Inflammation and Immune Evasion Coexist in Treponema Pallidum-infected Skin

Syphilis is a systemic, multistage, sexually transmitted infection caused by the highly invasive spirochetal bacterium, Treponema pallidum, subspecies pallidum. In the United States, the annual rate of primary and secondary syphilis (SS) between 2002 and 2016 has increased from 2.1 to 8.7 cases per 100,000.1 Gestational and congenital syphilis cases have also increased in the last few years. There is no evidence of a change in T pallidum susceptibility to penicillin as an explanation for the significant increase in the number of syphilis cases in the United States. It is more likely that changes in risk-taking behavior in the general population are responsible for this change. Although syphilis is easily treatable with penicillin, if left untreated up to one-third of syphilitic patients will go on to have the typical complications associated with tertiary syphilis. It is therefore critically important for clinicians to be well versed in the classic and not so classic dermatologic manifestations of the disease

Studies on Nanoparticle Based Avian Influenza Vaccines to Present Immunogenic Epitopes of the Virus with Concentration on Ectodomain of Matrix 2 (M2e) Protein

Avian influenza is an infectious disease of avian species caused by type A influenza viruses with a significant economic impact on the poultry industry. Vaccination is the main prevention strategy in many countries worldwide. However, available vaccines elicit antibodies against two major surface protein of the virus hemagglutinin (HA) and neuraminidase (NA), where they constantly change by point mutations. Influenza viruses can also easily undergo gene reassortment. Therefore, to protect chickens against new strain of avian influenza virus, as well as control and prevent virus spread among farms, new vaccines needed to be designed which is a tedious, time consuming and expensive. Recently, conserved regions of the influenza genome have been evaluated as possible universal vaccines to eliminate constant vaccine updates based on circulating virus. In this study, peptide nanotechnology was used to generate vaccine nanoparticles that carry the highly conserved external domain of matrix 2 protein (M2e). These nanoparticles presented M2e in monomeric or tetrameric forms, designated as PSC-M2e-CH and BNSC-M2eN-CH, respectively. First, to demonstrate immunogenicity of these nanoparticles, we measured anti-M2e antibody in chickens, particularly when a high dose was applied. Prior to vaccination-challenge study, the challenge dose were determined by oculonasal inoculation of 106 EID50 or 107.7 EID50 of low pathogenicity AI virus HSN2 followed by measuring cloacal and tracheal virus shedding. A biphasic virus shedding pattern was observed with two peaks of virus shedding at days 4 and 8 for both tracheal and cloacal swabs. The chickens infected with 107.7 EID 50 had significant virus shedding as compared with 106 EID50.^ Based on results of mentioned studies, a vaccination-challenge study was conducted by using 75μg of each vaccine construct per inoculation (with and without adjuvant) and higher dose of virus for challenge. BN5C-M2e-CH with adjuvant significantly reduced the tracheal virus shedding compared with the positive challenge control and offered significant protection by expediting clearance of the virus in infected chickens. Reduction in cloacal virus shedding was not significant because cloacal shedding is low by nature. These results demonstrate that nanoparticles are a promising platform for immunogenic epitope delivery and M2e is a promising vaccine candidate against low pathogenicity avian influenza (LPAI) viruses.

A Novel miR-451a isomiR, Associated with Amelanotypic Phenotype, Acts as a Tumor Suppressor in Melanoma by Retarding Cell Migration and Invasion

<div><p>miRNAs are key regulatory small non-coding RNAs involved in critical steps of melanoma tumorigenesis; however, the relationship between sequence specific variations at the 5′ or 3′ termini (isomiR) of a miRNA and cancer phenotype remains unclear. Deep-sequencing and qRT-PCR showed reduced expression of miR-144/451a cluster and most abundant isomiR (miR451a.1) in dysplastic nevi, in-situ and invasive melanomas compared to common nevi and normal skin (n = 101). miRNA in situ hybridization reproducibly confirmed lost miR-451a.1 in melanoma compared to nevus cells or adjacent keratinocytes. Significantly higher expression of miR-451a.1 was associated with amelanotic phenotype in melanomas (n = 47). In contrast, miR-451a was associated with melanotic phenotype, absent pagetoid scatter of intraepidermal melanocytes, superficial spreading histological subtype and tumor inflammation. Sequencing miRNAs from cultured melanocytes with cytoplasmic melanin gradient (light, medium to dark) showed absent miR-451a while revealing other melanin-associated miRNAs, e.g. miR-30b, miR-100 and miR-590 in darkly and let-7a, let-7i and let-7f in lightly to moderately pigmented cultured melanocytes. Ectopic expression of miR-144/451a in melanoma cell lines resulted in markedly higher levels of mature miR-451a.1 than miR451a or miR-144; and significantly retarded cell migration and inhibited invasion in a glucose-sensitive manner. Surprisingly, these effects were not mediated by calcium binding protein 39 (CAB39), a proven miR451a gene target. miR-144/miR-451a cluster is a novel miRNA locus with tumor suppressive activity in melanoma.</p></div

Expressing either miR-211 or miR-451a retarded migration and invasion of melanoma cells.

<p>(a) miR-211 or miR-451a significantly reduced the migration rate of WM983A cells after 48 h in normal glucose (4.5 g/L). (b) Lowering glucose (0.3 g/L) dramatically retarded migration rate of miR-451a or miR-144-transfected WM983A cells after 24 h; expressing both miR-144 and miR-451a together did not result in an added effect of retarded migration. (c) Moreover, expressing either miR-211 or miR-451a reduced the migration rate and (d) invasion of A375SM cells, respectively. (e) Cells transfected with miR-SCR nearly closed the gap by cross migration after 24 h whereas this process was retarded by miR-211 and miR-451a. The error bars represent standard deviation from at least two different independent experiments. *<i>P</i>-value<0.05; **<i>P</i>-value<0.005; ***<i>P</i>-value<0.0005.</p

Expression of miR-144/451a cluster retarded migration of melanoma cells in a glucose sensitive manner.

<p>(a and b) Expressing miR-144/451a significantly decreased migration distance after 6, 12 and 24 h in a glucose-sensitive manner. (c) miR-451a.1 was the most abundant isomiR in scramble transfected (miR-SCR) control cells. (d) Expressing miR-144/451a led to>2000-fold increase in miR-451a.1 whereas (e) expressing miR-451a alone led to>180-fold in miR-451a.1. (f) Similarly, expressing miR451a alone led to>200-fold miR-451a.1 in another cell line (A375SM). (g and h) miR-144/451a did not alter the CAB39 protein levels. The error bars represent standard deviation from at least three different independent experiments. **<i>P</i>-value<0.005; ***<i>P</i>-value<0.0005. qRT-PCR were performed in triplicates.</p

Distribution and expression of miR-451a isomiRs by NGS and qRT-PCR.

<p>(a) miR-451a.1 (isomiR1) was the most abundant sequence among normal skin (NS), primary cutaneous melanoma (PCM), metastatic melanoma to LN (MMLN) and to skin (MMS). (b) In a validation cohort, qRT-PCR showed significantly reduced levels for both miR-451a and miR-451a.1 in PCM compared to NS. miR-451a.1 levels were decreased in DN, MIS and PCM compared to CN. The relative expression was an average RQ values for all samples. qRT-PCR were performed in triplicates for every sample.</p

Higher miR-451a.1 expression was associated with amelanotic phenotype in melanoma.

<p>(a) Based on melanoma intracytoplasmic melanin, PCM biopsies were classified into absent, faint, moderate or abundant. (b) The expression of miR-451a.1 was significantly higher in amelanotic lesions, in contrast to miR-451a (miRBase v18). The numbers shown in the dot-plots are the average RQ values.</p

Decreased expression of miR-451a.1 in primary melanoma by MISH.

<p>(a-f) miR-451a.1 signal (red) was consistently detected in nuclei and cytoplasm of dermal nevus cells, overlying epidermal keratinocytes and epithelium of hair follicle (HF) in 6 representative CN; (g-i) this signal was absent from the nuclei and cytoplasm of dermal melanoma cells in 6 representative PCM. Loss of miR-451a.1 expression was best seen in the melanoma in situ cells (arrow heads) in contrast to surrounding keratinocytes. The solid line represents epidermal-dermal junction. All images were acquired under constant parameters. The original magnification was 200× for all images; inset was 630×.</p