GNUV201, a novel human/mouse cross-reactive and low pH-selective anti-PD-1 monoclonal antibody for cancer immunotherapy.

BACKGROUND: Several PD-1 antibodies approved as anti-cancer therapies work by blocking the interaction of PD-1 with its ligand PD-L1, thus restoring anti-cancer T cell activities. These PD-1 antibodies lack inter-species cross-reactivity, necessitating surrogate antibodies for preclinical studies, which may limit the predictability and translatability of the studies. RESULTS: To overcome this limitation, we have developed an inter-species cross-reactive PD-1 antibody, GNUV201, by utilizing an enhanced diversity mouse platform (SHINE MOUSE™). GNUV201 equally binds to human PD-1 and mouse PD-1, equally inhibits the binding of human PD-1/PD-L1 and mouse PD-1/PD-L1, and effectively suppresses tumor growth in syngeneic mouse models. The epitope of GNUV201 mapped to the "FG loop" of hPD-1, distinct from those of Keytruda® ("C'D loop") and Opdivo® (N-term). Notably, the structural feature where the protruding epitope loop fits into GNUV201's binding pocket supports the enhanced binding affinity due to slower dissociation (8.7 times slower than Keytruda®). Furthermore, GNUV201 shows a stronger binding affinity at pH 6.0 (5.6 times strong than at pH 7.4), which mimics the hypoxic and acidic tumor microenvironment (TME). This phenomenon is not observed with marketed antibodies (Keytruda®, Opdivo®), implying that GNUV201 achieves more selective binding to and better occupancy on PD-1 in the TME. CONCLUSIONS: In summary, GNUV201 exhibited enhanced affinity for PD-1 with slow dissociation and preferential binding in TME-mimicking low pH. Human/monkey/mouse inter-species cross-reactivity of GNUV201 could enable more predictable and translatable efficacy and toxicity preclinical studies. These results suggest that GNUV201 could be an ideal antibody candidate for anti-cancer drug development.

Neuroprotective effect of polysaccharide separated from Perilla frutescens Britton var. acuta Kudo against H2O2-induced oxidative stress in HT22 hippocampus cells.

This study was carried out to evaluate the neuroprotective activity of polysaccharide extracts isolated from Perilla frutescens (PEPF) in H2O2-treated HT22 hippocampus cells. The PEPF treatment was found to increase the anti-oxidant activities of HT22 hippocampus cells. PEPF treatment resulted in a significant protection of HT22 hippocampus cells against H2O2-induced neurotoxicity, this protection ultimately occurred through an inhibition of ROS-mediated intracellular Ca2+ levels leading to MAPKs and NF-κB, as well as the accumulation of PI3K/AKT and Nrf2-mediated HO-1/NQO1 pathways. Furthermore, PEPF not only decreased the expression of Bax, cytochrome c, and cleaved caspases-3, -8, and -9, but also increased the expression of PARP and Bcl-2 in the H2O2-treated HT22 hippocampus cells, which overall contributed to the neuroprotective action. PEPF retains its mitochondrial membrane potential and reduces the elevated levels of sub-G1 phase and apoptotic morphological features induced by H2O2. It also reduces the malondialdehyde levels and enhances the intracellular SOD activity.

Pelvic artery embolization in the management of pelvic arterial bleeding following midurethral sling surgery for stress urinary incontinence.

The transobturator tape (TOT) method is the recent minimally invasive midurethral sling surgery. The TOT method was invented to reduce complication rate of surgical technique for female stress urinary incontinence. Pelvic bleeding following TOT procedure, although extremely rare, could be occurred. We presented three cases which treat pelvic arterial bleeding after midurethral sling (TOT and tension-free vaginal tape Secur) surgery via pelvic artery embolization. Therefore we report our cases with brief review of the literature.

Awareness and experience of menopausal symptom and hormone therapy in korean postmenopausal women.

OBJECTIVES: To investigate awareness and experience of menopausal symptom and hormone therapy in Korean postmenopausal women. METHODS: A total of 570 postmenopausal women were accepted our survey. The women filled out the questionnaires composed of medical and surgical history, menopausal age and symptom, demand of treatment on menopausal symptom, and personal method for overcoming the symptom. Also, we make inquiries about experience of hormone therapy, concern about hormone therapy, improvement of menopausal symptom after therapy, adverse effect, and cause of cease the therapy. RESULTS: According to the survey, 80% (456/570) of the women experienced menopausal symptom. When they felt the symptom at first, 47% (213/570) of women was 46-50 years old. The most common menopausal symptom was hot flushes (141/570). A number of Korean women regarded that menopause was a natural process of ageing (69%). Eighty two % of women thought to need to have treatment on menopausal symptom. However, only half (43%) visited doctor. The most concerned disease after menopause they had answered was osteoporosis (60%) but only 22% of women were taken regular check-up of bone mineral density. The common causes were unwilling to do treatment were concern about adverse effect (51%) and indefinite fear of cancer (32%). Moreover, many women got diverse information about menopause from the mass media than professional advice. CONCLUSION: Only a minority of Korean postmenopausal women with menopausal symptoms had taken a hormone therapy. We should provide appropriate education and counsel to Korean peri-menopause women.

Gene cloning and characterization of MdeA, a novel multidrug efflux pump in Streptococcus mutans.

Multidrug resistance, especially multidrug efflux mechanisms that extrude structurally unrelated cytotoxic compounds from the cell by multidrug transporters, is a serious problem and one of the main reasons for the failure of therapeutic treatment of infections by pathogenic microorganisms as well as of cancer cells. Streptococcus mutans is considered one of the primary causative agents of dental caries and periodontal disease, which comprise the most common oral diseases. A fragment of chromosomal DNA from S. mutans KCTC3065 was cloned using Escherichia coli KAM32 as host cells lacking major multidrug efflux pumps. Although E. coli KAM32 cells were very sensitive to many antimicrobial agents, the transformed cells harboring a recombinant plasmid became resistant to several structurally unrelated antimicrobial agents such as tetracycline, kanamycin, rhodamin 6G, ampicillin, acriflavine, ethidium bromide, and tetraphenylphosphonium chloride. This suggested that the cloned DNA fragment carries a gene encoding a multidrug efflux pump. Among 49 of the multidrug-resistant transformants, we report the functional gene cloning and characterization of the function of one multidrug efflux pump, namely MdeA from S. mutans, which was expressed in E. coli KAM32. Judging from the structural and biochemical properties, we concluded that MdeA is the first cloned and characterized multidrug efflux pump using the proton motive force as the energy for efflux drugs.