Shamasha Rozalin, Ramanathan Sneha Kollenchery, Oskarsdotter Kristin, Boroojeni Fatemeh Rasti, Zielińska Aleksandra, Naeimipour Sajjad, Lifwergren Philip, Reustle Nina, Roberts Lauren, Starkenberg Annika, Kratz Gunnar, Apelgren Peter, Säljö Karin, Rakar Jonathan, Kölby Lars, Aili Daniel, Junker Johan
Experimental Plastic Surgery, Department of Biomedical and Clinical Sciences, Linköping University Hospital, Linköping, 581 83, Sweden.
Center for Disaster Medicine and Traumatology, Department of Biomedical and Clinical Sciences, Linköping University Hospital, Linköping, 581 83, Sweden.
Adv Healthc Mater. 2025 Aug;14(21):e2501430. doi: 10.1002/adhm.202501430. Epub 2025 Jun 12.
Chronic wounds and severe skin injuries pose significant clinical challenges, as existing treatments like cultured epidermal autografts and tissue engineering strategies fail to regenerate functional dermal tissue effectively. These methods often result in scarring due to poor tissue integration, low cell density, and limited extracellular matrix (ECM) production. Conventional skin tissue engineering relies on time-intensive cell expansion, producing constructs that lack the complexity of native dermal structures. Here, a bioprintable biphasic granular hydrogel bioink (µInk) based on cell-laden porous gelatin microcarriers (PGMs) is presented, enabling fabrication of ultra-high cell density constructs that promote ECM production for dermal regeneration in vitro and in vivo. Primary human dermal fibroblasts are cultured and expanded on PGMs in a bioreactor prior µInk formulation. The cell-laden PGMs are cross-linked via copper-free click chemistry, creating a shear-thinning granular bioink. The µInk is 3D bioprinted into structurally stable constructs with high cell viability. In vivo, the bioprinted constructs supported neovascularization, hydrogel remodeling, and tissue integration over 28 days. Cells maintained their tissue-specific phenotype, proliferated, and produced dermal ECM post-transplantation. The µInk offers a promising approach to generating high cell-density constructs for scar-free wound healing and for advancing complex tissue reconstruction.
慢性伤口和严重皮肤损伤带来了重大的临床挑战，因为现有的治疗方法，如培养的表皮自体移植和组织工程策略，无法有效地再生功能性真皮组织。由于组织整合性差、细胞密度低和细胞外基质（ECM）产生有限，这些方法常常导致瘢痕形成。传统的皮肤组织工程依赖于耗时的细胞扩增，所产生的构建体缺乏天然真皮结构的复杂性。在此，我们提出了一种基于载细胞多孔明胶微载体（PGM）的可生物打印双相颗粒水凝胶生物墨水（µInk），能够制造超高细胞密度的构建体，促进体外和体内真皮再生的ECM产生。在制备µInk之前，将原代人真皮成纤维细胞在生物反应器中的PGM上进行培养和扩增。载细胞的PGM通过无铜点击化学交联，形成一种剪切变稀的颗粒生物墨水。将µInk 3D生物打印成具有高细胞活力的结构稳定的构建体。在体内，生物打印的构建体在28天内支持了新血管形成、水凝胶重塑和组织整合。细胞在移植后保持其组织特异性表型，增殖并产生真皮ECM。µInk为生成用于无瘢痕伤口愈合和推进复杂组织重建的高细胞密度构建体提供了一种有前景的方法。
