IL-7 acting at many levels of T-Cell production
IL-7 Boosts Immune Response by acting at many levels of Lymphocyte Maturation

Morre and Beq 2012

IL-7 Key Effects to support Immune recovery
Quantity
Production of high counts of new "fresh CD4 and CD8 T Cells
Diversity
By supporting thymopoiesis and improving the sensitivity of the TCR, IL-7 contributes to the broadening of the TCR repertoire
Functionality
By rescuing exhausted PD1, suppressing SOCS-3 and providing new "CD4 helpers" support to "CD8 CTLs", IL-7 produces highly efficient and functional anti-malignant CD8 T Cells
Stability
Boosted by anti-apoptotic effect IL-7 produces long lasting Effectors and Central Memory T Cells > 1yr
Quality
Production of RTE, Naive, Effector, Memory and Central Memory T Cells
Trophicity
Through antagonism of TGFβ and stimulation of CD127+ Lymphoid Tissue inducing cells (LTIs) IL-7 contributes to regeneration of dysfunctional lymphoid tissues (Lymph Nodes, Peyer Patches, Gut mucosa)
The main feature of IL-7 activity to support a long lasting and efficient
immune response: providing T CD4 help to T CD8

Fig adapted from Zander “CD4+ T Cell Help Is Required for the Formation of a Cytolytic CD8+ T Cell Subset that Protects against Chronic Infection and Cancer” Immunity 2020
IL-7 effects contributing to tumor elimination
(Fig adapted from The Cancer Immunity Cycle, Chen Mellman Immunity 2013)
