Weissella koreensis and Pediococcus pentosaceus bacterial ghosts induce inflammatory responses as immunostimulants.

In this study, bacterial ghosts (BGs) were generated from Weissella koreensis LKS42 (WKorGs) and Pediococcus pentosacues KA94 (PPGs) by chemically inducing lysis using substances such as hydrochloric acid (HCl), sulfuric acid (H2SO4), nitric acid (HNO3), acetic acid (CH3COOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), sodium carbonate (Na2CO3), n-butanol, and C6H8O7. HCl-induced WKorGs and PPGs exhibited complete removal of DNA and displayed transverse membrane dissolution tunnel structures under scanning electron microscopy (SEM). Cell viability assays showed high viability of RAW 264.7 cells exposed to HCl-induced WKorGs and PPGs. Additionally, treatment with HCl-induced WKorGs and PPGs elevated mRNA levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, iNOS) and the anti-inflammatory cytokine IL-10 in RAW 264.7 cells. These findings suggest that HCl-induced WKorGs and PPGs have the potential to be used as inactivated bacterial immunostimulants, highlighting their promising applications in immunization and immunotherapy.

Hydrochloric acid-treated Bacillus subtilis ghosts induce IL-1 beta, IL-6, and TNF-alpha in murine macrophage.

Background: Bacterial ghosts (BGs) are empty cell envelopes commonly generated using Gram-negative bacteria; they represent a potential platform for efficient adjuvant and vaccine delivery systems. However, the efficient production of BGs from bacteria in a short period of time is challenging. Objective: The purpose of this study was to investigate the possibility of producing BGs in the Gram-positive Bacillus subtilis using various chemicals, and the potential application of BGs as a novel immunomodulatory agent. Results: In this study, Bacillus subtilis ghosts (BSGs) were generated, for the first time to the best of our knowledge, using the minimum inhibitory concentration (MIC) of hydrochloric acid (HCl; 6.25 mg/mL), sulfuric acid (H2SO4; 3.125 mg/mL), and nitric acid (HNO3; 6.25 mg/mL). Among the BSGs generated using these chemicals, HCl-induced BSGs were completely DNA-free as confirmed by real-time polymerase chain reaction. Scanning electron microscopy showed the formation of transmembrane lysis tunnel structures in HCl-induced BSGs. Murine macrophages exposed to the HCl-induced BSGs at a concentration of 1 × 105 CFU/mL showed a cell viability of 97.8%. Additionally, HCl-induced BSGs upregulated the expression of pro-inflammatory cytokines including interleukin (IL)-1ß, tumor necrosis factor alpha, and IL-6. Furthermore, we found differences in the protein expression profiles between intact live bacteria and BSGs using two-dimensional electrophoresis coupled with peptide mass fingerprinting/matrix-assisted laser desorption/ionization-time of flight mass spectrometry analysis. Conclusion: These data suggest that the HCl-induced BSGs may be potentially safe and effective candidates for inactivated bacterial vaccines and/or immunostimulants. Supplementary Information: The online version contains supplementary material available at 10.1007/s13273-022-00221-5.

DNA Barcoding of the Korean Lymantria Hübner, 1819 (Lepidoptera: Erebidae: Lymantriinae) for Quarantine Inspection.

DNA barcoding and morphological analyses of Korean Lymantria (Erebidae, Lepidoptera) were conducted for quarantine inspection. In DNA barcoding, Lymantria dispar identified through quarantine inspection was distinguished as three species, L. dispar asiatica, L. albescens, and L. xylina. Lymantria monacha, which is known as a single species in Korea, is revealed as containing three species, L. monacha, L. minomonis, and L. sugii. At the subspecies level, L. dispar dispar formed a single cluster, whereas L. d. asiatica and L. d. japonica formed a cluster containing both subspecies. In morphological re-examination on DNA barcoding results, L. dispar was distinguished from L. albescens by wing pattern, and from L. xylina by papillae anale. L. monacha and the related species were hard to be distinct from each other by using wing pattern, but it was easily distinct through comparison of genitalia. Therefore, DNA barcoding led to accurate identification in species level, but in subspecies level, only a taxon showing geographically far distance was discriminated from the others. These results may provide a taxonomic outline of the Korean Lymantria fauna and may be used as an identification reference for Lymantria species during quarantine inspection.

Downregulation of immune response by the human cytokines Interleukin-32alpha and beta in cell-mediated rejection.

Xenotransplantation of porcine organs has the potential to help overcome the severe shortage of human tissues and organs available for human transplantation. However, numerous hurdles such as immune-mediated xenograft rejection remain before clinical xenotransplantation. In this study, we elucidated the role of human TNF-alpha-inducing factor, Interleukin-32 (IL-32), in porcine kidney cells (PK-15) during cell-mediated rejection by examining host cell responses. CD8+ and CD4+ T cells numbers were reduced in the lymph nodes of PK-15/IL-32beta injected mice. CD3+ Tcells were in mice injected with control cells but PK-15/IL-32alpha- and PK-15/IL-32beta-injected cell numbers were lower in lymph nodes than un transfected controls. In Mixed lymphocyte reaction cultures, the rates of cell proliferation were increased in both PK-15/IL-32alpha- and PK-15/IL-32beta-injected groups compared to the untransfected control groups. The Stable porcine PK-15 cells expression IL-32alpha and IL-32beta inhibited cytotoxic T lymphocyte (CTLs) after cellular xenograft. Our results suggest that human IL-32alpha and IL-32beta regulates on xenograft rejection in cellular xenotransplantation.