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The formulation of niosomes is influenced by a number of variables, and these variables may eventually affect the formulation’s outcome. One of the elements that can influence the physico-chemical properties of niosomes is the method used in preparation of the formulation. In this study, we established if various methods of preparation have any impact on the prepared vesicles when loaded with 5-fluorouracil. Thereafter, a real-time cell assay (an in vitro cytotoxicity test) against HCT-116 colon cancer cell lines was done on an optimised batch. 5-fluorouracil loaded niosomes were prepared with either Tween 60 or Span 60 by four different methods - namely thin film hydration (TFH), reverse phase evaporation (RPE), evaporation/sonication (EVP/SON), and the ethanol injection method (EIM). In vitro evaluations were done on the formulations, and these included particle size analysis, entrapment efficiency, scanning electron microscopy (SEM), photomicrography, drug release, polydispersity index, and Fourier transform infrared spectroscopy (FTIR). The effects of the preparation method and type of non-ionic surfactants on encapsulation efficiency, particle size, and in vitro drug release of the niosomes at pH 7.4 were evaluated. An in vitro cytotoxicity test (real time cell assay (RTCA)) against HCT-116 cells was carried out using the optimised formulation. Results showed physically stable formulations. The TFH method produced the smallest particle sizes (187 nm and 482 nm), while the EVP/SON method produced the largest particle sizes (4476 nm and 9111 nm). The Tween-based niosomes prepared by TFH or RPE had higher drug entrapment. The FTIR studies of niosomal formulations showed broad peaks at wavenumbers above 3000 cm−1, indicating strong hydrogen bonds. The RTCA showed 5-fluorouracil-loaded niosomes caused more sustained cell death compared to the pure drug and blank niosomes. The methods of preparation affected the particle size, polydispersity index, entrapment efficiency, and the physical stability of the vesicles. The thin film hydration method was more robust in the entrapped 5-fluorouracil and showed lower particle sizes when compared to all the other methods. RTCA showed sustained cell death in real time.

Hematopoietic stem cell (HSC)-based gene therapy targeting CCR5 represents a promising way to cure human immunodeficiency virus type 1 (HIV-1) infection. Yet the preclinical animal model with transplantation of autologous CCR5-ablated HSCs remains to be optimized. In this study, four Chinese rhesus macaques of simian immunodeficiency virus (SIV) chronic infection were given long-term antiretroviral therapy (ART), during which peripheral CD34+ hematopoietic stem and progenitor cells (HSPCs) were purified and infected with CCR5-specific CRISPR/Cas9 lentivirus (three monkeys) or GFP lentivirus (one monkey). After non-myeloablative conditioning, the CCR5-modified or GFP-labeled HSPCs were autotransplanted to four recipients, and ART was withdrawn following engraftment. All of the recipients survived the process of transplantation. The purified CD34+ HSPCs harbored an undetectable level of integrated SIV DNA. The efficiency of CCR5 disruption in HSPCs ranges from 6.5% to 15.6%. Animals experienced a comparable level of hematopoietic reconstuction and displayed a similar physiological homeostasis Despite the low-level editing of CCR5 in vivo (0.3%–1%), the CCR5-disrupted cells in peripheral CD4+ Effector Memory T cell (TEM) subsets were enriched 2- to 3-fold after cessation of ART. Moreover, two of the three treated monkeys displayed a delayed viral rebound and a moderately recovered immune function 6 months after ART withdrawal. This study highlights the importance of improving the CCR5-editing efficacy and augmenting the virus-specific immunity for effective treatment of HIV-1 infection.

We previously reported that Plasmodium infection promotes antitumor immunity in a murine Lewis lung cancer. In this study, we investigated the effects of Plasmodium infection on the tumor inhibition and antitumor CD8+ T cell responses in a murine triple negative breast cancer (TNBCA) model. The results showed that Plasmodium infection significantly inhibited tumor growth, and increased the survival rate of the tumor-bearing mice. Both effector and memory CD8+ T cells were increased in peripheral blood and tumor-draining lymph node (DLN) in the infected mice. The co-stimulatory (CD40L, GITR and OX-40) and co-inhibitory (PD-1, CTLA-4, TIM-3, LAG3) immune checkpoints were up-regulated on CD8+ T cells in infected mice. Importantly, Py induced remarkable effects on the infiltration of CD8+ T cells in the tumor and granzym B+ CD8+ T cells in tumor-bearing mice while not in tumor-free mice. In summary, the results suggested that the effects of Plasmodium infection on murine 4T1 breast cancer might be related to the induction of CD8+ T cell-mediated antitumor immune responses. This finding may provide a novel strategy for the treatment of triple negative breast cancer.