Accurate and precise DNA quantification in the presence of different amplification efficiencies using an improved Cy0 method

Quantitative real-time PCR represents a highly sensitive and powerful technology for the quantification of DNA. Although real-time PCR is well accepted as the gold standard in nucleic acid quantification, there is a largely unexplored area of experimental conditions that limit the application of the Ct method. As an alternative, our research team has recently proposed the Cy0 method, which can compensate for small amplification variations among the samples being compared. However, when there is a marked decrease in amplification efficiency, the Cy0 is impaired, hence determining reaction efficiency is essential to achieve a reliable quantification. The proposed improvement in Cy0 is based on the use of the kinetic parameters calculated in the curve inflection point to compensate for efficiency variations. Three experimental models were used: inhibition of primer extension, non-optimal primer annealing and a very small biological sample. In all these models, the improved Cy0 method increased quantification accuracy up to about 500% without affecting precision. Furthermore, the stability of this procedure was enhanced integrating it with the SOD method. In short, the improved Cy0 method represents a simple yet powerful approach for reliable DNA quantification even in the presence of marked efficiency variations.

Free fatty acid effects on myokine production in combination with exercise mimetics

SCOPE

We aimed to study the effects of free fatty acids (FFAs) alone and combined with the exercise mimetics adrenaline and 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) in the production of IL6, IL15 and Irisin in muscle cells, using a time-sequential model.

METHODS AND RESULTS

Differentiated C2C12 myotubes were treated with FFA, adrenaline or AICAR alone for 0, 1, 3, 8, 12 and 24 h and with double or triple combinations for 0, 3 and 24 h. Levels of mRNA in cells and protein in the medium were measured. Adrenaline, AICAR and FFA showed no significant effects on Irisin expression, while the presence in the culture of adrenaline and/or AICAR decreased IL15 mRNA expression. On contrary, the three signals showed a deep, rapid impact on the IL6 induction, especially when both AICAR and FFA were present.

CONCLUSION

The different response in IL6 versus IL15 regulation may be explained by their different energy-activating versus muscle-cell-hypertrophy suggested roles, considering that adrenaline and AMPK are involved in the activation of energy-generating pathways. Moreover, the results suggest FFAs are components that may regulate IL6 production and may have a role in muscle-adipose tissue crosstalk.

A novel splice variant of folate receptor 4 predominantly expressed in regulatory T cells

BACKGROUND

Regulatory T cells (Tregs) are required for proper maintenance of immunological self-tolerance and immune homeostasis. Folate receptor 4 (FR4) is expressed at high levels in transforming growth factor-beta (TGF-β)-induced Tregs and natural Tregs. Moreover, antibody-mediated targeting of FR4 is sufficient to mediate Treg depletion.

RESULTS

In this study, we describe a novel FR4 transcript variant, FR4D3, in which exon 3 is deleted. The mRNA of FR4D3 encodes a FR4 variant truncated by 189 bp. FR4D3 was found to be predominantly expressed in CD4(+)CD25(+) Treg cells. Overexpression of FR4D3 in CD4(+)CD25(+) Treg cells in vitro stimulated proliferation, which may modulate the ability of these cells to bind and incorporate folic acid.

CONCLUSIONS

Our results suggested that high levels of FR4D3 may be critical to support the substantial proliferative capacity of Treg cells.