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- Johansson, Maria A., et al.
(författare)
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Probiotic Lactobacilli Modulate Staphylococcus aureus-Induced Activation of Conventional and Unconventional T cells and NK Cells
- 2016
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Lactobacilli are probiotic commensal bacteria and potent modulators of immunity. When present in the gut or supplemented as probiotics, they beneficially modulate ex vivo immune responsiveness. Further, factors derived from several lactobacilli strains act immune regulatory in vitro. In contrast, Staphylococcus aureus (S. aureus) is known to induce excessive T cell activation. In this study, we aimed to investigate S. aureus-induced activation of human mucosal-associated invariant T cells (MAIT cells), gamma delta T cells, NK cells, as well as of conventional CD4(+) and CD8(+) T cells in vitro. Further, we investigated if lactobacilli-derived factors could modulate their activation. PBMC were cultured with S. aureus 161: 2 cell-free supernatants (CFS), staphylococcal enterotoxin A or CD3/CD28-beads alone, or in combination with Lactobacillus rhamnosus GG-CFS or Lactobacillus reuteri DSM 17938-CFS and activation of T and NK cells was evaluated. S. aureus-CFS induced IFN-gamma and CD107a expression as well as proliferation. Costimulation with lactobacilli-CFS dampened lymphocyte-activation in all cell types analyzed. Preincubation with lactobacilli-CFS was enough to reduce subsequent activation, and the absence of APC or APC-derived IL-10 did not prevent lactobacilli-mediated dampening. Finally, lactate selectively dampened activation of unconventional T cells and NK cells. In summary, we show that molecules present in the lactobacilli-CFS are able to directly dampen in vitro activation of conventional and unconventional T cells and of NK cells. This study provides novel insights on the immune-modulatory nature of probiotic lactobacilli and suggests a role for lactobacilli in the modulation of induced T and NK cell activation.
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| 2. |
- van der Heiden, Marieke, et al.
(författare)
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Characterization of the gamma delta T-cell compartment during infancy reveals clear differences between the early neonatal period and 2 years of age
- 2020
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Ingår i: Immunology and Cell Biology. - : Wiley. - 0818-9641 .- 1440-1711. ; 98:1, s. 79-87
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Tidskriftsartikel (refereegranskat)abstract
- gamma delta T cells are unconventional T cells that function on the border of innate and adaptive immunity. They are suggested to play important roles in neonatal and infant immunity, although their phenotype and function are not fully characterized in early childhood. We aimed to investigate gamma delta T cells in relation to age, prematurity and cytomegalovirus (CMV) infection. Therefore, we used flow cytometry to characterize the gamma delta T-cell compartment in cord blood and peripheral blood cells from 14-day-, 2-year- and 5-year-old children, as well as in peripheral blood samples collected at several time points during the first months of life from extremely premature neonates. gamma delta T cells were phenotypically similar at 2 and 5 years of age, whereas cord blood was divergent and showed close proximity to gamma delta T cells from 14-day-old neonates. Interestingly, 2-year-old children and adults showed comparable V delta 2(+) gamma delta T-cell functionality toward both microbial and polyclonal stimulations. Importantly, extreme preterm birth compromised the frequencies of V delta 1(+) cells and affected the functionality of V delta 2(+) gamma delta T cells shortly after birth. In addition, CMV infection was associated with terminal differentiation of the V delta 1(+) compartment at 2 years of age. Our results show an adult-like functionality of the gamma delta T-cell compartment already at 2 years of age. In addition, we demonstrate an altered gamma delta T-cell phenotype early after birth in extremely premature neonates, something which could possible contribute to the enhanced risk for infections in this vulnerable group of children.
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