Cell and Organism Technologies for Assessment of the SARS-CoV-2 Infectivity in Fluid Environment.

Under conditions of COVID-19 pandemic, considerable amounts of SARS-CoV-2 contained in household, municipal, and medical wastewaters inevitably reach natural water bodies. Possible preservation of virus infectivity in liquid environment is of a paramount epidemiological importance. Experiments demonstrated that SARS-CoV-2 is resistant to multiple freezing/thawing cycles and retains its infectivity in tap and river water for up to 2 days at 20°C and 7 days at 4°C.

Messenger RNA of the Histidine-Rich Glycoprotein in Breast Tumors.

The content of mRNA of the histidine-rich glycoprotein (HRG), a potential marker of malignant neoplasia, which can be used in differential diagnosis of breast tumors, was determined in 110 breast tumor biopsy samples. The presence of HRG mRNA did not depend on the cancer type, on the preoperative treatment or its absence, as well as on the tumor progression stage and the presence of metastases.

Cytokine production in mammary adenocarcinoma and its microenvironmental cells in patients with or without metastases in regional lymph nodes.

In recent years, the concept of formation of a sufficiently autonomous cytokine network in a malignant tumour has emerged. In this regard, the data on the role of this network and its signalling pathways in the process of metastasis are an interesting topic. The aim of this study was to evaluate the in vitro cytokine-producing potential of mammary adenocarcinoma (MAC; and cells of its microenvironment) from patients with or without metastases in regional lymph nodes (LNs).

[The tick-borne encephalitis virus detection efficiency in the Ixodid ticks (Acari: Ixodidae) with ELISA and real-time PCR].

According to the data of the Federal Service on Customers' Rights Protection and Human Well-being Surveillance, the enzyme-linked immunosorbent assay (ELISA) detects the tick-borne encephalitis virus (TBEV) in ticks more often than the polymerase chain reaction (PCR). The goal of this work was to compare TBEV detection efficiency in the ixodid ticks of different species with the commercial kits based on ELISA and real-time PCR. Ticks of five species were parenterally infected with 2-6 IgPFU of the European or Siberian TBEV subtypes.

An atomic force microscopy study in the detection of hepatitis B surface antigen by enzyme-linked immunosorbent assay.

Atomic force microscopy (AFM) was employed to study certain enzyme immunoassay steps for the detection of hepatitis B surface antigen (HBsAg). Physical adsorption of monoclonal antibodies (mAb), blocking of surface active sites free of antibodies by neutral proteins, and capture of HBsAg particles by sensitized surfaces were visualized successively in microplate wells of standard immunological plates from various manufacturers. The previously undescribed details such as "etching holes" up to 20 nm in depth were observed on the surface of plates some companies.

[Humoral factors of immunity and the mononuclear cell responses to fetoproteins in patients with pulmonary tuberculosis].

The content of cytokines, the levels of antibodies (Ab) to proinflammatory cytokines and fetoproteins (FP) in serum, as well as the effects of fitohemagglutinin and FP on the level of cell production of cytokines into the conditioned medium were studied in relation to the pattern of a response of mononuclear cells (MNC) to FP. With the positive reaction of MNC to FP, estimated by an increment of CD9* cells and detectable in grades 2-3 dysplasias, the anti-inflammatory effect with lower anti-inflammatory cytokines was shown to be achieved due to elevated Ab levels, which may compensate for the low content of IL-4 and IL-10. With FP, there was an increase in the cell production of IL-10 that is known to stimulate antibody formation in the early phase of tumor growth, as evidenced by the association of the levels of Ab to FP with the grade of dysplasia.

[Production and characterization of a panel of monoclonal antibodies to Toxoplasma gondii antigens].

A representative collection was obtained containing 68 monoclonal antibodies (MAB) to Toxoplasma gondii antigens, which was characterized by the binding with the below fractions of tochizoites in the immune-enzyme assay (IEA) and immunoblotting (IB): membrane (MEM), somatic (water-soluble, SOM) and excretory-secretory (ES). Most of MABs were produced to MEM antigens (43), 6 MABs reacted with the somatic fraction, and 3 MABs reacted with both fractions. Two MABs to ES antigen were detected in the latter group.

[Construction and expression in Escherichia coli of a gene of hybrid hemagglutinin H1-H3 of influenza virus].

The hybrid gene of influenza virus hemagglutinin (HA) of the H1-subtype, carrying the sequence coding for the fragment of H3-subtype antigenic site B, was constructed. The product of expression of this gene in E. coli was obtained as a fusion protein with beta-galactosidase.

[Cloning and expression of the hemagglutinin gene of influenza virus subtype H1 in Escherichia coli].

The full-length copy of the hemagglutinin gene of influenza virus was inserted into M13 phage DNA. The DNA sequence coding for the hydrophobic prepeptide was removed from the gene by oligonucleotide-directed mutagenesis. The possibilities of expression of the full-length and mutant genes in E.