Lactobacillus plantarum surface-displayed influenza antigens (NP-M2) with FliC flagellin stimulate generally protective immune responses against H9N2 influenza subtypes in chickens
VETERINARY MICROBIOLOGY
Authors: Li, Qiong-Yan; Xu, Man-Man; Dong, Hang; Zhao, Jin-Hui; Xing, Jun-Hong; Wang, Guan; Yao, Jia-Yun; Huang, Hai-Bin; Shi, Chun-Wei; Jiang, Yan-Long; Wang, Jian-Zhong; Kang, Yuan-Huan; Ullah, Naveed; Yang, Wen-Tao; Yang, Gui-Lian; Wang, Chun-Feng
Abstract
The H9N2 avian influenza virus (AIV) causes serious economic losses to the poultry industry every year. Vaccines that induce a mucosal immune response may be successful against influenza virus infection because its transmission occurs primarily in the mucosa. To develop novel and potent oral vaccines based on Lactobacillus plantarum (L. plantarum) to control the spread of AIV in poultry industry, in the present study, we constructed and expressed fusions of the influenza antigens NP and M2 with the Salmonella Typhimurium flagellinprotein FliC on the surface of L. plantarum. Oral immunization of chicks was performed, and serum antibodies, mucosal antibodies, and specific cellular immunity were detected. Immunizing chicks with avian influenza virus was evaluated. The results showed high levels of IgG in addition to high levels of secretory immunoglobulin A (sIgA) in chickens orally administered recombinant L. plantarum. In addition, the fusion may significantly increase the levels of NP- and M2-specific T cell-mediated immunity in the case of mucosal administration of NC8-pSIP409pgsA'-NP-M2-FliC. Recombinant NC8-pSIP409-pgsA'-NP-M2-FliC mediated effectively protected chickens against influenza virus and reduced virus titers in the lung. Our study outcomes indicate that the expression of influenza NP-M2 and a mucosal adjuvant (FliC), by L. plantarum could generate a mucosal vaccine candidate for animals in the future to defend against AIVs.
In vitro and in vivo anti-salmonella properties of hydroethanolic extract of Detarium microcarpum Guill. & Perr. (Leguminosae) root bark and LC-MS-based phytochemical analysis
JOURNAL OF ETHNOPHARMACOLOGY
Authors: Mbock, Michel Arnaud; Fouatio, William Feudjou; Kamkumo, Raceline Gounoue; Fokou, Patrick Valere Tsouh; Tsofack, Florence Ngueguim; Lunga, Paul-Keilah; Ngang, Jean Justin Essia; Boyomo, Onana; Nkengfack, Augustin Ephrem; Ndjakou, Bruno Lenta; Sewald, Norbert; Boyom, Fabrice Fekam; Dimo, Theophile
Abstract
Ethnopharmacological relevance: Typhoid fever treatment remains a challenge in endemic countries. Detarium microcarpum is traditionally used to manage typhoid. Aim of the study: The study aims to explore the efficacy of hydroethanolic extract of Detarium microcarpum root bark in rats infected with salmonella. Material and methods: The phytochemical profile of the extract was obtained by UHPLC-MS analysis in an attempt of standardization. The in vitro antimicrobial activity was determined using broth dilution method. Salmonella infection was induced by oral administration of S. thyphimurium to immunosuppressed rats. Infected rats were then treated 2 h later with the extract (75, 150 and 300 mg/kg), distilled water (normal and salmonella control) and ciprofloxacin (8 mg/kg) for control. Body weight was monitored and stools were cultured to determine the number of colony-forming units. At the end of treatment, animals were sacrificed, blood and organs were collected for hematological, biochemical and histopathological analyses. Results: Detarium microcarpum extract as well as the isolated compound (rhinocerotinoic acid) exhibited good antimicrobial activity in vitro with bacteriostatic effects. The plant extract significantly (p < 0.05) inhibited the bacterial development in infected animals with an effective dose (ED50) of 75 mg/kg. In addition, the extract prevented body weight loss, hematological, biochemical and histopathological damages in treated rats. Conclusion: Detarium microcarpum extract possesses antisalmonella properties justifying its traditional use for the typhoid fever management.