Hematopoietic Differentiation of Embryoid Bodies Derived from the Human Embryonic Stem Cell Line SNUhES3 in Co-culture with Human Bone Marrow Stromal Cells

Human embryonic stem (ES) cells can be induced to differentiate into hematopoietic precursor cells via two methods: the formation of embryoid bodies (EBs) and co-culture with mouse bone marrow (BM) stromal cells. In this study, the above two methods have been combined by co-culture of human ES-cell-derived EBs with human BM stromal cells. The efficacy of this method was compared with that using EB formation alone. The undifferentiated human ES cell line SNUhES3 was allowed to form EBs for two days, then EBs were induced to differentiate in the presence of a different serum concentration (EB and EB/high FBS group), or co-cultured with human BM stromal cells (EB/BM co-culture group). Flow cytometry and hematopoietic colony-forming assays were used to assess hematopoietic differentiation in the three groups. While no significant increase of CD34+/CD45- or CD34+/CD38- cells was noted in the three groups on days 3 and 5, the percentage of CD34+/CD45- cells and CD34+/CD38- cells was significantly higher in the EB/BM co-culture group than in the EB and EB/high FBS groups on day 10. The number of colony-forming cells (CFCs) was increased in the EB/BM co-culture group on days 7 and 10, implying a possible role for human BM stromal cells in supporting hematopoietic differentiation from human ES cell-derived EBs. These results demonstrate that co-culture of human ES-cell-derived EBs with human BM stromal cells might lead to more efficient hematopoietic differentiation from human ES cells cultured alone. Further study is warranted to evaluate the underlying mechanism

Herpes Simplex Virus Type 2 Seroprevalence in Korea: Rapid Increase of HSV-2 Seroprevalence in the 30s in the Southern Part

To determine the characteristics of seroprevalence of herpes simplex virus type 2 (HSV-2) infection among Korean people, a cross-sectional study was conducted on three groups in 2004. The three groups consisted of the general public who visited public health centers, commercial sex workers (CSWs), and human immunodeficiency virus (HIV)-infected persons. Among the general public, HSV-2 seroprevalence rates for age under the 20s, in the 20s, 30s, 40s and the above 22.6%, 32.7% and 32.3%, respectively, which showed rapid increase of the rate in the 30s (p<0.0001). In case of the above of 19 yr old, women (28.0%) was higher than men (21.7%) (p<0.0001). The rate of CSWs (81.6%) was about 10 times higher than that of general women. In case of HIV-infected men (47.6%), the figure was about 2-3 times higher than that of general men. The low rate in the teens and the 20s proved that it is essential to develop sexually transmitted infections (STIs) prevention programs of education and publicity for them as a precaution measure. This study is the first major study of its kind on HSV-2 and would provide basic data for prevention of STIs including information about target groups subject to vaccination program

Cross-protection against Vibrio cholerae infection by monoclonal antibodies against Vibrio vulnificus RtxA1/MARTX(Vv)

Gram-negative Vibrio species secrete multifunctional autoprocessing repeats-in-toxin (MARTX) toxins associated with bacterial pathogenesis. Here, the cross-reactivity and cross-protectivity of mAbs against V. vulnificus RtxA1/MARTXVv was evaluated. Passive administration of any of these mAbs (21RA, 24RA, 46RA, 47RA and 50RA) provided strong protection against lethal V. cholerae infection. Interestingly, 24RA and 46RA, which map to the cysteine protease domain of V. cholerae MARTXVc, inhibited CPD autocleavage in vitro; this process is involved in V. cholerae pathogenesis. These results generate new insight into the development of broadly protective mAbs and/or vaccines against Vibrio species with MARTX toxins. © 2016 The Societies and John Wiley &amp; Sons Australia, Ltd