Analytical evaluation of a real-time PCR-based DNA demethylation assay to assess the frequency of naturally occurring regulatory T cells in peripheral blood

ABSTRACT Intrahepatic virus-specific CD8+ T cells are thought to be important for the control of hepatitis C virus (HCV) infection, yet the precise kinetics for the expansion of epitope-specific T cells over the course of infection are difficult to determine with currently available methods. We used a real-time PCR assay to measure the frequency of clonotypic HCV-specific CD8+ T cells in peripheral blood and snap-frozen liver biopsy specimens of two chimpanzees (Pan troglodytes) with previously resolved HCV infection who were rechallenged with HCV. In response to rechallenge, the magnitude of each clonotypic response was 10-fold higher in the liver than in the blood, and the peak clonotype frequency was concurrent with the peak viral load. The higher frequency of HCV-specific clonotypes in the liver than in peripheral blood was maintained for at least 3 months after the clearance of viremia. After antibody-mediated CD8+ T-cell depletion and another viral challenge, the rebound of these clonotypes was seen prior to an appreciable reconstitution of CD8+ T-cell values and, again, at higher frequencies in the liver than in peripheral blood. These data demonstrate the importance of intrahepatic virus-specific CD8+ T cells for the clearance of infection and the rapid kinetics of expansion after virus challenge.

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Real-Time PCR Analysis of Peripheral Blood: A Non-Invasive Technology that can be Used to Assess Tumor Burden in Breast Cancer Patients

10.21236/ada412843 ◽

2002 ◽

Author(s):

Michael Mitas

Keyword(s):

Breast Cancer ◽

Real Time ◽

Cancer Patients ◽

Real Time Pcr ◽

Peripheral Blood ◽

Tumor Burden ◽

Pcr Analysis ◽

Breast Cancer Patients ◽

Non Invasive

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Real-Time PCR Analysis of Peripheral Blood: A Non-Invasive Technology That Can Be Used to Assess Tumor Burden in Breast Cancer Patients

10.21236/ada424096 ◽

2003 ◽

Author(s):

Michael Mitas

Keyword(s):

Breast Cancer ◽

Real Time ◽

Cancer Patients ◽

Real Time Pcr ◽

Peripheral Blood ◽

Tumor Burden ◽

Pcr Analysis ◽

Breast Cancer Patients ◽

Non Invasive

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Regulatory T Cells Fail to Suppress Fast Homeostatic Proliferation In Vitro

Life ◽

10.3390/life11030245 ◽

2021 ◽

Vol 11 (3) ◽

pp. 245

Author(s):

Daniil Shevyrev ◽

Valeriy Tereshchenko ◽

Elena Blinova ◽

Nadezda Knauer ◽

Ekaterina Pashkina ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

T Cells ◽

T Cell ◽

Regulatory T Cells ◽

Autoimmune Diseases ◽

Peripheral Blood ◽

Treg Cells ◽

Homeostatic Proliferation ◽

Suppressive Activity ◽

Healthy Donors

Homeostatic proliferation (HP) is a physiological process that reconstitutes the T cell pool after lymphopenia involving Interleukin-7 and 15 (IL-7 and IL-15), which are the key cytokines regulating the process. However, there is no evidence that these cytokines influence the function of regulatory T cells (Tregs). Since lymphopenia often accompanies autoimmune diseases, we decided to study the functional activity of Tregs stimulated by HP cytokines from patients with rheumatoid arthritis as compared with that of those from healthy donors. Since T cell receptor (TCR) signal strength determines the intensity of HP, we imitated slow HP using IL-7 or IL-15 and fast HP using a combination of IL-7 or IL-15 with anti-CD3 antibodies, cultivating Treg cells with peripheral blood mononuclear cells (PBMCs) at a 1:1 ratio. We used peripheral blood from 14 patients with rheumatoid arthritis and 18 healthy volunteers. We also used anti-CD3 and anti-CD3 + IL-2 stimulation as controls. The suppressive activity of Treg cells was evaluated in each case by the inhibition of the proliferation of CD4+ and CD8+ cells. The phenotype and proliferation of purified CD3+CD4+CD25+CD127lo cells were assessed by flow cytometry. The suppressive activity of the total pool of Tregs did not differ between the rheumatoid arthritis and healthy donors; however, it significantly decreased in conditions close to fast HP when the influence of HP cytokines was accompanied by anti-CD3 stimulation. The Treg proliferation caused by HP cytokines was lower in the rheumatoid arthritis (RA) patients than in the healthy individuals. The revealed decrease in Treg suppressive activity could impact the TCR landscape during lymphopenia and lead to the proliferation of potentially self-reactive T cell clones that are able to receive relatively strong TCR signals. This may be another explanation as to why lymphopenia is associated with the development of autoimmune diseases. The revealed decrease in Treg proliferation under IL-7 and IL-15 exposure can lead to a delay in Treg pool reconstitution in patients with rheumatoid arthritis in the case of lymphopenia.

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Sublingual immunotherapy increases Treg/Th17 ratio in allergic rhinitis

Open Medicine ◽

10.1515/med-2021-0285 ◽

2021 ◽

Vol 16 (1) ◽

pp. 826-832

Author(s):

Jiarong Wang ◽

Liansheng Qiu ◽

Yimin Chen ◽

Minyun Chen

Keyword(s):

T Cells ◽

Allergic Rhinitis ◽

Retrospective Study ◽

Regulatory T Cells ◽

Visual Analog Scale ◽

Peripheral Blood ◽

Sublingual Immunotherapy ◽

Analog Scale ◽

Vas Score ◽

Medication Score

Abstract Background Few studies investigated the effects of sublingual immunotherapy (SLIT) on the peripheral regulatory T cells (Tregs)/Th17 ratio. Objective To investigate the effectiveness of SLIT in children with allergic rhinitis (AR) and the effects on the Tregs/Th17 ratio. Methods This was a retrospective study of children who were treated for AR between April 2017 and March 2018 at one hospital. The patients were grouped according to the treatments they received: SLIT + pharmacotherapy vs pharmacotherapy alone. Results Eighty children (51 boys and 29 girls; 40/group) were included. The visual analog scale (VAS) and medication scores at 1 year in the SLIT + pharmacotherapy group were 2.70 ± 1.08 and 1.1 ± 0.8, respectively, which were lower than at baseline (7.7 ± 1.2 and 3.6 ± 1.0, respectively) (both Ps < 0.05). For the pharmacotherapy group, the VAS score was decreased at 1 year vs baseline (3.3 ± 1.2 vs 7.4 ± 1.0; P < 0.05), but the medication score did not change (P > 0.05). In the SLIT + pharmacotherapy group, the Treg percentage increased, while the Th17 percentage decreased at 1 year (both Ps < 0.01). The percentages of Tregs and Th17s did not change in the pharmacotherapy group (both Ps > 0.05). Conclusions SLIT + pharmacotherapy can increase the Treg percentage and decrease the Th17 percentage in the peripheral blood of children with AR.

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