Nano-liquid chromatography-mass spectrometry and recent applications in omics investigations.

Liquid chromatography coupled to mass spectrometry (LC-MS) is one of the most powerful tools in identifying and quantitating molecular species. Decreasing column diameter from the millimeter to micrometer scale is now a well-developed method which allows for sample limited analysis. Specific fabrication of capillary columns is required for proper implementation and optimization when working in the nanoflow regime.

Transcriptomic and Metabolic Responses to a Live-Attenuated Vaccine.

The immune response to live-attenuated vaccine and its host evasion mechanisms are incompletely understood. Using RNA-Seq and LC-MS on samples collected pre-vaccination and at days 1, 2, 7, and 14 post-vaccination, we identified differentially expressed genes in PBMCs, metabolites in serum, enriched pathways, and metabolites that correlated with T cell and B cell responses, or gene expression modules. While an early activation of interferon α/β signaling was observed, several innate immune signaling pathways including TLR, TNF, NF-κB, and NOD-like receptor signaling and key inflammatory cytokines such as Il-1α, Il-1β, and TNF typically activated following infection were suppressed.

Determination of online quenching efficiency for an automated cellular microfluidic metabolomic platform using mass spectrometry based ATP degradation analysis.

As microfluidic cell culture progresses, the need for robust and reproducible intracellular analyses grows. In particular, intracellular metabolites are subject to perturbation and degradation during the lysing process. The reliability of intracellular metabolomic analysis in microfluidic devices depends on the preservation of metabolite integrity during sample preparation and storage.

TLR8-Mediated Metabolic Control of Human Treg Function: A Mechanistic Target for Cancer Immunotherapy.

Regulatory T (Treg) cells induce an immunosuppressive microenvironment that is a major obstacle for successful tumor immunotherapy. Dissecting the regulatory mechanisms between energy metabolism and functionality in Treg cells will provide insight toward developing novel immunotherapies against cancer. Here we report that human naturally occurring and tumor-associated Treg cells exhibit distinct metabolic profiles with selectivity for glucose metabolism compared with effector T cells.

Automated sample preparation in a microfluidic culture device for cellular metabolomics.

Sample pretreatment in conventional cellular metabolomics entails rigorous lysis and extraction steps which increase the duration as well as limit the consistency of these experiments. We report a biomimetic cell culture microfluidic device (MFD) which is coupled with an automated system for rapid, reproducible cell lysis using a combination of electrical and chemical mechanisms. In-channel microelectrodes were created using facile fabrication methods, enabling the application of electric fields up to 1000 V cm(-1).

An evaluation of the natural history of bacterial vaginosis using transition models.

Background: The natural history of bacterial vaginosis (BV) is complex given the variability across and within women over time. This article considers 3 different transition models for analyzing longitudinal BV data.

Methods: Data from the Longitudinal Study of Vaginal Flora were used to evaluate 3 transition modeling strategies: (1) a Markov regression, (2) a Markov regression with random effects, and (3) a mover-stayer model.