Biological and technical variables affecting immunoassay recovery of cytokines from human serum and simulated vaginal fluid: a multicenter study

Polyanionic microbicides modify Toll-like receptor-mediated cervicovaginal immune responses

Topical microbicides are being developed as a preventative approach to reduce the sexual transmission of human immunodeficiency virus type 1 (HIV-1) and other infections. For them to be efficacious, it is believed that they should avoid inducing inflammation while allowing the vaginal epithelium to initiate protective Toll-like receptor (TLR)-mediated innate responses against pathogens. In this study, human cervical and vaginal epithelial cells were exposed to polyanionic HIV entry inhibitors and the following synthetic TLR ligands: (i) the bacterial lipoprotein Pam(3)CSK(4), binding cell surface TLR1/TLR2; (ii) macrophage activating lipopeptide 2 (MALP-2), binding cell surface TLR2/TLR6; and (iii) the viral double-stranded RNA analog poly(I:C), recognized by intracellular TLR3. Cell activation was assessed by nuclear factor kappaB (NF-kappaB) reporter gene transactivation and cytokine production. In spite of enhancing TLR-triggered NF-kappaB activation, the polyanionic microbicide compounds dextran sulfate and polystyrene sulfonate significantly inhibited TLR-mediated cytokine production. They decreased cytokine mRNA and protein levels of proinflammatory (interleukin-8 [IL-8] and IL-1beta) and antiviral (beta interferon) cytokines following epithelial cell stimulation with Pam(3)CSK(4), MALP-2, or poly(I:C). These activities were associated with the sulfate/sulfonate moieties of the polyanionic compounds, since the unsulfated dextran control did not show any effects. Our data demonstrate that these microbicide compounds are capable of selectively interfering with TLR-mediated epithelial responses at different points in their signaling pathways and underscore the importance of expanding the assessment of microbicide compatibility with vaginal innate immune function. Further studies are warranted to determine the impact of this interference on HIV-1 transmission risk.

Socioeconomic position and inflammatory and immune biomarkers of cardiovascular disease: applications to the Panel Study of Income Dynamics

Biomarkers are an important aspect of research linking psychosocial stress and health. This article aims to characterize the biological pathways that may mediate the relationship between socioeconomic position (SEP) and cardiovascular disease (CVD) and address opportunities for further research within the Panel Study of Income Dynamics (PSID), with a focus on psychosocial stressors related to SEP. We review the literature on CVD biomarkers, including adhesion and proinflammatory molecules (interleukin-6, other cytokines, C-reactive proteins, fibrinogen, etc.) and microbial pathogens. The impact of socioeconomic determinants and related psychosocial stressors on CVD biomarkers mediated by behavioral and central nervous system pathways are described. We also address measurement and feasibility issues, including specimen collection methods, processing and storage procedures, laboratory error, and within-person variability. In conclusion, we suggest that PSID consider adding important assessments of specific CVD biomarkers and mediating behavioral measures, health, and medications that will ultimately address many of the gaps in the literature regarding the relationship between SEP and cardiovascular health.