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We prove the renormalizability to all orders of a refined Gribov–Zwanziger type action in linear covariant gauges in four-dimensional Euclidean space. In this model, the Gribov copies are taken into account by requiring that the Faddeev–Popov operator is positive definite with respect to the transverse component of the gauge field, a procedure which turns out to be analogous to the restriction to the Gribov region in the Landau gauge. The model studied here can be regarded as the first approximation of a more general nonperturbative BRST invariant formulation of the refined Gribov–Zwanziger action in linear covariant gauges obtained recently in Carpi et al. (2015, 0000). A key ingredient of the set up worked out in Carpi et al. (2015, 0000) is the introduction of a gauge invariant field configuration A μ which can be expressed as an infinite non-local series in the starting gauge field A μ . In the present case, we consider the approximation in which only the first term of the series representing A μ is considered, corresponding to a pure transverse gauge field. The all order renormalizability of the resulting action gives thus a strong evidence of the renormalizability of the aforementioned more general nonperturbative BRST invariant formulation of the Gribov horizon in linear covariant gauges. [ABSTRACT FROM AUTHOR]

The non-perturbative nilpotent exact BRST symmetry of the Gribov–Zwanziger action in the Landau gauge constructed in [1] is generalized to the case of Euclidean Yang–Mills theories quantized in the maximal Abelian gauge. The resulting diagonal gluon propagator is evaluating in dimensions D = 4 , 3 , 2 . In D = 4 , 3 a decoupling type behavior is found in the infrared region, while in D = 2 a scaling type behavior emerges. [ABSTRACT FROM AUTHOR]

The inverse of the Faddeev–Popov operator plays a pivotal role within the Gribov–Zwanziger approach to the quantization of Euclidean Yang–Mills theories in Landau gauge. Following a recent proposal (Capri et al., 2014), we show that the inverse of the Faddeev–Popov operator can be consistently coupled to quark fields. Such a coupling gives rise to a local action while reproducing the behaviour of the quark propagator observed in lattice numerical simulations in the non-perturbative infrared region. By using the algebraic renormalization framework, we prove that the aforementioned local action is multiplicatively renormalizable to all orders. [ABSTRACT FROM AUTHOR]

Recent advances in human mesenchymal stem cell (hMSC)-based clinical therapies for stroke, graft vs. host disease and degenerative diseases has elevated the need for the production of large numbers of functional cells in scalable, homogeneous and cost-effective processes. Current 2D static culture method can not meet the anticipated demand for cells as it is labor intensive, not scalable and not a controlled system. Bioreactor system with microcarriers as a matrix in combination with optimized xeno-free (XF) medium represent a preferred culture structure towards clinical applications. The current xeno-free culture media for hMSC are specially designed for 2D static culture and are not necessarily suitable for 3D environment. The addition of undefined animal components such as serum to the media to enable the culture of hMSC on microcarriers in suspension pose safety concerns and it can be a major obstacle for obtaining regulatory approval when required. The present study evaluated a novel GMP compliant, serum-free (SF), XF hMSC expansion medium, with auxiliary solutions for attachment and dissociation suitable for microcarrier cultures in bioreactors. Results demonstrate the feasibility of expanding hMSC from various sources (one marrow, Wharton Jelly and adipose tissue) in a scalable microcarrier-based culture system using an optimized xeno-free medium while maintaining cell characteristics. Stability studies over 1 year, validated that the media was able to support robust hMSC growth and colony formation. The microcarrier suspension culture system combined with SF media represents a significant footstep for large-scale expansion of regulatory accepted hMSC for cellular therapeutics. [ABSTRACT FROM AUTHOR]

The development of T cell-based immunotherapies like chimeric antigen receptor (CAR) T cells and tumor-infiltrating lymphocytes (TILs) has shown great promise in cancer treatment. However, robust manufacturing of T cell products faces challenges including variability of cellular starting material and the use of human serum-containing media. This study present Nutri-T, a novel Animal Component-Free (ACF) medium, tailored for the expansion of T cells from healthy donors and cancer patients. Nutri-T ACF medium consists of recombinant proteins and other defined pharmaceutical-grade components optimized to promote rapid T cell proliferation. The exclusion of components originating from human and animals ensures ethical procurement and augments patient safety. The medium underwent systematic examination utilizing diverse culture systems, including conventional plastic culture ware, gas-permeable systems (G-Rex), spinners, and small-scale bioreactors. T cells from both healthy donors and cancer patients were expanded in Nutri-T ACF in comparison to other ACF formulations as well as conventional serum-containing media. Results indicate the outstanding performance of Nutri-T ACF medium, demonstrating high fold expansion for both healthy and patient T cells. Importantly, it maintained a naive and cytotoxic T cell phenotype ideal for cell therapy. In terms of functionality, T cells expanded in Nutri-T exhibited potent target cell killing and enabled efficient CAR transduction and expansion of the engineered T cells, all accomplished within a regulatory-friendly environment. In summary, Nutri-T ACF medium exhibits optimal performance specially tailored for T cell manufacture. By enabling a reliable and scalable expansion of T cells, this advanced ACF medium holds the potential to significantly streamline the efficient production of quality-assured T cells for immunotherapy, ultimately enhancing patient outcomes. [ABSTRACT FROM AUTHOR]

Human mesenchymal stem cells (hMSC) play a pivotal role in cell-based therapies, owing to their profound regenerative capabilities. However, the conventional use of planar culture systems for hMSC faces scalability limitations when large quantities are required for clinical applications, partially due to the pre-coating requirement. Additionally, regulatory considerations underscore the need for an ethical and safe culture system devoid of animal-derived components. To address these challenges, a novel Animal Component-Free (ACF) medium was developed, specifically tailored for hMSC cultured on ACF microcarriers (MCs) suspension culture. To develop the ACF culture medium, recombinant proteins known to support hMSC growth and various ACF and pharmacopeial grade components were carefully selected and combined. The concentrations and compatibility with different ACF microcarriers (MCs) suitable for cells culture were tested and optimized. The ACF culture medium and MCs were evaluated using hMSC from various sources in monolayer seed train (2D) and suspension culture systems including spinners, shake flasks and Amber 250 modular bioreactor (Sartorius) without pre-coating. The innovative ACF culture medium exhibited outstanding performance in supporting hMSC expansion in variety of dynamic ACF MC's-based suspension culture systems without pre-coating. Furthermore, the medium demonstrated optimal performance in 2D culture systems. In summary, the study delineates the efficacious formulation of an innovative ACF culture medium tailored for hMSC-based MC's suspension culture towards cell-based therapies. The ACF medium exhibited excellent efficacy in facilitating hMSC expansion, maintaining their multipotent characteristics, and facilitating both three-dimensional growth on microcarriers and 2D culture. Top of FormThe exclusion of components originating from animals ensures ethical procurement and augments patient safety. The scalable cultivation of hMSC utilizing the ACF medium exhibits significant potential for the progression of cell-based therapeutics and regenerative medicine. [ABSTRACT FROM AUTHOR]

hMSC are a critical raw material for cell-based therapies and usually a large number of cells are required for clinical applications. Cryopreservation is currently the only method to preserve cells with maintained functional properties and genetic stability for long term storage. To date, a common practice is use of homebrew cryo-medium that is composed of animal-derived raw materials and low Mw Cryoprotective agents (CPAs), usually 10-20% DMSO. Alternatively, animal component free (ACF) freezing solutions were developed for clinical applications, but they are still based on culture medium and are composed of 10% DMSO (e.g. NutriFreez™ D10). In addition, a few products were developed with a reduced concentration of DMSO or even without DMSO. However, these products appear not to be optimal for hMSC. Moreover, most of the commercially available DMSO-free products are actually composed of other potentially toxic permeable CPAs (e.g. Ethylene Glycol, EG). Exposure of cells to these materials can impact the quality, safety and efficacy of cell-based therapeutic product. Facing strict regulatory requirements, the development of defined, ACF, salt base freezing solution with reduced concentration of DMSO is essential. The current study presents the feasibility of a novel defined, ACF, protein free, salt base freezing solution composed of 5% DMSO for cryopreservation of hMSC from various sources. Results show that the novel cryopreservation solution efficiently maintains high cell yield and viability, and supports the recovery of hMSC while maintaining the normal hMSC features: typical fibroblast-like cell morphology, phenotypic surface marker profile, differentiation capability as well as self-renewal potential. Clinically accepted, cryopreservation solution for hMSC holds a unique opportunity to facilitate the translation of these cells to cellular therapy applications. [ABSTRACT FROM AUTHOR]