Enhancing cord blood stem cell-derived NK cell growth and differentiation through hyperosmosis.

BACKGROUND: Natural killer (NK) cells hold great promise in treating diverse hematopoietic and solid tumors. Despite their availability from peripheral blood and cord blood, stem cell-derived NK cells offer an 'off-the-shelf' solution. Hematopoietic stem and progenitor cells (HSPCs) derived from cord blood pose no risk to the newborn or mother and are virtually ideal sources for NK cell differentiation. METHODS: We developed a modified protocol to differentiate HSPCs to NK cells under serum-free conditions using defined factors. The HSPC-derived NK (HSC-NK) cells could be expanded in a K562 feeder cell-dependent manner. Furthermore, using lentivirus transduction, chimeric antigen receptor (CAR)-modified HSPCs could be differentiated into NK cells, leading to the establishment of CAR-NK cells. RESULTS: The efficiency of NK cell differentiation from HSPCs was increased through the simple modulation of osmotic pressure by the addition of sodium chloride or glucose. Furthermore, the hyperosmosis-primed HSC-NK cells exhibited enhanced proliferation capacity and maintained normal functional characteristics, including transcriptome and antitumor efficacy. The optimized protocol yielded approximately 1.8 million NK cells from a single CD34-positive cell within a 28-day cycle, which signifies more than a ten-fold increase in efficiency relative to the conventional methods. This optimized protocol was also suitable for generating CAR-NK cells with high yields compared to standard conditions. CONCLUSIONS: The results of this study establish high osmotic pressure as a simple yet powerful adjustment that significantly enhances the efficiency and functionality of HSC-NK cells, including CAR-NK cells. This optimized protocol could lead to cost-effective, high-yield NK cell therapies, potentially revolutionizing cancer immunotherapy strategies.

[Effect of Nitrogen on the Phytoremediation of Cd-PAHs Co-contaminated Dumpsite Soil by Alfalfa (Medicago sativa L.) and on the Soil Bacterial Community Structure].

The key point in facing the demand for the disposal of waste storage in rural areas of China is to manage informal landfills. However, limited studies have been conducted to evaluate the phytoremediation efficiency of heavy metal and polycyclic aromatic hydrocarbon (PAHs) co-contaminated dumpsite soil with high ammonia nitrogen content. In this study, we selected the tolerant plant legume alfalfa (Medicago sativa L.) for a pot experiment to investigate the effects of nitrogen (N) (0, 10, and 50 mg·kg-1) on plant growth, the removal of pollutants, and soil bacterial community structure in Cd-PAHs co-contaminated soil, so as to evaluate the role of N in the process of phytoremediation of dumpsite soil. The results showed that the biomass of alfalfa under high co-contamination conditions (Cd:10 mg·kg-1 and PAHs:400 mg·kg-1) increased with N supply and was 6.0 and 6.3 times higher than that of the treatment without N supply, respectively. Furthermore, the lower N level promoted the growth of alfalfa in the low-contamination group (Cd:1 mg·kg-1 and PAHs:100 mg·kg-1), but the difference was not significant, and a high concentration of N significantly inhibited its growth. In addition, the phytoremediation efficiency for Cd in the low-contamination group ranged from 5.58% to 7.49%, and N significantly increased the efficiency in the high co-contamination group from 0.95% to 3.02%. Compared with the removal of phenanthrene, N had a stronger influence on the removal of pyrene. Meanwhile, alfalfa could promote the removal of them in soil, among which the degradation of PAHs by microorganisms was dominant, whereas the contribution of the plant uptake pathway was less than 0.21%. As reflected by distance-based redundancy analysis (db-RDA), PAHs and Cd were the main factors affecting the structure of the microbial community; moreover, N had a greater effect on bacterial community composition in the single Cd-contamination and high co-contamination groups, promoting genera with bioremediation effects as the dominant soil bacterial communities, including Arthrobacter, Microbacterium, and Novosphingobium. This study will provide a theoretical basis for the remediation of dumpsites as well as informal landfills with contaminated soil.

[New index for soil moisture monitoring based on deltaT(s)-albedo spectral information].

Monitoring soil moisture by remote sensing has been an important problem for both agricultural drought monitoring and water resources management. In the present paper, we acquire the land surface temperature difference (deltaT(s)) and broadband albedo using MODIS Terra reflectance and land surface temperature products to construct the deltaT(s)-albedo spectral feature space. According to the soil moisture variation in spectral feature space, we put forward a simple and practical temperature difference albedo drought index (TDADI) and validate it using ground-measured 0-10 cm averaged soil moisture of Ningxia plain The results show that the coefficient of determination (R2) of both them varies from 0.36 to 0.52, and TDADI has higher accuracy than temperature albedo drought index (TADI) for soil moisture retrieval. The good agreement of TDADI, Albedo/LST, LST/ NDVI and TVDI for analyzing the trends of soil moisture change supports the reliability of TDADI. However, TDADI has been designed only at Ningxia plain and still needs further validation in other regions.