H2020Индивидуална стипендия2019–2021

skILL · Intracellular signalling by modified lipopolysaccharide

„Хоризонт 2020“ — Действия „Мария Склодовска-Кюри“

Период: 2019-04-25 → 2021-04-24
Финансиране от ЕС: 177 599 €
Участници: 1
Схема: MSCA-IF-EF-SE

Линиите свързват координатора с партньорите.

Накратко на български

Промените в структурата на липополизахаридите от бактерията Neisseria meningitidis влияят на това как клетките активират вътрешния си имунен отговор чрез специфичен протеинов път. Тези данни помагат за разработването на по-безопасни ваксини и компоненти за стимулиране на имунитета.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

Intracellular signalling by modified lipopolysaccharide

Neisseria meningitidis typically produces a very potent hexa-acylated lipopolysaccharide (LPS) which is too toxic for therapeutic applications. An important determinant of this endotoxic activity is recognition of the membrane-anchoring lipid A moiety of LPS by the TLR4/MD-2 receptor. We have previously developed an extensive set of meningococcal lipid A mutants which cover the whole range of TLR4 activation, from wildtype level to practically zero. However, determining only their TLR4 recognition properties will give an incomplete picture of biological activity, as recent studies have identified the non-canonical inflammasome pathway as an additional recognition system for LPS. However, there is very limited information on how structural alterations in LPS mutants affect activation of this newly identified intracellular caspase pathway. A major aim of the project has been to obtain this information. In vitro assays have been applied with cell lines into which LPS is introduced intracellularly. Methods have been introduced and used to specifically measure the non-canonical caspase pathway, in both mouse and human cells and with a large panel of LPS variants. Overall, the obtained results demonstrate that the mutant meningococcal LPSs mediate graded non-canonical inflammasome activation, with maximal activity for wildtype LPS and reduced or absent activity for penta- or tetra-acylated LPS species. In comparison to the TLR4/MD-2 complex signalling pathway much less is known about the detailed structure-function relationships of modified LPS structures and their degree of caspase activation. Our results are among the first to provide this information, which is important for the practical application of LPS variants as adjuvants, vaccine components and immunomodulators.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

The adjuvant potential of bacterial lipopolysaccharide (LPS) for vaccines depends on a detailed understanding of its innate immune signalling properties, in order to achieve the right balance between immunogenicity and reactogenicity. By biosynthetic engineering of meningococcal LPS, we have obtained a unique panel of mutants covering a wide range of endotoxic activity, from the maximum wildtype level to almost totally inactive. However, this is based on activation of the TLR4/MD-2 receptor, and recent studies have revealed that LPS endotoxic activity is also mediated by the intracellular receptor caspase 4 (caspase 11 in the mouse). At present, it is not clear how this contributes to the overall biological activity of LPS, and how it can be modified by structural alterations to the lipid A moiety of LPS. A major contribution of the proposed project will be to provide for the first time a detailed structure-function relationship for this LPS-caspase 4/11 interaction. This information will be crucial in the further evaluation of the adjuvant potential of these LPS derivatives, as well as giving more insight in the role of LPS modification in the interaction of pathogenic bacteria with the innate immune system. LPS mutants with differential effects on the TLR4 and caspase pathways will provide a unique opportunity to tease apart the contributions of both pathways to the overall LPS biological activity. In addition, we will explore the role of delivery of LPS by OMVs (outer membrane vesicles) to the intracellular pathway activation. A second and complementary contribution will be the development of novel LPS purification methods, which will also lead to better understanding of LPS structure-function relationships by allowing the separation of complicated LPS mixtures in their individual molecular species. In addition, they will pave the way for purification procedures which can be upscaled for making clinical grade LPS in human vaccine applications.

Оригинален текст от CORDIS (на английски).

Участници

MINISTERIE VAN VOLKSGEZONDHEID, WELZIJN EN SPORT · Den HaagКоординаторНидерландия