Search

Following viral infection, antigen-restricted T lymphocytes are activated and recognize infected cells to eliminate them. A subset of T cells differentiates into memory lymphocytes able to counteract viral rechallenge in a faster and enhanced way. SARS-CoV-2 can escape immune responses leading to a poor clinical outcome. Immune escape can be associated with the failure of the development of T cell memory compartments. The aim of this study is to characterize the T memory subsets and to test the immune response against class I- and II-restricted immunodominant epitopes shared by ancestral and SARS-CoV-2 variants strains. T memory subsets and recognition of SARS-CoV-2S Spike-specific epitopes were analyzed by flow cytometry on 14 fully vaccinated healthy donors (HDV) and 18 COVID-19 recovered patients (CD). The results obtained showed that CD8+ T naïve subset numbers decreased in association with a significant increase of the effector memory T cell subset whereas there was a small increase in the percentage of SARS-CoV-2 antigen-restricted T clones in both CD4 + and CD8+ subset in the CD compared to HDV sample. Collectively, these features may reflect a broader cytotoxic T cell repertoire stimulated by the virus during the natural infection compared to the spike-restricted response activated during vaccination.

Coronavirus disease 2019 (COVID-19) is an infection characterized by the dysregulation of systemic cytokine levels. The measurement of serum levels of inflammatory cyto-/chemokines has been suggested as a tool in the management of COVID-19. The aim of this study is to highlight the significance of measured levels of interleukin (IL)-1α, IL-1β, IL-6, IL-8, IL-10, IL-12(p70), IL-27, interferon (IFN)γ, interferon gamma-induced protein (IP)-10, monocyte chemoattractant protein (MCP)-1, and tumor necrosis factor (TNF)-α in serum samples from infected and recovered subjects, possibly predictive of severity and/or duration of the disease. Serum samples from healthy (HD), positive at hospital admittance (T0), and recovered subjects (T1, 31-60, or 70-200 days post-negativization) were collected and tested through a bead-based cytometric assay and confirmed through ELISA. IL-10 levels were increased in the T0 group compared to both HD and T1. IL-27 significantly decreased in the 31-60 group. IL-1β significantly increased in the 70-200 day group. TNF-α significantly decreased in T0 compared to HD and in the 31-60 group versus HD. IP-10 significantly increased in T0 compared to HD. These results suggest that IP-10 could represent an early marker of clinical worsening, whereas IL-10 might be indicative of the possible onset of post-COVID-19 long syndrome.

Actinic keratosis (AK) is a carcinoma in situ precursor of cutaneous squamous cell carcinoma (cSCC), the second most common cancer affecting the Caucasian population. AK is frequently present in the sun-exposed skin of the elderly population, UV radiation being the main cause of this cancer, and other risk factors contributing to AK incidence. The dysregulation of microRNAs (miRNAs) observed in different cancers leads to an improper expression of miRNA targets involved in several cellular pathways. The TaqMan Array Human MicroRNA Card assay for miRNA expression profiling was performed in pooled AK compared to healthy skin scraping samples from the same patients. Forty-three miRNAs were modulated in the AK samples. The expression of miR-19b ( p < 0.05), -31, -34a ( p < 0.001), -126, -146a ( p < 0.01), -193b, and -222 ( p < 0.05) was validated by RT-qPCR. The MirPath tool was used for MiRNA target prediction and enriched pathways. The top DIANA-mirPath pathways regulated by the targets of the 43 miRNAs are TGF-beta signaling, Proteoglycans in cancer, Pathways in cancer, and Adherens junction (7.30 × 10 -10 < p < 1.84 × 10 -8 ). Selected genes regulating the KEGG pathways, i.e., TP53 , MDM2 , CDKN1A , CDK6 , and CCND1 , were analyzed. MiRNAs modulated in AK regulate different pathways involved in tumorigenesis, indicating miRNA regulation as a critical step in keratinocyte cancer.

Background: The β3 human papillomavirus (HPV)49 induces immortalization of primary keratinocytes through the action of E6 and E7 oncoproteins with an efficiency similar to alpha high risk (HR)-HPV16. Since HR-HPV oncoproteins are known to alter microRNA (miRNA) expression and extracellular vesicle (EV) production, we investigated the impact of HPV49 E6 and E7 proteins on miRNA profile and EV expression, and their involvement in the control of cell proliferation., Methods: The miRNA expression was evaluated by a miRNA array and validated by RT-qPCR in primary human keratinocytes immortalized by β3 HPV49 (K49) or α9 HR-HPV16 (K16), and in EVs from K49 and K16. The modulation of miRNA target proteins was investigated by immunoblotting analyses., Results: By comparing miRNA expression in K49 and K16 and the derived EVs, six miRNAs involved in HPV tumorigenesis were selected and validated. MiR-19a and -99a were found to be upregulated and miR-34a downregulated in both cell lines; miR-17 and -590-5p were upregulated in K49 and downmodulated in K16; miR-21 was downregulated only in K16. As for EV-carried miRNAs, the expression of miR-17, -19a, -21 and -99a was decreased and miR-34a was increased in K49 EVs. In K16 EVs, we revealed the same modulation of miR-19a, -34a, and -99a observed in producing cells, while miR-21 was upregulated. Cyclin D1, a common target of the selected miRNAs, was downmodulated in both cell lines, whereas cyclin-dependent kinase 4 was down-modulated in K49 but upregulated in K16., Conclusion: These data suggest that E6 and E7 proteins of β3 HPV49 and α9 HR-HPV16 affect key factors of cell cycle control by indirect mechanisms based on miRNA modulation., (© 2022. The Author(s).)