Ten-Color flow cytometry reveals distinct patterns of expression of CD124 and CD126 by developing thymocytes

<p>Abstract</p> <p>Background</p> <p>We have developed a 12-parameter/10-color flow cytometric staining method for the simultaneous detection and characterization of 21 mouse thymocyte subpopulations that represent discreet stages of T cell development. To demonstrate the utility of this method, we assessed cytokine receptor expression on mouse thymocyte subsets. These experiments revealed distinct patterns of surface expression of receptors for the cytokines IL-4 and IL-6.</p> <p>Results</p> <p>The IL-4 receptor α chain (CD124) was highly expressed on the earliest thymocyte subsets, then downregulated prior to T cell receptor β-selection and finally upregulated in the CD4/CD8 double positive cells prior to positive selection. The IL-6 receptor α chain (CD126) showed a different pattern of expression. It was expressed on the most mature subsets within the CD4 and CD8 single positive (SP) compartments and was absent on all other thymocytes with the exception of a very small cKit^-CD4^-CD8^-population. Intracellular staining of SP thymocytes for phosphorylated STAT-1 demonstrated that IL-6 signaling was confined to the most mature SP subsets.</p> <p>Conclusions</p> <p>This 12-parameter staining methodology uses only commercially available fluorochrome-coupled monoclonal antibodies and therefore could be employed by any investigator with access to a 4-laser flow cytometer. This novel staining scheme allowed us to easily phenotype thymocyte subpopulations that span across development, from the early thymic progenitors (ETPs) to the most mature subsets of the CD4 and CD8 single positive populations.</p

Pilot Associations between Adverse Childhood Experiences, Executive Function, and Brain-Derived Neurotrophic Factor (BDNF) among Adults with Excess Adiposity

Adverse childhood experiences (ACEs) may predict markers of neurocognitive performance (i.e., executive function; EF) and brain health/plasticity (i.e., brain-derived neurotrophic factor; BDNF). This pilot examined: (1) ACES history and current EF performance, (2) ACEs history and current BDNF levels, and (3) current EF performance and BDNF levels. We hypothesized that higher ACEs would be associated with lower EF scores and that these patterns would be associated with serum BDNF levels. Given the pilot nature of the study, emphasis was placed on effect size vs. significance. Participants were 37 middle-aged women. Higher ACEs were not directly associated with EF scores (β = 0.08, p = 0.635) but showed potentially meaningful negative beta coefficients with proBDNF levels (β = −0.22, p = 0.200) and positive coefficients with mature BDNF (β = 0.28, p = 0.094). EF scores and proBDNF showed a positive relationship that did not reach significance (r = 0.28, p = 0.100) similar to EF scores and mature BDNF (r = 0.14, p = 0.406). In a modest pilot sample of middle-aged women with excess weight, higher ACEs were potentially associated with lower proBDNF and higher mature BDNF. Larger follow-up studies are warranted given the size of the detected coefficients and theoretical implications of ACEs and obesity as neurocognitively toxic for brain health and performance

Altered populations of natural killer cells, cytotoxic T lymphocytes, and regulatory T cells in major depressive disorder: Association with sleep disturbance

A subset of individuals with major depressive disorder (MDD) have impaired adaptive immunity characterized by a greater vulnerability to viral infection and a deficient response to vaccination along with a decrease in the number and/or activity of T cells and natural killer cells (NKC). Nevertheless, it remains unclear which specific subsets of lymphocytes are altered in MDD, a shortcoming we address here by utilizing an advanced fluorescence-activated cell sorting (FACS) method that allows for the differentiation of important functionally-distinct lymphocyte sub-populations. Furthermore, despite evidence that sleep disturbance, which is a core symptom of MDD, is itself associated with alterations in lymphocyte distributions, there is a paucity of studies examining the contribution of sleep disturbance on lymphocyte populations in MDD populations. Here, we measured differences in the percentages of 13 different lymphocytes and 6 different leukocytes in 54 unmedicated MDD patients (partially remitted to moderate) and 56 age and sex-matched healthy controls (HC). The relationship between self-reported sleep disturbance and cell counts was evaluated in the MDD group using the Pittsburgh Sleep Quality Index (PSQI). The MDD group showed a significantly increased percentage of CD127low/CCR4+ Treg cells, and memory Treg cells, as well as a reduction in CD56+CD16- (putative immunoregulatory) NKC counts, the latter, prior to correction for body mass index. There also was a trend for higher effector memory CD8+ cell counts in the MDD group versus the HC group. Further, within the MDD group, self-reported sleep disturbance was associated with an increased percentage of effector memory CD8+ cells but with a lower percentage of CD56+CD16- NKC. These results provide important new insights into the immune pathways involved in MDD, and provide novel evidence that MDD and associated sleep disturbance increase effector memory CD8+ and Treg pathways. Targeting sleep disturbance may have implications as a therapeutic strategy to normalize NKC and memory CD8+ cells in MDD