Imidazolyl Ethanamide Pentandioic Acid (IEPA) as Potential Radical Scavenger during Tumor Therapy in Human Hematopoietic Stem Cells

Radiochemotherapy-associated leuco- or thrombocytopenia is a common complication, e.g., in head and neck cancer (HNSCC) and glioblastoma (GBM) patients, often compromising treatments and outcomes. Currently, no sufficient prophylaxis for hematological toxicities is available. The antiviral compound imidazolyl ethanamide pentandioic acid (IEPA) has been shown to induce maturation and differentiation of hematopoietic stem and progenitor cells (HSPCs), resulting in reduced chemotherapy-associated cytopenia. In order for it to be a potential prophylaxis for radiochemotherapy-related hematologic toxicity in cancer patients, the tumor-protective effects of IEPA should be precluded. In this study, we investigated the combinatorial effects of IEPA with radio- and/or chemotherapy in human HNSCC and GBM tumor cell lines and HSPCs. Treatment with IEPA was followed by irradiation (IR) or chemotherapy (ChT; cisplatin, CIS; lomustine, CCNU; temozolomide, TMZ). Metabolic activity, apoptosis, proliferation, reactive oxygen species (ROS) induction, long-term survival, differentiation capacity, cytokine release, and DNA double-strand breaks (DSBs) were measured. In tumor cells, IEPA dose-dependently diminished IR-induced ROS induction but did not affect the IR-induced changes in metabolic activity, proliferation, apoptosis, or cytokine release. In addition, IEPA showed no protective effect on the long-term survival of tumor cells after radio- or chemotherapy. In HSPCs, IEPA alone slightly enhanced CFU-GEMM and CFU-GM colony counts (2/2 donors). The IR- or ChT-induced decline of early progenitors could not be reversed by IEPA. Our data indicate that IEPA is a potential candidate for the prevention of hematologic toxicity in cancer treatment without affecting therapeutic benefits.

Analysis of chicken macrophage functions and gene expressions following infectious bronchitis virus M41 infection

Infectious bronchitis virus (IBV) is a pathogenic coronavirus with high morbidity and mortality in chicken breeding. Macrophages with normal biofunctions are essential for host immune responses. In this study, the HD11 chicken macrophage cell line and chicken peripheral blood mononuclear cell-derived macrophages (PBMCs-Mφ) were infected with IBV at multiplicity of infection (MOI) of 10. The dynamic changes of their biofunctions, including cell viability, pathogen elimination function, phagocytic ability, and gene expressions of related proteins/mediators in innate and acquired immunity, inflammation, autophagy and apoptosis were analyzed. Results showed that IBV infection decreased chicken macrophage viability and phagocytic ability, and increased pathogen elimination function. Moreover, IBV augmented the gene expressions of most related proteins in macrophages involved in multiple host bioprocesses, and the dynamic changes of gene expressions had a close relationship with virus replication. Among them, MHCII, Fc receptor, TLR3, IFN-α, CCL4, MIF, IL-1β, IL-6, and iNOS showed significantly higher expressions in IBV-infected cells. However, TLR7, MyD88, MDA5, IFN-γ, MHCII, Fc receptor, MARCO, CD36, MIF, XCL1, CXCL12, TNF-α, iNOS, and IL-10 showed early decreased expressions. Overall, chicken macrophages play an important role in host innate and acquired immune responses to resist IBV infection, despite early damage or suppression. Moreover, the IBV-induced autophagy and apoptosis might participate in the virus-host cell interaction which is attributed to the biological process.

[Pharmacotherapy for acute respiratory infections caused by influenza viruses: current possibilities]

Routinely the influenza virus significantly contributes to the formation of the annual incidence of acute respiratory infections, with a peak in winter season. The high level of mutagenic potential of influenza viruses is a standard factor determining the complexity of the rational choice of pharmacotherapy. The upcoming epidemiological season 20202021 brings additional challenges for health care practitioners mediated by the widespread prevalence in the human population of a new infection caused by the SARS-CoV-2 virus affecting the respiratory system among many organs and systems. An adequate choice of pharmacotherapy tools should be based on high efficiency and safety of drugs, with a possible reduction in such negative factors as polypharmacy. This review includes comparative pharmacological characteristics of drugs with activity against RNA viruses, along with parameters of their clinical efficacy.

Some opportunities for immunotherapy in coronavirus infection

Here we review means of immunomodulatory therapy for coronavirus infection caused by SARS-CoV-2 (COVID-19). It has been appreciated that highly limited arsenal of relatively effective means and methods of prevention and treatment of the COVID-19 pandemic is available. The goal of our study was to analyze some therapeutic approaches based on available publications for COVID-19 treatment viewed from acting via innate immunity system. Convalescent plasma serotherapy represents one of the means with verified therapeutic efficacy that was accompanied with decreased viral load and relief of the disease symptoms. The drawback of serotherapy results from limited number of potential plasma donors and profound variety in amount of SARS-CoV-2-specific antibodies found in donor plasma. Another approach to COVID-19 therapy is based on using monoclonal antibodies engineered to target specific virus antigenic determinants, most often surface spike antigen. Antibodies blocking such antigen are able to prevent virus entrance into target cells and development of overt infection. On the other hand, there are monoclonal antibodies abrogating production or binding of excessive amounts of pro-inflammatory cytokines, such as IL-6, TNFα, etc., some of which (tocilizumab) have been already tested in COVID-19 therapy, whereas the remaining preparations are being currently investigated and tested. A certain breakthrough in COVID-19 therapy was provided by the well-known drugs chloroquine and dihydrochloroquine, which have proven to be effective as antiviral, anti-inflammatory and immunomodulatory means. Finally, a new multicomponent immunomodulatory preparation Cytovir-3 has been proposed already passed clinical trials and recommended for use in prevention and treatment of influenza and SARS and might have found its own niche in preventing COVID-19, as SARS-CoV-2 also belongs to the group of acute respiratory viruses. Thus, the arsenal of means for COVID-19 prevention and treatment contains the drugs for immunomodulatory therapy and prevention of immune-related disorders developing in response to invasion pathogenic viruses and lowering a risk of possible damage. Hence, correct and scientifically justified use of such remedies will increase overall effectiveness of fight against the coronavirus pandemic.