Cichoric acid from extracted Echinacea purpurea induces the proliferation and apoptosis of peripheral blood mononuclear cells from yaks

BACKGROUND: Cichoric acid (CA) is extracted from Echinacea purpurea. It is well known and widely used for its immunological function. However, the effect of CA on peripheral blood mononuclear cells (PBMCs) from yaks is still unclear. This study investigated the potential influences of CA on the proliferation, cytokine induction, and apoptosis of PBMCs from Datong yak in vivo, and aimed to provide a basis for exploring the pharmacological activities of CA on yaks. RESULTS: In this study, CA promoted PBMCs proliferation by combining concanavalin A (Con A) and exhibited a dose-dependent effect as demonstrated by a Cell Counting Kit-8. The concentration of 60 µg/ml CA was the best and promoted the transformation from the G0/G1 phase to the S and G2/M phases with Con A. Furthermore, 60 µg/ml CA significantly increased IL-2, IL-6, and IFN-γ levels and PCNA, CDK4 and Bcl-2 expression levels, but it significantly inhibited the TP53, Bax, and Caspase-3 expression levels. Transcriptome analysis revealed a total of 6807 differentially expressed genes (DEGs) between the CA treatment and control groups. Of these genes, 3788 were significantly upregulated and 3019 were downregulated. Gene Ontology and pathway analysis revealed that DEGs were enriched in cell proliferation and immune function signaling pathways. The expression level of some transcription factors (BTB, Ras, RRM_1, and zf-C2H2) and genes (CCNF, CCND1, and CDK4) related to PBMCs proliferation in yaks were significantly promoted after CA treatment. By contrast, anti-proliferation-associated genes (TP53 and CDKN1A) were inhibited. CONCLUSIONS: In summary, CA could regulate the immune function of yaks by promoting proliferation and inhibiting inflammation and apoptosis of PBMCs.

Antibody Preparations from Human Transchromosomic Cows Exhibit Prophylactic and Therapeutic Efficacy against Venezuelan Equine Encephalitis Virus.

Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne RNA virus that causes low mortality but high morbidity rates in humans. In addition to natural outbreaks, there is the potential for exposure to VEEV via aerosolized virus particles. There are currently no FDA-licensed vaccines or antiviral therapies for VEEV. Passive immunotherapy is an approved method used to protect individuals against several pathogens and toxins. Human polyclonal antibodies (PAbs) are ideal, but this is dependent upon serum from convalescent human donors, which is in limited supply. Non-human-derived PAbs can have serious immunoreactivity complications, and when "humanized," these antibodies may exhibit reduced neutralization efficiency. To address these issues, transchromosomic (Tc) bovines have been created, which can produce potent neutralizing human antibodies in response to hyperimmunization. In these studies, we have immunized these bovines with different VEEV immunogens and evaluated the protective efficacy of purified preparations of the resultant human polyclonal antisera against low- and high-dose VEEV challenges. These studies demonstrate that prophylactic or therapeutic administration of the polyclonal antibody preparations (TcPAbs) can protect mice against lethal subcutaneous or aerosol challenge with VEEV. Furthermore, significant protection against unrelated coinfecting viral pathogens can be conferred by combining individual virus-specific TcPAb preparations.IMPORTANCE With the globalization and spread or potential aerosol release of emerging infectious diseases, it will be critical to develop platforms that are able to produce therapeutics in a short time frame. By using a transchromosomic (Tc) bovine platform, it is theoretically possible to produce antigen-specific highly neutralizing therapeutic polyclonal human antibody (TcPAb) preparations in 6 months or less. In this study, we demonstrate that Tc bovine-derived Venezuelan equine encephalitis virus (VEEV)-specific TcPAbs are highly effective against VEEV infection that mimics not only the natural route of infection but also infection via aerosol exposure. Additionally, we show that combinatorial TcPAb preparations can be used to treat coinfections with divergent pathogens, demonstrating that the Tc bovine platform could be beneficial in areas where multiple infectious diseases occur contemporaneously or in the case of multipathogen release.