Publications

BACKGROUND

The ontogenesis of the epidermal permeability barrier is complex and incompletely understood. Previously we showed that IL-1 and TNFalpha regulate permeability barrier homeostasis in adult mice.

OBJECT

We determined whether IL-1 and TNFalpha also regulate fetal barrier development.

METHODS

Messenger RNA and protein levels in epidermis were determined by real-time PCR and immunohistochemistry, respectively. Epidermal ultra-structure was examined by electron microscopy.

RESULTS

The protein expression of IL-1alpha/beta and TNFalpha peaked in fetal rat epidermis at gestational age d19-20, a time point that coincides with the formation of a competent barrier. Treatment of fetal rat explants with IL-1 or TNFalpha accelerates barrier formation in a time- and dose-related fashion, evidenced by a decrease in transepidermal water loss attributable to the presence of mature morphology and an increase in the expression of cornified envelope proteins. Using single receptor KO mice, we demonstrated a delay in both barrier formation and cornified envelope protein expression, paralleled with immature lamellar membranes in epidermis of IL-1R KO, but not TNFR KO vs. wild-type at day 17, differences that disappeared in later gestational stages and immediately after birth. Using TNF receptor and IL-1 receptor double knock out (D-KO) mice, we further demonstrated that a transient delay in barrier development consistently occurs in epidermis of D-KO mice.

CONCLUSION

IL-1 plays a role in regulating the late stages of SC formation and permeability barrier ontogenesis.

BACKGROUND

How hepatitis C virus (HCV) affects coronary heart disease (CHD) risk factors and outcomes is largely unknown.

METHODS AND RESULTS

Among a cohort of patients with stable CHD, we examined the association between HCV seropositivity and levels of inflammatory markers (C-reactive protein [CRP], fibrinogen, interleukin-6, and tumor necrosis factor [TNF]-alpha) and risk for the following outcomes: death, cardiovascular (CV) events, and heart failure events. A total of 84 (8.6%) participants were found to be seropositive for HCV. HCV-seropositive patients were found to have significantly lower adjusted mean levels of CRP (2.6 vs. 4.4; P < .01) and fibrinogen (340 vs. 398; P < .01), but higher levels of TNF-alpha (7.1 vs. 4.8; P < .01). Age-adjusted rates for HCV seropositive vs. seronegative were as follows: death 93 vs. 42/1,000p-y (P < .01), CV events 62 vs. 40 (P=.13), and heart failure 76 vs. 29 (P < .01). After adjustment for demographic and clinical factors, HCV remained significantly associated with an increased risk for heart failure events (HR=2.13; 95% CI: 1.19-3.80).

CONCLUSIONS

In this cohort with CHD, HCV seropositive participants had higher rates of death, CV events, and heart failure hospitalizations during follow-up. After adjustment for CV risk factors, HCV seropositivity remained independently associated with risk for heart failure events.

BACKGROUND

The Raloxifene Use for The Heart (RUTH) trial showed that raloxifene, a selective estrogen receptor modulator, had no overall effect on the incidence of coronary events in women with established coronary heart disease or coronary heart disease risk factors. We provide detailed results of the effect of raloxifene on coronary outcomes over time and for 24 subgroups (17 predefined, 7 post hoc).

METHODS AND RESULTS

Postmenopausal women (n=10 101; mean age, 67 years) were randomized to raloxifene 60 mg/d or placebo for a median of 5.6 years. Coronary outcomes were assessed by treatment group in women with coronary heart disease risk factors and those with established coronary heart disease. Raloxifene had no effect on the incidence of coronary events in any subgroup except in the case of a post hoc age subgroup analysis using age categories defined in the Women's Health Initiative randomized trials. The effect of raloxifene on the incidence of coronary events differed significantly by age (interaction P=0.0118). The incidence of coronary events in women <60 years of age was significantly lower in those assigned raloxifene (50 events) compared with placebo (84 events; hazard ratio, 0.59; 95% confidence interval, 0.41 to 0.83; P=0.003; absolute risk reduction, 36 per 1000 women treated for 1 year). No difference was found between treatment groups in the incidence of coronary events in women > or =60 and <70 or > or =70 years of age.

CONCLUSIONS

In postmenopausal women at increased risk of coronary events, the overall lack of benefit of raloxifene was similar across the prespecified subgroups.

BACKGROUND

Vascular calcification is highly prevalent in persons with chronic kidney disease (CKD) and predicts cardiovascular disease (CVD) events. Matrix Gla protein (MGP) is a potent inhibitor of vascular calcification, and lower levels of its precursor-uncarboxylated MGP (ucMGP)--are associated with vascular calcification and atherosclerosis. Whether mild to moderate decrements in kidney function are associated with lower serum ucMGP is unknown.

METHODS

In a cross-sectional study among 842 outpatients with stable CVD, estimated glomerular filtration rate (eGFR), serum cystatin-C and urine albumin-to-creatinine ratio (ACR) were measured and serum ucMGP levels were determined by ELISA. Multivariate linear regression evaluated the association of each kidney function measure with serum ucMGP levels.

RESULTS

The mean eGFR was 76 +/- 23 mL/min/1.73 m(2), and 186 subjects (22%) had moderate CKD (eGFR <60 mL/min/1.73 m(2)). The mean +/- SD ucMGP level was 3289 +/- 1177 nM. In unadjusted analysis, each 10 mL/ min/1.73 m(2) lower eGFR was associated with 101 nM lower ucMGP level. This association was only minimally attenuated in final multivariate models wherein each 10 mL/ min/1.73 m(2) lower eGFR was associated with 79 nM lower ucMGP (95% confidence interval [CI]; 44 to 115; P < 0.001) after adjustment for age, sex, race, body mass index, blood pressure, smoking, hypertension, diabetes; and serum albumin, calcium, phosphorus, and fetuin-A levels. Similarly, in models adjusted for identical covariates, each 0.1 mg/L higher cystatin-C was associated with 39 nM lower ucMGP (95% CI 23 to 55; P < 0.001). In contrast, no significant association was observed between ACR and ucMGP in either unadjusted or adjusted analyses (adjusted P = 0.17). All associations were similar among subjects with or without diabetes (P-values for interaction > 0.50).

CONCLUSIONS

Among outpatients with stable CVD, a reduced glomerular filtration rate is associated with a decreased serum ucMGP level. In contrast, ACR is not associated with ucMGP levels. Whether ucMGP is a useful marker of vascular calcification and CVD event risk in persons with CKD deserves future study.

BACKGROUND

The relationship of elevated T cell activation to altered T cell differentiation profiles, each defining features of HIV-1 infection, has not been extensively explored. We hypothesized that anti-retroviral suppression of T cell activation levels would lead to alterations in the T cell differentiation of total and HIV-1 specific CD8+ T cell responses among recently HIV-1 infected adults.

METHODOLOGY/PRINCIPAL FINDINGS

We performed a longitudinal study simultaneously measuring T cell activation and maturation markers on both total and antigen-specific T cells in recently infected adults: prior to treatment; after the initiation of HAART; and after treatment was halted. Prior to treatment, HIV-1 Gag-specific CD8+ T cells were predominantly of a highly activated, intermediate memory (CD27+CD28-) phenotype, while CMV pp65-specific CD8+ T cells showed a late memory (CD27-CD28-), low activation phenotype. Participants with the highest fraction of late memory (CD27-CD28-) HIV-1-specific CD8+ T cells had higher CD4+ T cell counts (rho = +0.74, p = 0.004). In turn, those with the highest fraction of intermediate memory (CD27+ CD28-) HIV-1 specific CD8+ T cells had high total CD8+ T cell activation (rho = +0.68, p = 0.01), indicating poorer long-term clinical outcomes. The HIV-1 specific T cell differentiation profile was not readily altered by suppression of T cell activation following HAART treatment.

CONCLUSIONS/SIGNIFICANCE

A more differentiated, less activated HIV-1 specific CD8+ T cell response may be clinically protective. Anti-retroviral treatment initiated two to four months after infection lowered T cell activation but had no effect on the differentiation profile of the HIV-1-specific response. Intervention during the first month of acute infection may be required to shift the differentiation phenotype of HIV-1 specific responses to a more clinically favorable profile.