Low dose of IL-2 combined with rapamycin restores and maintains the long-term balance of Th17/Treg cells in refractory SLE patients.

BACKGROUND: The development of Systemic lupus erythematosus (SLE) has been associated with the balance of Th17 and Treg cells. IL-2 and rapamycin can influence the populations of both Th17 and Treg cells. However, it is unclear whether low dose of IL-2 and rapamycin can relieve the symptoms of SLE patients and what is the mechanisms. In this study, we aim to analyze the effect of low dose of IL-2 plus rapamycin on the number of Tregs, Th17 cells and the ratio of Th17/Treg cells, as well as to evaluate its therapeutic efficacy in refractory SLE patients. RESULT: Fifty refractory SLE patients and 70 healthy controls were enrolled and followed up for 24 weeks. We found that compared with HC, the refractory SLE patients had a lower number of Tregs, a similar number of Th17 cells, but an increased ratio of Th17/Treg. After the treatment, the number of Tregs of the patients at 12th and 24th week was significantly increased. While the number of Th17 cells was unchanged, the ratio of Th17/Treg was significantly decreased at both 6 weeks and 24 weeks. After 6, 12 and 24 weeks of treatment, the SLEDAI score was significantly reduced. The prednison dosage at 6th,12th and 24th week post treatment was significantly decreased. CONCLUSION: Our results support that the reduction of Tregs and the imbalance of Th17/Treg cells were correlated with the occurrence and development of refractory SLE. Low dose of IL-2 combined with rapamycin was able to restore the number of Tregs and the balance of Th17/Treg cells. As a result, this approach was able to induce immune tolerance and promote disease remission, allowing for the reduction in prednisone dosage. TRIAL REGISTRATION: ChiCTR-IPR-16009451 Registration date: 2016/10/16.

Abundance and diversity of ammonia-oxidizing archaea in response to various habitats in Pearl River Delta of China, a subtropical maritime zone.

Ammonia-oxidizing archaea (AOA) are widely considered key to ammonia oxidation in various environments. However, little work has been conducted to simultaneously investigate the abundance and diversity of AOA as well as correlations between archaeal amoA genotypes and environmental parameters of different ecosystems at one district. To understand the abundance, diversity, and distribution of AOA in Pearl River Delta of China in response to various habitats, the archaeal amoA genes in soil, marine, river, lake, hot spring and wastewater treatment plant (WWTP) samples were investigated using real-time fluorescent quantitative PCR and clone libraries. Our analyses indicated that the diversity of AOA in various habitats was different and could be clustered into five major clades, i.e., estuary sediment, marine water/sediment, soil, hot spring and Cluster 1. Phylogenetic analyses revealed that the structure of AOA communities in similar ecological habitats exhibited strong relation. The canonical correspondence method indicated that the AOA community structure was strongly correlated to temperature, pH, total organic carbon, total nitrogen and dissolved oxygen variables. Assessing AOA amoA gene copy numbers, ranging from 6.84 x 10(6) to 9.45 x 10(7) copies/g in dry soil/sediment, and 6.06 x 10(6) to 2.41 x 10(7) copies/L in water samples, were higher than ammonia-oxidizing bacteria (AOB) by 1-2 orders of magnitude. However, AOA amoA copy numbers were much lower than AOB in WWTP activated sludge samples. Overall, these studies suggested that AOA may be a major contributor to ammonia oxidation in natural habitats but play a minor role in highly aerated activated sludge. The result also showed the ratio of AOA to AOB amoA gene abundance was positively correlated with temperature and less correlated with other environmental parameters. New data from our study provide increasing evidence for the relative abundance and diversity of ammonia-oxidizing archaea in the global nitrogen cycle.