skip to main content


Title: Thermophobic Trehalose Glycopolymers as Smart C‐Type Lectin Receptor Vaccine Adjuvants
Abstract

Herein, this work reports the first synthetic vaccine adjuvants that attenuate potency in response to small, 1–2 °C changes in temperature about their lower critical solution temperature (LCST). Adjuvant additives significantly increase vaccine efficacy. However, adjuvants also cause inflammatory side effects, such as pyrexia, which currently limits their use. To address this, a thermophobic vaccine adjuvant engineered to attenuate potency at temperatures correlating to pyrexia is created. Thermophobic adjuvants are synthesized by combining a rationally designed trehalose glycolipid vaccine adjuvant with thermoresponsive poly‐N‐isoporpylacrylamide (NIPAM) via reversible addition fragmentation chain transfer (RAFT) polymerization. The resulting thermophobic adjuvants exhibit LCSTs near 37 °C, and self‐assembled into nanoparticles with temperature‐dependent sizes (90–270 nm). Thermophobic adjuvants activate HEK‐mMINCLE and other innate immune cell lines as well as primary mouse bone marrow derived dendritic cells (BMDCs) and bone marrow derived macrophages (BMDMs). Inflammatory cytokine production is attenuated under conditions mimicking pyrexia (above the LCST) relative to homeostasis (37 °C) or below the LCST. This thermophobic behavior correlated with decreased adjuvantRgis observed by DLS, as well as glycolipid‐NIPAM shielding interactions are observed by NOESY‐NMR. In vivo, thermophobic adjuvants enhance efficacy of a whole inactivated influenza A/California/04/2009 virus vaccine, by increasing neutralizing antibody titers and CD4+/44+/62L+lung and lymph node central memory T cells, as well as providing better protection from morbidity after viral challenge relative to unadjuvanted control vaccine. Together, these results demonstrate the first adjuvants with potency regulated by temperature. This work envisions that with further investigation, this approach can enhance vaccine efficacy while maintaining safety.

 
more » « less
NSF-PAR ID:
10419294
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Healthcare Materials
Volume:
12
Issue:
19
ISSN:
2192-2640
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Delivering stem/progenitor cells via a degradable synthetic membrane to devitalized allogenic tissue graft surfaces presents a promising allograft‐mediated tissue regeneration strategy. However, balancing degradability and bioactivity of the synthetic membrane with physical characteristics demanded for successful clinical translation is challenging. Here, well‐integrated composites of hydroxyapatite (HA) and amphiphilic poly(lactide‐co‐glycolide)‐b‐poly(ethylene glycol)‐b‐poly(lactide‐co‐glycolide) (PELGA) with tunable degradation rates are designed that stiffen upon hydration and exhibit excellent shape recovery ability at body temperature for efficiently delivering skeletal progenitor cells around bone grafts. Unlike conventional degradable polymers that weaken upon wetting, these amphiphilic composites stiffen upon hydration as a result of enhanced polyethylene glycol (PEG) crystallization. HA‐PELGA composite membranes support the attachment, proliferation, and osteogenesis of rat periosteum‐derived cells in vitro, as well as the facile transfer of confluent cell sheets of green fluorescent protein‐labeled bone marrow stromal cells. With efficient shape memory behaviors around physiological temperature, the composite membranes can be programmed with a permanent tubular configuration, deformed into a flat temporary shape desired for cell seeding/cell sheet transfer, and triggered to wrap around a femoral bone allograft upon 37 °C saline rinse and subsequently stiffen. These properties combined make electrospun HA‐PELGA promising smart synthetic periosteal membranes for augmenting allograft healing.

     
    more » « less
  2. Abstract

    The effects of adjuvants for increasing the immunogenicity of influenza vaccines are well known. However, the effect of adjuvants on increasing the breadth of cross-reactivity is less well understood. In this study we have performed a systematic screen of different toll-like receptor (TLR) agonists, with and without a squalene-in-water emulsion on the immunogenicity of a recombinant trimerized hemagglutinin (HA) vaccine in mice after single-dose administration. Antibody (Ab) cross-reactivity for other variants within and outside the immunizing subtype (homosubtypic and heterosubtypic cross-reactivity, respectively) was assessed using a protein microarray approach. Most adjuvants induced broad IgG profiles, although the response to a combination of CpG, MPLA and AddaVax (termed ‘IVAX-1’) appeared more quickly and reached a greater magnitude than the other formulations tested. Antigen-specific plasma cell labeling experiments show the components of IVAX-1 are synergistic. This adjuvant preferentially stimulates CD4 T cells to produce Th1>Th2 type (IgG2c>IgG1) antibodies and cytokine responses. Moreover, IVAX-1 induces identical homo- and heterosubtypic IgG and IgA cross-reactivity profiles when administered intranasally. Consistent with these observations, a single-cell transcriptomics analysis demonstrated significant increases in expression of IgG1, IgG2b and IgG2c genes of B cells in H5/IVAX-1 immunized mice relative to naïve mice, as well as significant increases in expression of the IFNγ gene of both CD4 and CD8 T cells. These data support the use of adjuvants for enhancing the breath and durability of antibody responses of influenza virus vaccines.

     
    more » « less
  3. Abstract

    Nanocellulose is increasingly considered for applications; however, the fibrillar nature, crystalline phase, and surface reactivity of these high aspect ratio nanomaterials need to be considered for safe biomedical use. Here a comprehensive analysis of the impact of cellulose nanofibrils (CNF) and nanocrystals (CNC) is performed using materials provided by the Nanomaterial Health Implications Research Consortium of the National Institute of Environmental Health Sciences. An intermediary length of nanocrystals is also derived by acid hydrolysis. While all CNFs and CNCs are devoid of cytotoxicity, 210 and 280 nm fluorescein isothiocyanate (FITC)‐labeled CNCs show higher cellular uptake than longer and shorter CNCs or CNFs. Moreover, CNCs in the 200–300 nm length scale are more likely to induce lysosomal damage, NLRP3 inflammasome activation, and IL‐1β production than CNFs. The pro‐inflammatory effects of CNCs are correlated with higher crystallinity index, surface hydroxyl density, and reactive oxygen species generation. In addition, CNFs and CNCs can induce maturation of bone marrow–derived dendritic cells and CNCs (and to a lesser extent CNFs) are found to exert adjuvant effects in ovalbumin (OVA)‐injected mice, particularly for 210 and 280 nm CNCs. All considered, the data demonstrate the importance of length scale, crystallinity, and surface reactivity in shaping the innate immune response to nanocellulose.

     
    more » « less
  4. Abstract

    Gaucher disease (GD), the most prevalent lysosomal disorder, is caused byGBA1gene mutations, leading to deficiency of glucocerebrosidase, and accumulation of glycosphingolipids in cells of the mononuclear phagocyte system. While skeletal diseases are the leading cause of morbidity and reduced quality of life in GD, the pathophysiology of bone involvement is not yet fully understood, partly due to lack of relevant human model systems. In this work, we present the first 3D human model of GD using aspiration-assisted freeform bioprinting, which enables a platform tool with a potential for decoding the cellular basis of the developmental bone abnormalities in GD. In this regard, human bone marrow-derived mesenchymal stem cells (obtained commercially) and peripheral blood mononuclear cells derived from a cohort of GD patients, at different severities, were co-cultured to form spheroids and differentiated into osteoblast and osteoclast lineages, respectively. Co-differentiated spheroids were then 3D bioprinted into rectangular tissue patches as a bone tissue model for GD. The results revealed positive alkaline phosphatase (ALP) and tartrate-resistant ALP activities, with multi-nucleated cells demonstrating the efficacy of the model, corroborating with gene expression studies. There were no significant changes in differentiation to osteogenic cells but pronounced morphological deformities in spheroid formation, more evident in the ‘severe’ cohort, were observed. Overall, the presented GD model has the potential to be adapted to personalized medicine not only for understanding the GD pathophysiology but also for personalized drug screening and development.

     
    more » « less
  5. null (Ed.)
    Human mesenchymal stem or stromal cells (hMSCs) are known for their potential in regenerative medicine due to their differentiation abilities, secretion of trophic factors, and regulation of immune responses in damaged tissues. Due to the limited quantity of hMSCs typically isolated from bone marrow, other tissue sources, such as adipose tissue-derived mesenchymal stem cells (hASCs), are considered a promising alternative. However, differences have been observed for hASCs in the context of metabolic characteristics and response to in vitro culture stress compared to bone marrow derived hMSCs (BM-hMSCs). In particular, the relationship between metabolic homeostasis and stem cell functions, especially the immune phenotype and immunomodulation of hASCs, remains unknown. This study thoroughly assessed the changes in metabolism, redox cycles, and immune phenotype of hASCs during in vitro expansion. In contrast to BM-hMSCs, hASCs did not respond to culture stress significantly during expansion as limited cellular senescence was observed. Notably, hASCs exhibited the increased secretion of pro-inflammatory cytokines and the decreased secretion of anti-inflammatory cytokines after extended culture expansion. The NAD+/NADH redox cycle and other metabolic characteristics associated with aging were relatively stable, indicating that hASC functional decline may be regulated through an alternative mechanism rather than NAD+/Sirtuin aging pathways as observed in BM-hMSCs. Furthermore, transcriptome analysis by mRNA-sequencing revealed the upregulation of genes for pro-inflammatory cytokines/chemokines and the downregulation of genes for anti-inflammatory cytokines for hASCs at high passage. Proteomics analysis indicated key pathways (e.g., tRNA charging, EIF2 signaling, protein ubiquitination pathway) that may be associated with the immune phenotype shift of hASCs. Together, this study advances our understanding of the metabolism and senescence of hASCs and may offer vital insights for the biomanufacturing of hASCs for clinical use. 
    more » « less