Volume 23, Issue 12, Dec. 2024
Volume 23, Issue 10, Oct. 2024
Virus neutralization (VN) antibody is deffned as a critical immune correlate for avian inffuenza vaccines. However, particular types of vaccines induce low levels of VN antibodies but can protect against avian inffuenza viruses, indicating novel mechanisms of protection. In our study, we reported that H7N9 avian inffuenza vaccine based on Newcastle disease virus vector (NDVvecH7N9) elicited low VN antibody titers but high levels of non-neutralizing antibodies against H7N9 virus in chickens. Passive transfer of these antibodies to chickens conferred complete protection from H7N9 virus challenge. The NDVvecH7N9 immune serum can induce strong lysis of H7N9 virus-infected cells and signiffcantly inhibit H7N9 virus infectivity. These activities of the serum were dependent on the engagement of the complement system as well as recognition of the epitope 150-SGS-152 in the hemagglutinin by the antibodies. Our ffndings suggest that activation of the complement system by antibodies elicited by NDVvecH7N9 contributes to protection in chickens. Our study unveils a previously-unidentiffed role of the complement system in protection conferred by NDVvecH7N9 in chickens, providing novel insights into the immune mechanism of H7N9 vaccines. The cover illustration depicts the mechanism of antibody-dependent complement-mediated protection of NDVvecH7N9, which is provided by Prof. Xiufan Liu and Dr. Zenglei Hu from Yangzhou University, China. See pages 2052–2064 for more details.
We initially identified differentially expressed genes (DEGs) by comparing the transcriptomes of folic acid (FA)-treated and water-treated (CK) berries at different time points, and then analyzed the sequences to detect alternatively spliced (AS) genes associated with postharvest softening. During the postharvest storage of FA-treated berries, the VvPE2 gene, which encodes a cell wall-degrading enzyme, undergoes alternative splicing giving rise to two transcripts: the full-length isoform VvPE2.1 and the alternatively spliced form VvPE2.2. VvPE2.1 possesses the complete structure of the PECTINESTERASE gene, and the encoded protein maintains full enzyme functionality, whereas VvPE2.2 encodes an incomplete protein. The up-regulation of VvPE2.2 in FA-treated berries is expected to reduce the accumulation of VvPE2.1, subsequently leading to reduced enzymatic degradation of pectin by PE, thus delaying berry softening. This study provides a comprehensive analysis of AS events in postharvest grape berries using transcriptome sequencing and underscores the pivotal role of VvPE2 during the postharvest storage of grape berries. The cover photo was provided by Dr. Maosong Pei, College of Horticulture and Plant Protection, Henan University of Science and Technology. See pages 863–875 for details.