Humanized Mouse Model of HIV Infection Leontyev, D. S.; Glazkova, D. V.; Bezborodova, O. A. ...
Bulletin of experimental biology and medicine,
05/2023, Letnik:
175, Številka:
1
Journal Article
Recenzirano
The development of new drugs for the treatment of HIV infection requires testing of their efficacy in a relevant animal model, such as humanized mice, which, unfortunately, are not yet available in ...Russia. In the present study, we have developed conditions for the humanization of immunodeficient NSG mice with human hematopoietic stem cells. Humanized animals generated during the study showed a high degree of chimerism and harbored repopulation of the entire range of human lymphocytes required for HIV replication in the blood and organs. Inoculation of these mice with HIV-1 virus led to stable viremia, which was confirmed by the presence of viral RNA in blood plasma throughout the entire period of observation and proviral DNA in the organs of animals 4 weeks after HIV infection.
•Novel single-tube real-time PCR to determine a ratio of wild type and rMVA in plaques.•Rapid generation of new pure rMVA in 11 days.•Plaque purification is less effective then end-point dilution as ...the last purification step.•Various marker gene selected plaques differ greatly in proportion of rMVA.
Obtaining a pure recombinant Modified Vaccinia Ankara (MVA) virus is a multistage, time-consuming procedure. We describe a novel single-tube real-time PCR which enables determination of the amount of wild type and recombinant viruses and their ratio in plaques. Use of the real-time PCR significantly reduce the time and efforts needed to obtain purified recombinant MVA. The new approach has been applied to generate recombinant MVAs encoding different SARS-COV-2 antigens.
We studied the effectiveness of photodynamic therapy with the photosensitizer Photoran E6 on the model of rat sarcoma M-1 positive for mutant
p53
gene. Experiments showed that Photoran E6 exhibits ...high antitumor activity in photodynamic therapy of solid tumor of the connective tissue. Photodynamic therapy carried out during the optimal period after injections of Photoran E6 with the determined parameters of laser exposure allows achieving the maximum inhibitory effect on sarcoma M-1: 100% cured animals. Immunohistochemical study revealed no live tumor cells with expression of the mutant p53 protein in areas of photodynamic exposure.
The chimeric protein TRIM5α-HRH is a promising antiviral factor for HIV-1 gene therapy. This protein is able to protect cells from HIV-1 by blocking the virus in the cytoplasm. We are developing ...protocol of HIV-1 gene therapy, which involves the delivery of the TRIM5α-HRH gene into CD4^(+) T-lymphocytes by lentiviral vectors (LVs). However, LVs containing TRIM5α-HRH have a low infectious titer, which prevents effective T cell modification. Here, we found that the expression of TRIM5α-HRH during pseudoviral particle production in HEK293 T cells, as well as the presence of the Eflα promoter in our construction are responsible for titer reduction. These results allow us to determine the directions for further optimization of LV with the TRIM5α-HRH gene to improve its infectious titer.
The chimeric protein TRIM5α-HRH is a promising antiviral factor for HIV-1 gene therapy. This protein is able to protect cells from HIV-1 by blocking the virus in the cytoplasm. We are developing ...protocol of HIV-1 gene therapy, which involves the delivery of the
TRIM5
α
-HRH
gene into CD4
+
T-lymphocytes by lentiviral vectors (LVs). However, LVs containing
TRIM5
α
-HRH
have a low infectious titer, which prevents effective T cell modification. Here, we found that the expression of
TRIM5
α
-HRH
during pseudoviral particle production in HEK293 T cells, as well as the presence of the Ef1α promoter in our construction are responsible for titer reduction. These results allow us to determine the directions for further optimization of LV with the
TRIM5
α
-HRH
gene to improve its infectious titer.
Gene therapy is considered a promising approach to treating infections caused by human immunodeficiency virus (HIV). One strategy is to introduce antiviral genes into cells in order to impart ...resistance to HIV. In this work, the antiviral activity of new anti-HIV lentiviral vector
pT
has been studied. The vector carries a combination that consists of two identical artificial miRNA mic13lg and the
TRIM5α-HRH
gene. Two mic13lg microRNAs suppress the expression of the
CCR5
gene, which encodes the HIV coreceptor and, thus, prevents the penetration of R5-tropic HIV strains into the cell. It has been shown that pT effectively inhibits the expression of
CCR5
in both the HT1080 CCR5-EGFP model cell line and in human primary lymphocytes. The second line of protection against R5- and X4-tropic HIV is provided by the TRIM5α-HRH protein, which binds virus capsids after the virus enters the cell. Indeed, when infecting cells of the SupT1 line, which contains four copies of the vector per cell, with the X-4 tropic HIV, more than 1000-fold suppression of viral replication has been observed. The process of generation of the
pT
vector and conditions of transduction of CD4
+
lymphocytes were optimized for testing the antiviral activity of the vector on primary human lymphocytes. As a result, the transduction efficiency for the
pT
vector was 28%. After infection with the R5-tropic strain of the virus, the survival of cells in the culture of lymphocytes with the vector was significantly higher than in the control. However, the complete suppression of HIV replication was not achieved, presumably due to the inadequate fraction of cells that carry the vector in culture. In the future, it is planned to find the best way to enrich the lymphocyte culture with modified cells to increase resistance to HIV.
In this paper, a gradient-based adaptive filtering technique for unknown state and parameter estimation is proposed for some extensions of classical state-space models: (i) linear time-invariant ...multiple-input, multiple-output (LTI MIMO) systems, and (ii) linear pairwise Markov models (PMMs) with the related pairwise Kalman filter (PKF). The solution to robust adaptive filtering problem is grounded in the singular value decomposition (SVD) recently adopted for the classical Kalman filter. In contrast to our previous result, the new methods are designed for the case of thin matrices (pre-arrays) involved in the filtering recursions and sensitivities calculation. Additionally, the paper discusses a time-varying variance models’ calibration by the proposed innovative adaptive filters. In particular, the state-space approach for estimating GARCH-in-Mean(1,1) is explored.
Gene therapy is considered a promising approach to treating infections caused by human immunodeficiency virus (HIV). One strategy is to introduce antiviral genes into cells in order to impart ...resistance to HIV. In this work, the antiviral activity of new anti-HIV lentiviral vector pT has been studied. The vector carries a combination that consists of two identical artificial miRNA mic13lg and the TRIM5α-HRH gene. Two mic13lg microRNAs suppress the expression of the CCR5 gene, which encodes the HIV coreceptor and, thus, prevents the penetration of R5-tropic HIV strains into the cell. It has been shown that pT effectively inhibits the expression of CCR5 in both the HT1080 CCR5-EGFP model cell line and in human primary lymphocytes. The second line of protection against R5- and X4-tropic HIV is provided by the TRIM5α-HRH protein, which binds virus capsids after the virus enters the cell. Indeed, when infecting cells of the SupT1 line, which contains four copies of the vector per cell, with the X-4 tropic HIV, more than 1000-fold suppression of viral replication has been observed. The process of generation of the pT vector and conditions of transduction of CD4^(+) lymphocytes were optimized for testing the antiviral activity of the vector on primary human lymphocytes. As a result, the transduction efficiency for the pT vector was 28%. After infection with the R5-tropic strain of the virus, the survival of cells in the culture of lymphocytes with the vector was significantly higher than in the control. However, the complete suppression of HIV replication was not achieved, presumably due to the inadequate fraction of cells that carry the vector in culture. In the future, it is planned to find the best way to enrich the lymphocyte culture with modified cells to increase resistance to HIV.
Since its beginnings in 2019, the COVID-19 pandemic is still a problem of global medical concern. Southern Vietnam is one of the country's vast regions, including 20 provinces and the densely ...populated metropolis Ho Chi Minh City. A randomized retrospective study was performed to investigate the epidemiology and genetic diversity of COVID-19. Whole-genome sequencing of 126 SARS-CoV-2 samples collected from Southern Vietnam between January 2020 and December 2021 revealed the main circulating variants and their distribution.
Epidemiological data were obtained from the Department of Preventive Medicine of the Vietnamese Ministry of Health. To identify circulating variants, RNA, extracted from 126 nasopharyngeal swabs of patients with suspected COVID-19 were sequenced on Illunina MiSeq to obtain near complete genomes SARS-CoV-2.
Due to the effectiveness of restrictive measures in Vietnam, it was possible to keep incidence at a low level. The partial relaxation of restrictive measures, and the spread of Delta lineages, contributed to the beginning of a logarithmic increase in incidence. Lineages 20A-H circulated in Southern Vietnam during 2020. Spread of the Delta lineage in Southern Vietnam began in March 2021, causing a logarithmic rise in the number of COVID-19 cases.
Pandemic dynamics in Southern Vietnam feature specific variations in incidence, and these reflect the success of the restrictive measures put in place during the early stages of the pandemic.
