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Biology subjects

Kadekar, D.

Publications and source records attributed to Kadekar, D..

3 recordsLinked to original sources

The retinoic acid receptor drives neuroinflammation and fine tunes the homeostasis of interleukin-17-producing T cells

The vitamin A metabolite retinoic acid (RA) is critical for the maturation and function of the immune system, however, our knowledge regarding its role in gamma delta ({gamma}{delta}) T cells is limited. By specifically inactivating the RA receptor alpha (RAR) in type 3 lymphocytes and using a combination of fetal thymic organ cultures and single-cell RNA-sequencing we found that RA strengthened TCR signaling to limit the embryonic development of interleukin(IL)-17-producing {gamma}{delta} T cells ({gamma}{delta}T17), while at the same time it promoted their survival after birth. In adult mice, RA imposed a multi-level transcriptional program allowing {gamma}{delta}T17 cells to become activated, survive and sense interferon. Consequently, cells with inactive RAR responded poorly to immunization and produced low level of cytokines leading to near disease resistance in the experimental autoimmune encephalomyelitis model. Finally, RA was required for optimal expression of the 4{beta}1 integrin and {gamma}{delta}T17 cell infiltration to the brain. Collectively, these studies suggest that by acting at various stages during the lifetime of {gamma}{delta} T cells, RA supports their normal development, their survival and their ability to respond to inflammatory stimuli.

immunology↗

Inhibitor of apoptosis proteins 1 and 2 are required for the homeostasis of murine RORγt+ γδ T cells

Environmental and molecular cues early in life are often associated with the permanent shaping of our immune system during adulthood. Although increasing, our knowledge of the signaling pathways that operate in early life and their temporal mode of action is limited. Herein, we demonstrate that the cellular inhibitor of apoptosis proteins 1 and 2 (cIAP1/2), which are E3 ubiquitin ligases and master regulators of the nuclear factor-kappa B (NF-{kappa}B) pathway, function during late neonatal and prepubescent life to sustain interleukin(IL)-17-producing gamma delta T cells ({gamma}{delta}T17) and group 3 innate lymphoid cells (ILC3). We show that cell-intrinsic deficiency in cIAP1/2 at 3-4 weeks of life leads to downregulation of the transcription factors cMAF and ROR{gamma}t, and failure to enter cytokine-induced cell cycle. This is followed by progressive loss of {gamma}{delta}T17 cells and ILC3 while mice are aging. Mice deficient in cIAP1/2 have severely reduced {gamma}{delta}T17 cells and ILC3, present with suboptimal {gamma}{delta}T17 responses in the skin, lack small intestinal isolated lymphoid follicles and cannot control intestinal bacterial infection. Mechanistically, these effects appear to be dependent on overt activation of the non-canonical NF-{kappa}B pathway. Our data identify the cIAP E3 ubiquitin ligases as critical early life molecular switches for establishing effective type-3 immunity during aging.

immunology↗

The neonatal microenvironment programs conventional and intestinal Tbet+ γδT17 cells through the transcription factor STAT5

Interleukin(IL)-17-producing ROR{gamma}t+ {gamma}{delta} T ({gamma}{delta}T17) cells develop in the embryonic thymus and participate in type 3 immune responses. Herein we show that {gamma}{delta}T17 cells rapidly proliferate within neonatal lymph nodes and gut, where upon entry they uniquely upregulate Tbet and co-express IL-17, IL-22 and interferon(IFN) {gamma} in a STAT3 and retinoic acid dependent manner. Neonatal expansion was halted in mice conditionally deficient in STAT5 and its loss resulted in {gamma}{delta}T17 cell depletion from all adult organs. Hyperactive STAT5 mutant mice showed that the STAT5A homologue had a dominant role over STAT5B in promoting {gamma}{delta}T17 cell expansion and downregulating gut-associated Tbet. In contrast, STAT5B preferentially expanded IFN{gamma}-producing {gamma}{delta} populations. Importantly, mice lacking {gamma}{delta}T17 cells due to STAT5 deficiency displayed a profound resistance to experimental autoimmune encephalomyelitis. Our data identify for the first time STAT5 as a key molecular checkpoint allowing {gamma}{delta}T17 cells to pass through a critical neonatal developmental window to acquire tissue-specific characteristics essential for infection and autoimmunity.

immunology↗