CD57 Expression and Cytokine Production by T Cells in Lesional and Unaffected Skin from Patients with Psoriasis

Background

The immunopathogenic mechanisms leading to psoriasis remain unresolved. CD57 is a marker of replicative inability and immunosenescence on CD8+ T cells and the proportion of CD57 expressing CD8+ T cells is increased in a number of inflammatory conditions.

Methodology

We examined the expression of CD57 on T cells in the skin of patients affected with psoriasis, comparing lesional and unaffected skin. We also assessed functionality of the T cells by evaluating the secretion of several inflammatory cytokines (IL-17A, IFN-gamma, IL-2, IL-33, TNF-alpha, IL-21, IL-22, and IL-27), from cell-sorted purified CD4+ and CD8+ T cells isolated from lesional and unaffected skin biopsies of psoriasis patients.

Principal Findings

We observed that the frequency of CD57+CD4+ and CD57+CD8+ T cells was significantly higher in unaffected skin of psoriasis patients compared to lesional skin. Sorted CD4+ T cells from psoriatic lesional skin produced higher levels of IL-17A, IL-22, and IFN-gamma compared to unaffected skin, while sorted CD8+ T cells from lesional skin produced higher levels of IL-17, IL-22, IFN-gamma, TNF-alpha, and IL-2 compared to unaffected skin.

Conclusions/Significance

These findings suggest that T cells in unaffected skin from psoriasis patients exhibit a phenotype compatible with replicative inability. As they have a lower replicative capacity, CD57+ T cells are less frequent in lesional tissue due to the high cellular turnover.     

Alginate Oligosaccharides Inhibit Fungal Cell Growth and Potentiate the Activity of Antifungals against Candida and Aspergillus spp

The oligosaccharide OligoG, an alginate derived from seaweed, has been shown to have anti-bacterial and anti-biofilm properties and potentiates the activity of selected antibiotics against multi-drug resistant bacteria. The ability of OligoG to perturb fungal growth and potentiate conventional antifungal agents was evaluated using a range of pathogenic fungal strains. Candida (n = 11) and Aspergillus (n = 3) spp. were tested using germ tube assays, LIVE/DEAD staining, scanning electron microscopy (SEM), atomic force microscopy (AFM) and high-throughput minimum inhibition concentration assays (MICs). In general, the strains tested showed a significant dose-dependent reduction in cell growth at ≥6% OligoG as measured by optical density (OD₆₀₀; P<0.05). OligoG (>0.5%) also showed a significant inhibitory effect on hyphal growth in germ tube assays, although strain-dependent variations in efficacy were observed (P<0.05). SEM and AFM both showed that OligoG (≥2%) markedly disrupted fungal biofilm formation, both alone, and in combination with fluconazole. Cell surface roughness was also significantly increased by the combination treatment (P<0.001). High-throughput robotic MIC screening demonstrated the potentiating effects of OligoG (2, 6, 10%) with nystatin, amphotericin B, fluconazole, miconazole, voriconazole or terbinafine with the test strains. Potentiating effects were observed for the Aspergillus strains with all six antifungal agents, with an up to 16-fold (nystatin) reduction in MIC. Similarly, all the Candida spp. showed potentiation with nystatin (up to 16-fold) and fluconazole (up to 8-fold). These findings demonstrate the antifungal properties of OligoG and suggest a potential role in the management of fungal infections and possible reduction of antifungal toxicity.     

The presence of enkephalin-like substances in the eyestalk and brain of the land crabGecarcinus lateralis

The eyestalk of the land crab, Gecarcinus lateralis, is rich in Met-enkephalin-like materials. Leu-enkephalin, if present, is at a level which is below the sensitivity of our assay. The brain (cerebral ganglion) of this organism contains both Met- and Leu-enkephalin-like materials. Material which was reactive with our Met-enkephalin antibody was also detected in a peak that migrated after Leu-enkephalin. This biochemical study confirms earlier immunohistochemical reports which indicated that opioid substances are present in crustaceans. It also strongly supports the concept that opioid mechanisms are a product of early evolution and further demonstrates that the sequence of the smaller opioid compounds has been conserved.     

Kinetics and interaction studies between cytochrome c3 and Fe-only hydrogenase from Desulfovibrio vulgaris hildenborough

Hydrogenases from Desulfovibrio are found to catalyze hydrogen uptake with low potential multiheme cytochromes, such as cytochrome c₃, acting as acceptors. The production of Fe-only hydrogenase from Desulfovibrio vulgaris Hildenborough was improved with respect to the growth phase and media to determine the best large-scale bacteria growth conditions. The interaction and electron transfer from Fe-only hydrogenase to multiheme cytochrome has been studied in detail by both BIAcore and steady-state measurements. The electron transfer between [Fe] hydrogenase and cytochrome c₃ appears to be a cooperative phenomenon (h = 1.37). This behavior could be related to the conductivity properties of multihemic cytochromes. An apparent dissociation constant was determined (2 × 10^-7 M). The importance of the cooperativity for contrasting models proposed to describe the functional role of the hydrogenase/cytochrome c₃ complex is discussed. Presently, the only determined structure is from [NiFe] hydrogenase and there are no obvious similarities between [NiFe] and [Fe] hydrogenase. Furthermore, no crystallographic data are available concerning [Fe] hydrogenase. The first results on crystallization and X-ray crystallography are reported. Proteins 33:590–600, 1998. © 1998 Wiley-Liss, Inc.     

17O]oxygen hyperfine structure for the hydroxyl and superoxide radical adducts of the spin traps DMPO, PBN and 4-POBN

[17O]oxygen hyperfine coupling constants are reported for the superoxide and hydroxyl radical adducts with the spin traps 5,5-dimethyl-1-pyrroline N-oxide, N-t-butyl-alpha-phenylnitrone and alpha-(4-pyridyl 1-oxide)-N-t-butylnitrone. These couplings provide spectroscopic evidence that the spin adducts have been correctly identified.     

Towards a modern definition of vitamin E-evidence for a quinone hypothesis

We report on the synthesis, biological and pharmacological activity of the tocoquinone natural product, α-tocopherol quinone (ATQ); an oxidative metabolite of α-tocopherol. ATQ is a potent cellular protectant against oxidative stress, whose biological activity is dependent upon its ability to undergo reversible two-electron redox cycling. ATQ is orally bioavailable, with a favorable pharmacokinetic profile and has demonstrated a beneficial clinical response in patients with Friedreich's ataxia. ATQ is a member of a broader class of vitamin E derived quinone metabolites which may be ascribable in whole or in part to the activity of vitamin E.     

Linking Mosquito Infestation to Resident Socioeconomic Status, Knowledge, and Source Reduction Practices in Suburban Washington, DC

Eliminating water-holding containers where mosquitoes oviposit and develop (source reduction) can help manage urban disease-vector mosquitoes. Source reduction requires residents to be knowledgeable of effective practices and motivated to implement them. We tested relationships between demographics, resident knowledge, attitudes, and practices (KAP), and mosquito infestation by administering larval mosquito surveys and KAP questionnaires in Washington, DC. Respondents who reported practicing source reduction had lower numbers of pupae-positive containers and Culex pipiens-positive containers, but not Aedes albopictus-positive containers or water-holding containers, in their yards. When controlling for numbers of water-holding containers in statistical models, residents who reported source reduction had lower numbers of A. albopictus-positive containers in addition to numbers of pupae-positive containers and C. pipiens-positive containers. These results suggest that while active container reduction may be effective at reducing C. pipiens and overall pupal production, it may be offset by other resident activities that add containers to yards, and that source reduction that involves mosquito habitat management without outright container removal can also be effective at reducing A. albopictus. Source reduction was related to respondent knowledge of mosquitoes and, in particular, specific knowledge of mosquito development, which both varied with demographics alongside respondent motivation to control mosquitoes. Respondents from high socioeconomic status households reported greater knowledge but lower motivation than respondents from middle and low socioeconomic-status households. We conclude that mosquito-related education will help promote community-based container management as part of integrated mosquito management programs, particularly in middle and low socioeconomic status neighborhoods with lower knowledge and high motivation.     

Very high density of Chinese hamster ovary cells in perfusion by alternating tangential flow or tangential flow filtration in WAVE bioreactor™—part II: Applications for antibody production and cryopreservation

A high cell density perfusion process of monoclonal antibody (MAb) producing Chinese hamster ovary (CHO) cells was developed in disposable WAVE Bioreactor? using external hollow fiber (HF) filter as cell separation device. Tangential flow filtration (TFF) and alternating tangential flow (ATF) systems were compared and process applications of high cell density perfusion were studied here: MAb production and cryopreservation. Operations by perfusion using microfiltration (MF) or ultrafiltration (UF) with ATF or TFF and by fed‐batch were compared. Cell densities higher than 10⁸ cells/mL were obtained using UF TFF or UF ATF. The cells produced comparable amounts of MAb in perfusion by ATF or TFF, MF or UF. MAbs were partially retained by the MF using ATF or TFF but more severely using TFF. Consequently, MAbs were lost when cell broth was discarded from the bioreactor in the daily bleeds. The MAb cell‐specific productivity was comparable at cell densities up to 1.3 × 10⁸ cells/mL in perfusion and was comparable or lower in fed‐batch. After 12 days, six times more MAbs were harvested using perfusion by ATF or TFF with MF or UF, compared to fed‐batch and 28× more in a 1‐month perfusion at 10⁸ cells/mL density. Pumping at a recirculation rate up to 2.75 L/min did not damage the cells with the present TFF settings with HF short circuited. Cell cryopreservation at 0.5 × 10⁸ and 10⁸ cells/mL was performed using cells from a perfusion run at 10⁸ cells/mL density. Cell resuscitation was very successful, showing that this system was a reliable process for cell bank manufacturing. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:768–777, 2013