Antitumor activity of Z15-0-2, a bispecific nanobody targeting PD-1 and CTLA-4.

The combination of programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte antigen 4 (CTLA-4) antibodies has potential for enhancing clinical efficacy. We described the development and antitumor activity of Z15-0, a bispecific nanobody targeting both the PD-1 and CTLA-4 pathways simultaneously. We designed and optimized the mRNA sequence encoding Z15-0, referred to as Z15-0-2 and through a series of in vitro and in vivo experiments, we established that the optimized Z15-0-2 mRNA sequence significantly increased the expression of the bispecific nanobody. Administration of Z15-0-2 mRNA to tumor-bearing mice led to greater inhibition of tumor growth compared to controls. In aggregate, we introduced a novel bispecific nanobody and have re-engineered it to boost expression of mRNA, representing a new drug development paradigm.

Nitric oxide (NO) involved in Cd tolerance in NHX1 transgenic duckweed during Cd stress.

Anthropogenic activities cause heavy metal pollution, such as cadmium (Cd). Na+/H+ antiporter (NHX1) transgenic duckweed showed Cd tolerance in our previous study, and the signal mechanism needs to be explored. As an important signal molecule, nitric oxide (NO) is involved in a number of functions under abiotic stress response. This study analyzed the levels of endogenous NO in wild-type (WT) duckweed and NHX1 duckweed under Cd treatment. The results showed that after 24 h Cd treatment, the endogenous NO level of WT duckweed decreased, which was significantly lower than that in NHX1 duckweed. Studies have proved that NHX1 influences pH. The level of NO in this study has been investigated at different pH. The NO level was the highest in the duckweed cultured with pH 5.3. Nitrate reductase gene expression was down-regulated and NO synthesis was decreased under Cd stress in WT duckweed. This study showed that NO level has been modified in NHX1 duckweed, which could be influcened by pH.

Declined cadmium accumulation in Na+/H+ antiporter (NHX1) transgenic duckweed under cadmium stress.

Cadmium (Cd) is a serious threat to plants health. Though some genes have been reported to get involved in the regulation of tolerance to Cd, the mechanisms underlying this process are not fully understood. Na+/H+ antiporter (NHX1) plays an important role in Na+/H+ trafficking. The salt and cadmium stress tolerance were found to be enhanced by NHX1 in duckweed according to our previous study, however, its function in Cd2+ flux under Cd stress has not been studied. Here we explored the Cd2+ flux in wild type (WT) and NHX1 transgenic duckweed (NHX1) under Cd stress. We found that the Cd2+ influx in NHX1 duckweed was significantly declined, followed by an increased Cd2+ efflux after 20 min treatment of Cd, which resulted a less accumulation of Cd in NHX1. Reversely, inhibition of NHX1 by amiloride treatment, enhanced Cd2+ influx in NHX1 duckweed, subsequently delayed Cd2+ efflux in both genotypes of duckweed under Cd2+ shock. H+ efflux in NHX1 duckweed was lower compare with that in WT with 20 min Cd2+ shock. NHX1 also increased the pH value with Cd2+ stress in the transgenic rhizoid. These finding suggested a new function of NHX1 in regulation of Cd2+ and H+ flow during short-term Cd2+ shock.