Viruses can persist in differentiated cells (i.e., macrophages) over long periods of time, altering host cells functions but not inducing their death. We had previously reported that, in early passages (14–40) of a murine macrophage-like cell line persistently infected with respiratory syncytial virus (RSV) (MfP), FcgR-mediated phagocytosis and expression of FcgRIIB/RIII on the cell membrane were increased with respect to mock-infected macrophages (MfN). In this work, we explored the mechanism underlying such effects. Increases in FcgR expression and FcgR-mediated phagocytosis are preserved after more than 87 passages of the persistently infected culture. We analyzed the expression of FcgR isoforms at both mRNA and protein levels, and found out that RSV persistence distinctly affects the expression of FcgR isoforms. We also observed that the increase in FcgRs expression results neither from soluble factors (cytokines) or viral products released by the infected cells, nor from an increase in the rate of FcgR internalization. Our results suggest that RSV persistence in macrophages induce intracellular effects that have an impact on FcgRs gene expression at both mRNA and protein levels, and that the characteristics of RSV persistence were preserved for over 87 passages.

Giardia lamblia is a flagellated protozoan responsible for giardiasis, a worldwide diarrheal disease. The adverse effects of the pharmacological treatments and the appearance of drug resistance have increased the rate of therapeutic failures. In the search for alternative therapeutics, drug repositioning has become a popular strategy. Acetylsalicylic acid (ASA) exhibits diverse biological activities through multiple mechanisms. However, the full spectrum of its activities is incompletely understood. In this study we show that ASA displayed direct antigiardial activity and affected the adhesion and growth of trophozoites in a time-dose-dependent manner. Electron microscopy images revealed remarkable morphological alterations in the membrane, ventral disk, and caudal region. Using mass spectrometry and real-time quantitative reverse transcription (qRT-PCR), we identified that ASA induced the overexpression of heat shock protein 70 (HSP70). ASA also showed a significant increase of five ATP-binding cassette (ABC) transporters (giABC, giABCP, giMDRP, giMRPL and giMDRAP1). Additionally, we found low toxicity on Caco-2 cells. Taken together, these results suggest an important role of HSPs and ABC drug transporters in contributing to stress tolerance and protecting cells from ASA-induced stress.

Virus-like particles are excellent inducers of the adaptive immune response of humans and are presently being used as scaffolds for the presentation of foreign peptides and antigens derived from infectious microorganisms for subunit vaccine development. The most common approaches for peptide and antigen presentation are translational fusions and chemical coupling, but some alternatives that seek to simplify the coupling process have been reported recently. In this work, an alternative platform for coupling full antigens to virus-like particles is presented. Heterodimerization motifs inserted in both Tobacco etch virus coat protein and green fluorescent protein directed the coupling process by simple mixing, and the obtained complexes were easily taken up by a macrophage cell line.

Although ART leads to viral suppression, people living with HIV (PLWH) still face an increased risk of comorbidities, such as cancer. The HIV-1 Tat protein may contribute to the promotion of chronic inflammation, oxidative stress, and genomic instability. While the presence of anti-Tat antibodies has been associated with slower disease progression, their potential role in modulating DNA damage remains unclear. Assess the effect of anti-Tat antibodies on cytotoxic and DNA damage in PLWH. A cross-sectional study was conducted in 178 PLWH. Serum anti-Tat IgG antibodies were measured using enzyme-linked immunosorbent assay (ELISA). Cytotoxicity and DNA damage were assessed via serum 8-hydroxy-2′-deoxyguanosine (8-OHdG) and nuclear anomalies (Micronucleus cytome assay) in 2000 buccal cells. Statistical significance was considered at p < 0.05. Anti-Tat antibodies were found in 24.2% of participants. Positive individuals had lower CD4+ T cell counts (p = 0.045) and higher levels of pyknosis (p = 0.0001). No differences in 8-OHdG were found, but 8-OHdG correlated positively with CD4+ counts (rho = 0.334, p = 0.006). Pyknosis negatively correlated with CD4+ counts (rho = −0.272, p = 0.027). Anti-Tat antibodies may not prevent DNA damage but could be related to cytotoxic effects in PLWH.

During the COVID-19 pandemic, the circulation of non–SARS-CoV-2 respiratory viruses changed throughout the world. This study aimed to analyze the effect of respiratory syncytial virus (RSV), metapneumovirus (MPV), rhinovirus (RV), and parainfluenza (PIV)-3 single infection, dual co-infection, and viral load on cytokine and chemokine expression in 300 Mexican patients with ARIs negative for SARS-CoV-2. Molecular detection and viral load were performed by RT-qPCR. Cytokine and chemokine expression was determined in samples positive for single RSV, MPV, RV, or PIV-3 infection, and in the most frequent dual co-infections, by a cytokine panel using a magnetic-bead-based multiplex immunoassay. Of the patients positive for viral infection, 91.7% had a single infection and 8.3% had dual co-infections. In this study, RSV was the respiratory virus with the highest prevalence, and the most common dual co-infection was RV+RSV. On the other hand, RV infections had the highest viral loads compared to the other viruses detected. FGF basic, MIP-1α IL-8, IP-10, MCP-1, IFN-γ, and RANTES showed differential expression between single infections and dual co-infections compared to healthy patients. We report, for the first time, the circulation of non-SARS-CoV-2 viruses in the south of Mexico and the cytokine and chemokine profiles associated with these viruses.