Abstract Progress in prostate cancer research is presently limited by a shortage of reliable in vitro model systems. The authors describe a novel self‐assembling peptide, bQ13, which forms nanofibers and gels useful for the 3D culture of prostate cancer spheroids, with improved cytocompatibility compared to related fibrillizing peptides. The mechanical properties of bQ13 gels can be controlled by adjusting peptide concentration, with storage moduli ranging between 1 and 10 kPa. bQ13's ability to remain soluble at mildly basic pH considerably improved the viability of encapsulated cells compared to other self‐assembling nanofiber‐forming peptides. LNCaP cells formed spheroids in bQ13 gels with similar morphologies and sizes to those formed in Matrigel or RADA16‐I. Moreover, prostate‐specific antigen (PSA) is produced by LNCaP cells in all matrices, and PSA production is more responsive to enzalutamide treatment in bQ13 gels than in other fibrillized peptide gels. bQ13 represents an attractive platform for further tailoring within 3D cell culture systems.
Abstract Widespread vaccination is essential to global health. Significant barriers exist to improving vaccine coverage in lower‐ and middle‐income countries, including the costly requirements for cold‐chain distribution and trained medical personnel to administer the vaccines. A heat‐stable and highly porous tablet vaccine that can be administered sublingually via simple dissolution under the tongue is described. SIMPL tablet vaccines (Supramolecular IMmunization with Peptides subLingually) are produced by freeze‐drying a mixture of self‐assembling peptide‐polymer nanofibers, sugars, and adjuvant. Sublingual immunization with SIMPL tablets raises antibody responses against both a model epitope from ovalbumin and a clinically relevant epitope from Mycobacterium tuberculosis . Further, sublingual antibody responses are not diminished after heating the tablets for 1 week at 45 °C, in contrast to a more conventional carrier vaccine (KLH). This approach directly addresses the need for a heat‐stable and easily deliverable vaccine to improve equity in global vaccine coverage.
DOCSPER—A Synthetic Lipid Fit for In Vivo ApplicationDOCSPER [1,3-Dioleoyloxy-2-(N5-carbamoyl-spermine)-propane] is a cationic amphiphile consisting of a hydrophobic 1,3 dioleylglycerol moiety and threefold positively charged spermine head group (). We optimised the 5-step-synthesis of the lipospermine and after up-scaling we have obtained sufficient amounts to initiate preclinical investigations. DOCSPER was tested for its ability to transfect eukaryotic cells in vitro. It has proven to possess high transfection efficiency in comparison to commercially available liposomal transfection agents. Furthermore, DOCSPER was extensively tested in several in vivo studies (). These studies revealed a high transfection efficiency, whereas very low toxicity levels were detected. Thus, the results clearly indicate that the cationic lipid DOCSPER is a reliable, low-risk system for broad applications in gene therapy.Groth D. et al. Int J Pharm 1998; 162:143–157.Nikol S. et al. Int J Angiol 2000; 9:87–95.Armeanu S. et al. Mol Ther 2000; 1(4):366–375.
Epitope content plays a critical role in determining T‐cell and antibody responses to vaccines, biomaterials, and protein therapeutics, but its effects are nonlinear and difficult to isolate. Here, molecular self‐assembly is used to build a vaccine with precise control over epitope content, in order to finely tune the magnitude and phenotype of T helper and antibody responses. Self‐adjuvanting peptide nanofibers are formed by co‐assembling a high‐affinity universal CD4+ T‐cell epitope (PADRE) and a B‐cell epitope from Staphylococcus aureus at specifiable concentrations. Increasing the PADRE concentration from micromolar to millimolar elicited bell‐shaped dose‐responses that are unique to different T‐cell populations. Notably, the epitope ratios that maximize T follicular helper and antibody responses differed by an order of magnitude from those that maximized Th1 or Th2 responses. Thus, modular materials assembly provides a means of controlling epitope content and efficiently skewing the adaptive immune response in the absence of exogenous adjuvant; this approach may contribute to the development of improved vaccines and immunotherapies.
