Inhibition of caspase-1-dependent apoptosis suppresses peste des petits ruminants virus replication

Lingxia Li,Shengqing Li,Shengyi Han,Pengfei Li,Guoyu Du,Jinyan Wu,Xiaoan Cao,Youjun Shang 대한수의학회 2023 Journal of Veterinary Science Vol.24 No.5

Background: Peste des petits ruminants (PPR), caused by the PPR virus (PPRV), is an acute and fatal contagious disease that mainly infects goats, sheep, and other artiodactyls. Peripheral blood mononuclear cells (PBMCs) are considered the primary innate immune cells. Objectives: PBMCs derived from goats were infected with PPRV and analyzed to detect the relationship between PPRV replication and apoptosis or the inflammatory response. Methods: Quantitative real-time polymerase chain reaction was used to identify PPRV replication and cytokines expression. Flow cytometry was conducted to detect apoptosis and the differentiation of CD4+ and CD8+ T cells after PPRV infection. Results: PPRV stimulated the differentiation of CD4+ and CD8+ T cells. In addition, PPRV induced apoptosis in goat PBMCs. Furthermore, apoptosis and the inflammatory response induced by PPRV could be suppressed by Z-VAD-FMK and Z-YVAD-FMK, respectively. Moreover, the virus titer of PPRV was attenuated by inhibiting caspase-1-dependent apoptosis and inflammation. Conclusions: This study showed that apoptosis and the inflammatory response play an essential role in PPR viral replication in vitro, providing a new mechanism related to the cell host response.

Characterization and Expression Profile Analysis of a New cDNAEncoding Taxadiene Synthase from Taxus media

Lingxia Zhao,Binhui Guo,Xiaofen Sun,Guoyin Kai,Lei Zhang,Zhugang Li,Dongli Zhao,Zhiqi Miao,Kexuan Tang 한국생화학분자생물학회 2005 BMB Reports Vol.38 No.6

Selection and identification of single-domain antibody against Peste des Petits Ruminants virus

Dan Liu,Lingxia Li,Xiaoan Cao,Jinyan Wu,Guoyu Du,Youjun Shang 대한수의학회 2021 Journal of Veterinary Science Vol.22 No.4

Background: Peste des petits ruminants (PPR) is an infectious disease caused by the peste des petits ruminants virus (PPRV) that mainly produces respiratory symptoms in affected animals, resulting in great losses in the world's agriculture industry every year. Single-domain variable heavy chain (VHH) antibody fragments, also referred to as nanobodies, have high expression yields and other advantages including ease of purification and high solubility. Objectives: The purpose of this study is to obtain a single-domain antibody with good reactivity and high specificity against PPRV. Methods: A VHH cDNA library was established by immunizing camels with PPRV vaccine, and the capacity and diversity of the library were examined. Four PPRV VHHs were selected, and the biological activity and antigen-binding capacity of the four VHHs were identified by western blot, indirect immunofluorescence, and enzyme-linked immunosorbent assay (ELISA) analyses. ELISA was used to identify whether the four VHHs were specific for PPRV, and VHH neutralization tests were carried out. ELISA and western blot analyses were used to identify which PPRV protein was targeted by VHH2. Results: The PPRV cDNA library was constructed successfully. The library capacity was greater than 2.0 × 106 cfu/mL, and the inserted fragment size was approximately 400 bp to 2000 bp. The average length of the cDNA library fragment was about 1000 bp, and the recombination rate was approximately 100%. Four single-domain antibody sequences were selected, and proteins expressed in the supernatant were obtained. The four VHHs were shown to have biological activity, close affinity to PPRV, and no cross-reaction with common sheep diseases. All four VHHs had neutralization activity, and VHH2 was specific to the PPRV M protein. Conclusions: The results of this preliminary research of PPRV VHHs showed that four screened VHH antibodies could be useful in future applications. This study provided new materials for inclusion in PPRV research.

Characterization and Expression Profile Analysis of a New cDNA Encoding Taxadiene Synthase from Taxus media

Kai, Guoyin,Zhao, Lingxia,Zhang, Lei,Li, Zhugang,Guo, Binhui,Zhao, Dongli,Sun, Xiaofen,Miao, Zhiqi,Tang, Kexuan Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.6

A full-length cDNA encoding taxadiene synthase (designated as TmTXS), which catalyzes the first committed step in the Taxol biosynthetic pathway, was isolated from young leaves of Taxus media by rapid amplification of cDNA ends (RACE). The full-length cDNA of TmTXS had a 2586 bp open reading frame (ORF) encoding a protein of 862 amino acid residues. The deduced protein had isoelectric point (pI) of 5.32 and a calculated molecular weight of about 98 kDa, similar to previously cloned diterpene cyclases from other Taxus species such as T. brevifolia and T. chinenisis. Sequence comparison analysis showed that TmTXS had high similarity with other members of terpene synthase family of plant origin. Tissue expression pattern analysis revealed that TmTXS expressed strongly in leaves, weak in stems and no expression could be detected in fruits. This is the first report on the mRNA expression profile of genes encoding key enzymes involved in Taxol biosynthetic pathway in different tissues of Taxus plants. Phylogenetic tree analysis showed that TmTXS had closest relationship with taxadiene synthase from T. baccata followed by those from T. chinenisis and T. brevifolia. Expression profiles revealed by RT-PCR under different chemical elicitor treatments such as methyl jasmonate (MJ), silver nitrate (SN) and ammonium ceric sulphate (ACS) were also compared for the first time, and the results revealed that expression of TmTXS was all induced by the tested three treatments and the induction effect by MJ was the strongest, implying that TmTXS was high elicitor responsive.

Association between Initial Chest CT or Clinical Features and Clinical Course in Patients with Coronavirus Disease 2019 Pneumonia

Liu Zhe,Jin Chao,Wu Carol C.,Liang Ting,Zhao Huifang,Wang Yan,Wang Zekun,Li Fen,Zhou Jie,Cai Shubo,Zeng Lingxia,Yang Jian 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.6

Objective: To identify the initial chest computed tomography (CT) findings and clinical characteristics associated with the course of coronavirus disease 2019 (COVID-19) pneumonia. Materials and Methods: Baseline CT scans and clinical and laboratory data of 72 patients admitted with COVID-19 pneumonia (39 men, 46.2 ± 15.9 years) were retrospectively analyzed. Baseline CT findings including lobar distribution, presence of ground glass opacities, consolidation, linear opacities, and lung severity score were evaluated. The outcome event was recovery with hospital discharge. The time from symptom onset to discharge or the end of follow-up (for those remained hospitalized) was recorded. Data were censored in events such as death or discharge without recovery. Multivariable Cox proportional hazard regression was used to explore the association between initial CT, clinical or laboratory findings, and discharge with recovery, whereby hazard ratio (HR) values < 1 indicated a lower rate of discharge at four weeks and longer time until discharge. Results: Thirty-two patients recovered and were discharged during the study period with a median length of admission of 16 days (range, 9 to 25 days), while the rest remained hospitalized at the end of this study (median, 17.5 days; range, 4 to 27 days). None died during the study period. After controlling for age, onset time, lesion characteristics, number of lung lobes affected, and bilateral involvement, the lung severity score on baseline CT (> 4 vs. ≤ 4 [reference]: adjusted HR = 0.41 [95% confidence interval, CI = 0.18–0.92], p = 0.031) and initial lymphocyte count (reduced vs. normal or elevated [reference]: adjusted HR = 0.14 [95% CI = 0.03–0.60], p = 0.008) were two significant independent factors that influenced recovery and discharge. Conclusion: Lung severity score > 4 and reduced lymphocyte count at initial evaluation were independently associated with a significantly lower rate of recovery and discharge and extended hospitalization in patients admitted for COVID-19 pneumonia.