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Despite significant efforts in the study of cardiovascular diseases (CVDs), they persist as the leading cause of mortality worldwide. Considerable research into human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) has highlighted their immense potential in the development of in vitro human cardiac tissues for broad mechanistic, therapeutic, and patient-specific disease modeling studies in the pursuit of CVD research. However, the relatively immature state of hPSC-CMs remains an obstacle in enhancing clinical relevance ofengineered cardiac tissue models. In this study, we describe development of a microfluidic platform for 3D modeling of cardiac tissues, derived from both rat cells and hPSC-CMs, to better recapitulate the native myocardium through co-culture with interstitial cells (specifically cardiac fibroblasts), biomimetic collagen hydrogel encapsulation, and induction of highly anisotropic tissue architecture. The presented platform is precisely engineered through incorporation of surface topography in the form of staggered microposts to enable long-term culture and maturation of cardiac cells, resulting in formation of physiologically relevant cardiac tissues with anisotropy that mimics native myocardium. After two weeks of culture, hPSC-derived cardiac tissues exhibited well-defined sarcomeric striations, highly synchronous contractions, and upregulation of several maturation genes, including HCN1, KCNQ1, CAV1.2, CAV3.1, PLN, and RYR2. These findings demonstrate the ability of the proposed engineered platform to mature animal- as well as human stem cell-derived cardiac tissues over an extended period of culture, providing a novel microfluidic chip with the capability for cardiac disease modeling and therapeutic testing.
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Microbead‐based synthetic niches for in vitro expansion and differentiation of human naïve B‐cells
Abstract As the prospect of engineering primary B‐cells for cellular therapies in cancer, autoimmune diseases, and infectious diseases grows, there is an increasing demand for robust in vitro culture systems that effectively activate human B‐cells isolated from peripheral blood for consistent and efficient expansion and differentiation into various effector phenotypes. Feeder cell‐based systems have shown promise in providing long‐term signaling for expanding B‐cells in vitro. However, these co‐culture systems necessitate more rigorous downstream processing to prevent various feeder cell‐related contaminations in the final product, which limits their clinical potential. In this study, we introduce a microbead‐based CD40L‐presentation platform for stable and consistent activation of human naïve B‐cells. By employing a completely synthetic in vitro culture approach integrating B‐cell receptor, CD21 co‐receptor, toll‐like receptor (TLR‐9), and cytokine signals, we demonstrate that naïve B‐cells can differentiate into memory B‐cells (IgD‐CD38‐/lo + CD27+) and antibody‐secreting cells (IgD‐CD38++CD27+). During this process, B‐cells underwent up to a 50‐fold expansion, accompanied by isotype class switching and low levels of somatic hypermutation, mimicking physiological events within the germinal center. The reproducible generation of highly expanded and differentiated effector B‐cells from naïve B‐cells of multiple donors positions this feeder‐free in vitro synthetic niche as a promising platform for large‐scale production of effector B‐cell therapeutics.
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- Award ID(s):
- 1943020
- PAR ID:
- 10642080
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Bioengineering & Translational Medicine
- Volume:
- 10
- Issue:
- 3
- ISSN:
- 2380-6761
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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