Th17 Cytokines Stimulate CCL20 Expression in Keratinocytes In Vitro and In Vivo: Implications for Psoriasis Pathogenesis

T helper (Th) 17 cells have recently been implicated in psoriasis pathogenesis, but mechanisms of how these cells traffic into inflamed skin are unknown. By immunostaining for interleukin (IL)-17A and IL-22, we show numerous cells present in psoriasis lesions that produce these cytokines. We next found that Th17 cytokines (IL-17A, IL-22, and tumor necrosis factor (TNF)-α) markedly increased the expression of CC chemokine ligand (CCL) 20, a CC chemokine receptor (CCR)6 ligand, in human keratinocyte monolayer and raft cultures in a dose- and time-dependent manner. Lastly, we showed in mice that subcutaneous injection with recombinant IL-17A, IL-22, or TNF-α led to the upregulation of both CCL20 and CCR6 expression in skin as well as cutaneous T-cell infiltration. Taken together, these data show that Th17 cytokines stimulate CCL20 production in vitro and in vivo, and thus provide a potential explanation of how CCR6-positive Th17 cells maintain their continual presence in psoriasis through a positive chemotactic feedback loop

Characteristics of mycoplasma genitalium urogenital infections in a diverse patient sample from the United States: Results from the aptima mycoplasma genitalium evaluation study (AMES)

Data from a large prospective multicenter clinical validation study of a nucleic acid amplification in vitro diagnostic test for Mycoplasma genitalium were analyzed to describe the prevalence of M. genitalium infection, risk factors, and disease associations in female and male patients seeking care in diverse geographic regions of the United States. Among 1,737 female and 1,563 male participants, the overall prevalence of M. genitalium infection was 10.3% and was significantly higher in persons ages 15 to 24 years than in persons ages 35 to 39 years (for females, 19.8% versus 4.7% [odds ratio {OR} = 5.05; 95% confidence interval {CI} = 3.01 to 8.46]; for males, 16.5% versus 9.4% [OR = 1.91; 95% CI = 1.20 to 3.02]). The risk for M. genitalium infection was higher in black than in white participants (for females, 12.0% versus 6.8% [OR = 1.88; 95% CI = 1.30 to 2.72]; for males, 12.9% versus 6.9% [OR = 2.02; 95% CI = 1.38 to 2.96]) and higher in non-Hispanic than in Hispanic participants (for females, 11.2% versus 6.0% [OR = 1.97; 95% CI = 1.25 to 3.10]; for males, 11.6% versus 6.8% [OR = 1.80; 95% CI = 1.14 to 2.85]). Participants reporting urogenital symptoms had a significantly elevated risk of M. genitalium infection compared to that for asymptomatic individuals (for females, OR = 1.53 [95% CI = 1.09 to 2.14]; for males, OR = 1.42 [95% CI = 1.02 to 1.99]). Women diagnosed with vaginitis and cervicitis had a higher prevalence of M. genitalium infection than women without those diagnoses, although this was statistically significant only for vaginitis (for vaginitis, OR = 1.88 [95% CI = 1.37 to 2.58]; for cervicitis, OR = 1.42 [95% CI = 0.61 to 2.96]). A diagnosis of urethritis in men was also significantly associated with M. genitalium infection (OR = 2.97; 95% CI = 2.14 to 4.13). Few characteristics distinguished asymptomatic from symptomatic M. genitalium infections. These results from persons seeking care in the United States suggest that M. genitalium infection should be considered in young persons presenting with urogenital symptoms

Early MAVEN Deep Dip campaign reveals thermosphere and ionosphere variability

International audienceThe Mars Atmosphere and Volatile Evolution (MAVEN) mission, during the second of its Deep Dip campaigns, made comprehensive measurements of martian thermosphere and ionosphere composition, structure, and variability at altitudes down to ~130 kilometers in the subsolar region. This altitude range contains the diffusively separated upper atmosphere just above the well-mixed atmosphere, the layer of peak extreme ultraviolet heating and primary reservoir for atmospheric escape. In situ measurements of the upper atmosphere reveal previously unmeasured populations of neutral and charged particles, the homopause altitude at approximately 130 kilometers, and an unexpected level of variability both on an orbit-to-orbit basis and within individual orbits. These observations help constrain volatile escape processes controlled by thermosphere and ionosphere structure and variability

MAVEN observations of the response of Mars to an interplanetary coronal mass ejection

Coupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-Term evolution of the Mars atmosphere

MAVEN observations of the response of Mars to an interplanetary coronal mass ejection

International audienceCoupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-term evolution of the Mars atmosphere

Early MAVEN Deep Dip campaign reveals thermosphere and ionosphere variability

The Mars Atmosphere and Volatile Evolution (MAVEN) mission, during the second of its Deep Dip campaigns, made comprehensive measurements of martian thermosphere and ionosphere composition, structure, and variability at altitudes down to ~130 kilometers in the subsolar region. This altitude range contains the diffusively separated upper atmosphere just above the well-mixed atmosphere, the layer of peak extreme ultraviolet heating and primary reservoir for atmospheric escape. In situ measurements of the upper atmosphere reveal previously unmeasured populations of neutral and charged particles, the homopause altitude at approximately 130 kilometers, and an unexpected level of variability both on an orbit-To-orbit basis and within individual orbits. These observations help constrain volatile escape processes controlled by thermosphere and ionosphere structure and variability