Distribution and pathogen prevalence of field-collected ticks from south-western Korea: a study from 2019 to 2022.

Hard ticks are known vectors of various pathogens, including the severe fever with thrombocytopenia syndrome virus, Rickettsia spp., Coxiella burnetii, Borrelia spp., Anaplasma phagocytophilum, and Ehrlichia spp. This study aims to investigate the distribution and prevalence of tick-borne pathogens in southwestern Korea from 2019 to 2022. A total of 13,280 ticks were collected during the study period, with H. longicornis accounting for 86.1% of the collected ticks. H. flava, I. nipponensis and A. testudinarium comprised 9.4%, 3.6%, and 0.8% of the ticks, respectively. Among 983 pools tested, Rickettsia spp. (216 pools, 1.6% MIR) were the most prevalent pathogens across all tick species, with R. japonica and R. monacensis frequently detected in I. nipponensis and Haemaphysalis spp., respectively. Borrelia spp. (28 pools, 0.2% MIR) were predominantly detected in I. nipponensis (27 pools, 13.8% MIR, P < 0.001). Co-infections, mainly involving Rickettsia monacensis and Borrelia afzelii, were detected in I. nipponensis. Notably, this study identified R. monacensis for the first time in A. testudinarium in South Korea. These findings offer valuable insights into the tick population and associated pathogens in the region, underscoring the importance of tick-borne disease surveillance and prevention measures.

Genomic and phylogenetic analyses of SARS-CoV-2 strains isolated in the city of Gwangju, South Korea

Since the first identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China in late December 2019, the coronavirus disease 2019 (COVID-19) has spread fast around the world. RNA viruses, including SARS-CoV-2, have higher gene mutations than DNA viruses during virus replication. Variations in SARS-CoV-2 genome could contribute to efficiency of viral spread and severity of COVID-19. In this study, we analyzed the locations of genomic mutations to investigate the genetic diversity among isolates of SARS-CoV-2 in Gwangju. We detected non-synonymous and frameshift mutations in various parts of SARS-CoV-2 genome. The phylogenetic analysis for whole genome showed that SARS-CoV-2 genomes in Gwangju isolates are clustered within clade V and G. Our findings not only provide a glimpse into changes of prevalent virus clades in Gwangju, South Korea, but also support genomic surveillance of SARS-CoV-2 to aid in the development of efficient therapeutic antibodies and vaccines against COVID-19.

Direct regulation of IL-2 by curcumin.

Interleukin-2 (IL-2) is a crucial growth factor for both regulatory and effector T cells. Thus, IL-2 plays a critical role in the stimulation and suppression of immune responses. Recently, anti-IL-2 antibodies (Abs) have been shown to possess strong IL-2 modulatory activities by affecting the interaction between IL-2 and IL-2 receptors. In this study, we screened an herbal library to identify a compound that regulates IL-2, which resulted in the identification of curcumin as a direct binder and inhibitor of IL-2. Curcumin is a phytochemical with well-known anti-cancer properties. In this study, curcumin mimicked or altered the binding pattern of anti-IL-2 Abs against IL-2 and remarkably inhibited the interaction of recombinant IL-2 with the IL-2 receptor α, CD25. Interestingly, curcumin neutralized the biological activities of IL-2 both in vitro and in vivo. In this report, we elucidated the unsolved mechanism of the anti-cancer effect of curcumin by identifying IL-2 as a direct molecular target. Curcumin, as a small molecule IL-2 modulator, has the potential to be used to treat IL-2 related pathologic conditions.