Enhanced tumor control and survival in preclinical models with adoptive cell therapy preceded by low-dose radiotherapy.

Introduction: Effective infiltration of chimeric antigen receptor T (CAR-T) cells into solid tumors is critical for achieving a robust antitumor response and improving therapeutic outcomes. While CAR-T cell therapies have succeeded in hematologic malignancies, their efficacy in solid tumors remains limited due to poor tumor penetration and an immunosuppressive tumor microenvironment. This study aimed to evaluate the potential of low-dose radiotherapy (LDRT) administered before T-cell therapy to enhance the antitumor effect by promoting CAR-T cell infiltration.

Supramolecular Organization of Collagen Fibrils in Healthy and Osteoarthritic Human Knee and Hip Joint Cartilage.

Cartilage matrix is a composite of discrete, but interacting suprastructures, i.e. cartilage fibers with microfibrillar or network-like aggregates and penetrating extrafibrillar proteoglycan matrix.

Superior Rim Stability of the Lens Capsule Following Manual Over Femtosecond Laser Capsulotomy.

Purpose: Cataract surgery requires the removal of a circular segment of the anterior lens capsule (LC) by manual or femtosecond laser (FL) capsulotomy. Tears in the remaining anterior LC may compromise surgical outcome. We investigated whether biophysical differences in the rim properties of the LC remaining in the patient after manual or FL capsulotomy (FLC) lead to different risks with regard to anterior tear formation.

Nonmulberry Silk Fibroin Scaffold Shows Superior Osteoconductivity Than Mulberry Silk Fibroin in Calvarial Bone Regeneration.

Recent years have witnessed the advancement of silk biomaterials in bone tissue engineering, although clinical application of the same is still in its infancy. In this study, the potential of pure nonmulberry Antheraea mylitta (Am) fibroin scaffold, without preloading with bone precursor cells, to repair calvarial bone defect in a rat model is explored and compared with its mulberry counterpart Bombyx mori (Bm) silk fibroin. After 3 months of implantation, Am scaffold culminates in a completely ossified regeneration with a progressive increase in mineralization at the implanted site.

Material properties of the internal limiting membrane and their significance in chromovitrectomy.

Intraoperative visualization of the internal limiting membrane (ILM), the choice of a point of vantage for lifting an initial flap, the precision with which the ILM is grasped, adhesion between the forceps and the ILM, thickness, stiffness and elasticity of the ILM as well as monitoring of the completeness of ILM removal are all important factors for safety and efficacy of a chromovitrectomy intervention. The understanding of the underlying physical features of the ILM, such as contrast behavior and bioanatomical and biomechanical properties represent, thus, useful prerequisites for successful macular surgery. New analytical tools, such as atomic force microscopy and chromaticity analysis, allow new insights into ILM material characteristics, permitting a systematic approach to refinement of surgical technique.

The role of 3D structure and protein conformation on the innate and adaptive immune responses to silk-based biomaterials.

We have investigated monocyte and T cell responsiveness to silk based biomaterials of different physico-chemical characteristics. Here we report that untransformed CD14+ human monocytes respond to overnight exposure to silk fibroin-based biomaterials in tridimensional form by IL-1β and IL-6, but not IL-10 gene expression and protein production. In contrast, fibroin based materials in bidimensional form are unable to stimulate monocyte responsiveness.

The bi-functional organization of human basement membranes.

The current basement membrane (BM) model proposes a single-layered extracellular matrix (ECM) sheet that is predominantly composed of laminins, collagen IVs and proteoglycans. The present data show that BM proteins and their domains are asymmetrically organized providing human BMs with side-specific properties: A) isolated human BMs roll up in a side-specific pattern, with the epithelial side facing outward and the stromal side inward. The rolling is independent of the curvature of the tissue from which the BMs were isolated.

The nanomechanical signature of breast cancer.

Cancer initiation and progression follow complex molecular and structural changes in the extracellular matrix and cellular architecture of living tissue. However, it remains poorly understood how the transformation from health to malignancy alters the mechanical properties of cells within the tumour microenvironment. Here, we show using an indentation-type atomic force microscope (IT-AFM) that unadulterated human breast biopsies display distinct stiffness profiles.

Oriented lamellar silk fibrous scaffolds to drive cartilage matrix orientation: towards annulus fibrosus tissue engineering.

A novel design of silk-based scaffold is developed using a custom-made winding machine, with fiber alignment resembling the anatomical criss-cross lamellar fibrous orientation features of the annulus fibrosus of the intervertebral disc. Crosslinking of silk fibroin fibers with chondroitin sulphate (CS) was introduced to impart superior biological functionality. The scaffolds, with or without CS, instructed alignment of expanded human chondrocytes and of the deposited extracellular matrix while supporting their chondrogenic redifferentiation.

Nanoscale topographic and biomechanical studies of the human internal limiting membrane.

Purpose: The purpose of this article was to create a nanometer scale topographic and biomechanical profile of the human internal limiting membrane (ILM) under native conditions.

Methods: ILMs from the posterior pole of postmortem human eyes were prepared as flat mounts and investigated by atomic force microscopy (AFM) under physiological conditions. Structural analysis was complemented by transmission electron microscopy.

The nanomechanical properties of rat fibroblasts are modulated by interfering with the vimentin intermediate filament system.

The contribution of the intermediate filament (IF) network to the mechanical response of cells has so far received little attention, possibly because the assembly and regulation of IFs are not as well understood as that of the actin cytoskeleton or of microtubules. The mechanical role of IFs has been mostly inferred from measurements performed on individual filaments or gels in vitro. In this study we employ atomic force microscopy (AFM) to examine the contribution of vimentin IFs to the nanomechanical properties of living cells under native conditions.

Atomic force microscopy for biological imaging and mechanical testing across length scales.

Atomic force microscopy (AFM) offers researchers a unique opportunity to visualize, manipulate, and quantitatively assess structural and mechanical aspects of native biological samples with nanometer resolution. An unparalleled advantage of AFM over other high-resolution microscopes is that biological specimens, ranging from tissues to cells to molecules, can be investigated in physiologically relevant aqueous environments. The AFM can be operated at 37°C, which makes it ideal for in situ cell or tissue studies.

Preparation of microsphere tips for atomic force microscopy (AFM).

This protocol describes the preparation and use of spherical indenters for micrometer-scale imaging and mechanical testing with atomic force microscopy (AFM). A spherical indenter is prepared by gluing a hard borosilicate sphere to a tipless cantilever. For this purpose, a stereomicroscope with a micromanipulator attachment is employed.

Imaging collagen II using atomic force microscopy (AFM).

Collagen II is a fibrous protein that assembles from basic tropocollagen subunits to form extracellular supramolecular fiber networks within cartilage tissue. Tropocollagen subunits of ~300 nm in length self-assemble first into pentameric uniform microfibrils, which fuse into bigger collagen fibrils that can range from 10 nm to 500 nm in diameter. The collagen fibrils display a characteristic 67-nm repeat because of the staggering of individual collagen molecules with respect to each other.

Imaging fibroblast cells using atomic force microscopy (AFM).

Atomic force microscopy (AFM) can be used to visualize the three major cytoskeletal components that contribute to the mechanical properties of the cell. These are actin microfilaments, intermediate filaments, and microtubules. In this protocol, rat embryonic fibroblasts expressing actin tagged with green fluorescent protein (GFP) are used to demonstrate this procedure.

Imaging articular cartilage tissue using atomic force microscopy (AFM).

Cartilage is a complex avascular tissue composed of cells ("chondrocytes") embedded in an extracellular matrix (ECM) consisting of 70%-80% water. The primary components of the ECM are negatively charged aggrecans and collagen II fibrils, which possess a characteristic, ordered three-dimensional structure. The components interact to ensure that the cartilage is able to absorb shock and can function to protect the bone ends.

Micro- and nanomechanical analysis of articular cartilage by indentation-type atomic force microscopy: validation with a gel-microfiber composite.

As documented previously, articular cartilage exhibits a scale-dependent dynamic stiffness when probed by indentation-type atomic force microscopy (IT-AFM). In this study, a micrometer-size spherical tip revealed an unimodal stiffness distribution (which we refer to as microstiffness), whereas probing articular cartilage with a nanometer-size pyramidal tip resulted in a bimodal nanostiffness distribution. We concluded that indentation of the cartilage's soft proteoglycan (PG) gel gave rise to the lower nanostiffness peak, whereas deformation of its collagen fibrils yielded the higher nanostiffness peak.

Anabolic and catabolic responses of human articular chondrocytes to varying oxygen percentages.

Introduction: Oxygen is a critical parameter proposed to modulate the functions of chondrocytes ex-vivo as well as in damaged joints. This article investigates the effect of low (more physiological) oxygen percentage on the biosynthetic and catabolic activity of human articular chondrocytes (HAC) at different phases of in vitro culture.

Methods: HAC expanded in monolayer were cultured in pellets for two weeks (Phase I) or up to an additional two weeks (Phase II).

Stretching, unfolding, and deforming protein filaments adsorbed at solid-liquid interfaces using the tip of an atomic-force microscope.

Cells move by actively remodeling a dense network of protein filaments. Here we analyze the force response of various filaments in a simplified experimental setup, where single filaments are moved with an atomic-force microscope (AFM) tip against surface friction, with the AFM operating in the torsional mode. Our experimental findings are well explained within a simple model based on Newtonian mechanics: we observe force plateaus, which are the signature of the sequential stretching of single repeat units, followed ultimately by deformation of the whole polymer shape.

Status of women in small academic medical communities: case study of the Zagreb University School of Medicine.

Aim: To analyze the proportion of women among student and teaching bodies of the Zagreb University School of Medicine between 1950 and 2000.

Methods: The data on medical school graduates from the Zagreb University School of Medicine between 1950 and 2000 were collected from the archive of the School. The data on the School's teaching staff between 1950 and 2000 were collected from the Archive of the Zagreb University.