scholarly journals Intra-Species and Inter-Species Differences in Cytokine Production by Porcine Antigen-Presenting Cells Stimulated by Mycoplasma hyopneumoniae, M. hyorhinis, and M. flocculare

Pathogens ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 34 ◽  
Author(s):  
Sarah Fourour ◽  
Corinne Marois-Créhan ◽  
Léa Martelet ◽  
Christelle Fablet ◽  
Isabelle Kempf ◽  
...  
Keyword(s):  
T Cell Activation ◽  
Cell Activation ◽  
Species Differences ◽  
Cytokine Production ◽  
Production Capacity ◽  
Disease Process ◽  
Antigen Presenting Cells ◽  
Tnf Α ◽  
Major Antigen ◽  
Antigen Presenting

Mycoplasma hyorhinis and M. flocculare are commonly co-isolated with M. hyopneumoniae (primary agent of swine enzootic pneumonia) in gross pneumonia-like lesions, but their involvement in the disease process remains unknown. T cells play an immuno-pathological role during mycoplasmal infections. Dendritic cells (DCs) are major antigen-presenting cells involved in T cell activation and differentiation. In this study, we investigated cytokine (IL-6, IL-8, IL-10, IL-12, and TNF-α) production by porcine bone-marrow-derived DCs (BM-DCs) stimulated by M. hyopneumoniae, M. hyorhinis, and/or M. flocculare. Results showed that cytokine production levels were relatively homogenous for all evaluated M. hyopneumoniae strains in contrast to M. hyorhinis and M. flocculare strains. The most noteworthy inter-species differences were the overall (i) lower IL-12 production capacity of M. hyopneumoniae, and (ii) higher TNF-α production capacity of M. flocculare. Co-stimulation of BM-DCs showed that M. hyorhinis dominated the IL-12 production independently of its association with M. hyopneumoniae or M. flocculare. In addition, a decreased BM-DC production of TNF-α was generally observed in the presence of mycoplasma associations. Lastly, M. flocculare association with M. hyopneumoniae increased BM-DC ability to secrete IL-10. A higher cytotoxicity level in BM-DCs stimulated by M. hyorhinis was also observed. Overall, this study demonstrated that the combination of M. hyorhinis or M. flocculare with M. hyopneumoniae may participate to the modulation of the immune response that might affect the final disease outcome.

Abstract MP51: Isolevuglandins In Antigen-presenting Cells, A Biomarker For Salt Sensitivity Of Blood Pressure In Humans?

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Lale Ertuglu ◽  
Fernando Elijovich ◽  
Melis Sahinoz ◽  
Cheryl L Laffer ◽  
Ashley Pitzer ◽  
...  
Keyword(s):  
T Cell Activation ◽  
Cell Activation ◽  
Renal Medulla ◽  
Antigen Presenting Cells ◽  
Dependent Manner ◽  
Salt Loading ◽  
Elevation Changes ◽  
Salt Depletion ◽  
Positive Correlations ◽  
Antigen Presenting

Background: High Na+ stimulates antigen-presenting cells (APCs) in an ENaC dependent manner, with formation of isolevuglandin (isoLG) adducts (neoantigen peptides) that promote T cell activation and salt sensitive (SS) hypertension in rodents. Methods: We studied this pathway in 9 subjects with essential hypertension who discontinued anti-hypertensive therapy for 2 weeks. Their SS was assessed by 24-hrs of salt loading (460 mmoL) and salt depletion (10 mmoL/24 hr, plus furosemide 40 mg x 3). Muscle and skin Na + were measured at baseline (BA) by 23 Na magnetic resonance imaging (NaMRI). The % of APCs containing isoLG adducts (flow cytometry), urine and serum electrolytes and epoxyeicosatrienoic acids (EETs 8-9, 11-12 and 14-15) were measured at BA, after salt-loading (HI) and after salt-depletion (LO). Results: Age was 54 years (48-56), with 23% female, BMI 30 kg/m 2 (28-40) and screening SBP 136 mmHg (120-144), and DBP 85 mmHg (75-99). BA 24-hr urine Na + excretion was 178 (143-212) mmoL, Hi 392 (229-421) and LO 27 (25-29). SBP response to salt-depletion varied from -13.8 to +5.6 mmHg. Muscle Na+ correlated with duration of hypertension (r=0.73, p<0.03) and with SBP, DBP and mean arterial pressure (MAP) during BA, HI and LO (r=0.66 to 0.87). Mean %isoLGs in APCs were not different among the three stages of the protocol but ΔisoLGs due to HI or LO had positive correlations with ΔSBP, ΔDBP and ΔMAP produced by the same interventions (r=0.46 to 0.70). A 10% change in dendritic cell isoLGs predicted a 1.45 mmHg change of SBP in the same direction. Urine (not plasma) EETs (sum of three isoforms) showed negative correlations with isoLGs on the three phases of the protocol (r=0.57 to 0.69), and ΔEETs by HI and LO correlated negatively with ΔisoLGs produced by the same interventions (r=0.58 to 0.77). Conclusions: Muscle Na+ increases with duration of hypertension and correlates with severity of BP elevation. Changes in APC isoLGs due to Na+ loading or depletion seem to be a biomarker of SS of BP in humans. Relations between urine EETs and ΔEETs with APC isoLGs and ΔisoLGs suggest that EETs might be inhibitors of APC ENaC as they are of renal ENaC. Relationships between isoLGs and urine but not plasma EETs suggest that activation of APCs by high salt may occur in the hyperosmolar renal medulla.

scholarly journals Abortive Proliferation of Rare T Cells Induced by Direct or Indirect Antigen Presentation by Rare B Cells In Vivo

1998 ◽  
Vol 187 (10) ◽  
pp. 1611-1621 ◽  
Author(s):  
Sarah E. Townsend ◽  
Christopher C. Goodnow
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Antigen Presentation ◽  
Cell Fate ◽  
T Cell Activation ◽  
Cell Activation ◽  
Antigen Presenting Cells ◽  
Antigen Presenting

Antigen-specific B cells are implicated as antigen-presenting cells in memory and tolerance responses because they capture antigens efficiently and localize to T cell zones after antigen capture. It has not been possible, however, to visualize the effect of specific B cells on specific CD4+ helper T cells under physiological conditions. We demonstrate here that rare T cells are activated in vivo by minute quantities of antigen captured by antigen-specific B cells. Antigen-activated B cells are helped under these conditions, whereas antigen-tolerant B cells are killed. The T cells proliferate and then disappear regardless of whether the B cells are activated or tolerant. We show genetically that T cell activation, proliferation, and disappearance can be mediated either by transfer of antigen from antigen-specific B cells to endogenous antigen-presenting cells or by direct B–T cell interactions. These results identify a novel antigen presentation route, and demonstrate that B cell presentation of antigen has profound effects on T cell fate that could not be predicted from in vitro studies.

scholarly journals Augmentation of T-Cell Activation by Oscillatory Forces and Engineered Antigen-Presenting Cells

Nano Letters ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 6945-6954 ◽  
Author(s):  
Fatemeh S. Majedi ◽  
Mohammad Mahdi Hasani-Sadrabadi ◽  
Timothy J. Thauland ◽  
Song Li ◽  
Louis-S. Bouchard ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Antigen Presenting Cells ◽  
Antigen Presenting
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