The importance of cellular metabolic adaptation in inducing robust T cell responses is well established. However, the mechanism by which T cells link information regarding nutrient supply to clonal expansion and effector function is still enigmatic. Herein, we report that the metabolic sensor adenosine monophosphate-activated protein kinase (AMPK) is a critical link between cellular energy demand and translational activity and, thus, orchestrates optimal expansion of T cells in vivo. AMPK deficiency did not affect T cell fate decision, activation, or T effector cell generation; however, the magnitude of T cell responses in murine in vivo models of T cell activation was markedly reduced. This impairment was global, as all T helper cell subsets were similarly sensitive to loss of AMPK which resulted in reduced T cell accumulation in peripheral organs and reduced disease severity in pathophysiologically as diverse models as T cell transfer colitis and allergic airway inflammation. T cell receptor repertoire analysis confirmed similar clonotype frequencies in different lymphoid organs, thereby supporting the concept of a quantitative impairment in clonal expansion rather than a skewed qualitative immune response. In line with these findings, in-depth metabolic analysis revealed a decrease in T cell oxidative metabolism, and gene set enrichment analysis indicated a major reduction in ribosomal biogenesis and mRNA translation in AMPK-deficient T cells. We, thus, provide evidence that through its interference with these delicate processes, AMPK orchestrates the quantitative, but not the qualitative, manifestation of primary T cell responses in vivo.
- MeSH
- adenylátkinasa genetika metabolismus MeSH
- aktivace lymfocytů MeSH
- buňky Th17 fyziologie MeSH
- CD4-pozitivní T-lymfocyty MeSH
- DNA vazebné proteiny genetika metabolismus MeSH
- fyziologická adaptace MeSH
- kolitida imunologie MeSH
- messenger RNA genetika metabolismus MeSH
- myši knockoutované MeSH
- myši MeSH
- převzatá imunita MeSH
- regulace genové exprese enzymů MeSH
- regulační T-lymfocyty fyziologie MeSH
- T-lymfocyty pomocné-indukující fyziologie MeSH
- Th1 buňky fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Acyclic nucleotide analogue PMEG represents promising drug candidate against lymphomas. In the present work we describe the ability of PMEG to induce resistance and we elucidate the mechanisms involved in this process. CCRF-CEM T-lymphoblastic cells resistant to either PMEG or its 6-amino congener PMEDAP were prepared and assayed for the expression of membrane transporters, PMEG and PMEDAP uptake and intracellular metabolism. Genes for guanylate kinase (GUK) and adenylate kinase (AK) isolated from PMEG- and PMEDAP-resistant cells were sequenced and cloned into mammalian expression vectors. PMEG-resistant cells were transfected with GUK vectors and catalytic activities of GUKs isolated from PMEG-sensitive and resistant cells were compared. PMEG phosphorylation to PMEG mono- and diphosphate was completely impaired in resistant cells. GUK obtained from PMEG-resistant cells revealed two point mutations S(35)N V(168)F that significantly suppressed its catalytic activity. Transfection of resistant cells with wtGUK led to the recovery of phosphorylating activity as well as sensitivity towards PMEG cytotoxicity. No differences in PMEG uptake have been found between sensitive and resistant cells. In contrast to GUK no changes in primary sequence of AK isolated from PMEDAP resistant cells were identified. Therefore, resistance induced by PMEDAP appears to be conferred by other mechanisms. In conclusion, we have identified GUK as the sole molecular target for the development of acquired resistance to the cytotoxic nucleotide PMEG. Therefore, PMEG is unlikely to cause cross-resistance in combination therapeutic protocols with most other commonly used anticancer drugs.
- MeSH
- adenin analogy a deriváty farmakokinetika farmakologie MeSH
- adenylátkinasa genetika MeSH
- bodová mutace MeSH
- chemorezistence MeSH
- fosforylace MeSH
- guanin analogy a deriváty farmakokinetika farmakologie MeSH
- guanylátkinasy genetika MeSH
- kultivované buňky MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- organofosforové sloučeniny farmakokinetika farmakologie MeSH
- protinádorové látky farmakologie MeSH
- sekvence aminokyselin MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Data are presented on the red cell acid phosphatase (ACP), phosphoglucomutase (PGM1), and adenylate kinase (AK) iso-enzyme distributions in a sample of gypsies (Roms) from Slovakia (Czechoslovakia). The findings of very low Pa (0.289) and PGM11 (0.656) gene frequencies as well as the complete absence of the Pc gene are in accordance with the generally accepted assumption of the Indian origin of European gypsies, and demonstrate that the rate of European admixture in Slovak gypsies is low. The finding of a very high AK1 gene frequency (0.984), on the other hand, contradicts this assumption, but with the limited available data on the iso-enzyme distribution in other gypsy and in Indian populations it cannot readily be explained.
- MeSH
- adenylátkinasa krev genetika MeSH
- erytrocyty enzymologie MeSH
- etnicita * MeSH
- fosfoglukomutasa krev genetika MeSH
- frekvence genu MeSH
- izoenzymy genetika MeSH
- kyselá fosfatasa krev genetika MeSH
- lidé MeSH
- polymorfismus genetický MeSH
- Romové * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Geografické názvy
- Československo MeSH
