Table 1 Signalling alterations occurring with ageing

Intracellular free Ca²⁺

Early T-cell activation

Myo-inositol 1,4,5-trisphosphate production

Calcium release

Protein kinase C isoform translocation

T-cell activation

CD69 expression

Activation surface marker

CD71 expression

Activation surface marker

CD28 expression

Costimulatory molecule

Membrane fluidity

Protein trafficking

Cholesterol content

Lipid rafts movement

Rafts-associated proteins

Early T-cell activation, immune synapse formation

NF-AT distribution

Calcium signalling

Regulation of cellular cholesterol

Molecule sorting, lipid rafts formation

Rafts coalescence

T-cell activation, immune synapse formation

Lck activation

ZAP-70, ITAM phosphorylation

Linker of activated T cells activation

Signalling platform

Fyn activation

ZAP-70, ITAM phosphorylation

ZAP-70 activation

Linker of activated T cells activation

Extracellular signal-regulated kinase activation

Late T-cell activation, proliferation

p38 activation

Late T-cell activation, proliferation

Proteasome activity

NF-κB relocalization