

The volume enclosed by the membranes of the endoplasmic reticulum.

The external part of the cell wall and/or plasma membrane.

The external part of the cell wall and/or plasma membrane.

A vesicle that is released into the extracellular region by fusion of the limiting endosomal membrane of a multivesicular body with the plasma membrane. Extracellular exosomes, also simply called exosomes, have a diameter of about 40-100 nm.

The space external to the outermost structure of a cell. For cells without external protective or external encapsulating structures this refers to space outside of the plasma membrane. This term covers the host cell environment outside an intracellular parasite.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

The leaflet of the plasma membrane that faces away from the cytoplasm and any proteins embedded or anchored in it or attached to its surface.