Refining adipose-derived stem cell isolation for optimal regenerative therapy

Table 1 Various stromal vascular fraction isolation techniques and their effects on adipose-derived stem cell viability and functionality

Isolation techniques	Key features	ADSC viability	ADSC functionality	Ref.
Enzymatic digestion (collagenase)	Commonly used method; effectively degrades extracellular matrix components	High initial viability; slight decrease in viability over time because of enzymatic exposure	Promotes adipogenesis and angiogenesis; weakens ADSCs’ immunomodulatory properties through enzymatic exposure	Jeyaraman et al[1], 2024; Garroni et al[13], 2024; Ruoss et al[14], 2024
Nonenzymatic mechanical disruption	Utilizes physical methods such as centrifugation and filtration; avoids chemical agents	Generally lower initial viability than that achieved with enzymatic methods; weak effects on long-term cell viability	Maintains multipotency with fewer alterations in the secretome profile; improves preservation of native ADSC functions	Mundluru et al[4], 2024; Goulas et al[11], 2024; Tareen et al[15], 2024
Centrifugation-based methods	Separates SVF on the basis of density; often combined with other techniques for enhanced purity	Moderate to high viability; dependent on centrifugation parameters, such as speed and duration	Retains adipogenic and osteogenic potential; weakens immunomodulatory properties through mechanical stress	Jeyaraman et al[1], 2024; Qin et al[5], 2024; Souza et al[6], 2024
Microfluidic channel–based isolation	Advanced method utilizing microfluidic channels for precise cell sorting; minimal physical and chemical stress	High viability because of minimal manipulation; enhanced precision in the isolation of ADSCs from SVF	Preserves a wide range of cellular functions, such as differentiation potential and cytokine secretion	Liu et al[2], 2024; Carr et al[3], 2024; Li et al[12], 2024
Automated closed systems	Fully automated systems with closed environments to reduce contamination; often used in clinical settings	High viability with reduced contamination risks; consistent and reproducible outcomes	Maintains functional properties, as do traditional methods; improves safety for greater clinical applicability	Soltani et al[8], 2024; Ruoss et al[14], 2024; Mohseni Meybodi et al[16], 2024
Hybrid techniques (enzymatic + mechanical)	Combination of enzymatic and mechanical methods to enhance yield and viability	High viability because of the balance between enzymatic efficiency and mechanical preservation of cell integrity	Enhances functional outcomes - for example, by improving differentiation and paracrine effects; allows for tailored applications	Jeyaraman et al[1], 2024; Qin et al[5], 2024; Garroni et al[13], 2024

This table presents information on various stromal vascular fraction isolation techniques and their effects on adipose-derived stem cell viability and functionality. It summarizes the key features of individual techniques, indicating how they influence adipose-derived stem cells’ initial and long-term viability and functional capacities, such as differentiation potential, cytokine secretion, and immunomodulatory properties. References are provided to support the findings. ADSC: Adipose-derived stem cell; SVF: Stromal vascular fraction.

Table 2 Effects of mesenchymal stem cell source and processing protocols on extracellular vesicle composition and therapeutic efficacy

Variables	Description	Ref.
MSC source	Different tissues (adipose, bone marrow, umbilical cord) produce EVs with different profiles. ADMSCs contain elevated levels of proregenerative factors, such as miRNAs that promote angiogenesis and modulate immune responses	Liu et al[2], 2024; Souza et al[6], 2024
Processing protocols	Culture conditions and EV isolation techniques influence EV content and function. Suspension cultures improve EV yield and functionality. Hypoxic preconditioning enhances EVs with tissue repair and immunomodulatory factors	Jeyaraman et al[1], 2024; Suryawan et al[17], 2021
Therapeutic efficacy	Therapeutic potential of MSC-derived EVs is associated with their specific compositional profiles. ADMSC-derived EVs are particularly effective in promoting wound healing and modulating immune responses because of their distinct miRNA and protein contents	Soltani et al[8], 2024; Symonds et al[18], 2023
Challenges and considerations	Variability in EV composition necessitates careful MSC source selection and standardized processing protocols to optimize therapeutic outcomes. Standardization is essential for producing EVs with consistent therapeutic properties	Liu et al[2], 2024; Carr et al[3], 2024

This table summarizes the effects of different mesenchymal stem cell (MSC) sources and processing techniques on the composition and functionality of extracellular vesicle (EVs). MSCs derived from various tissues, particularly adipose tissue, yield EVs with distinct profiles. These EVs are enriched in proregenerative factors such as specific microRNAs. The methods used for cell culture and EV isolation strongly influence the yield, content, and therapeutic efficacy of EVs. For instance, suspension cultures and hypoxic preconditioning enhance the functionality of EVs. The therapeutic potential of EVs is closely associated with their compositional profiles. Therefore, selecting appropriate MSC sources and standardizing processing protocols are crucial for achieving consistent and optimal therapeutic outcomes. ADMSC: Adipose-derived mesenchymal stem cell; EV: Extracellular vesicle; miRNA: MicroRNA; MSC: Mesenchymal stem cell.

Table 3 Recent advances in adipose-derived stem cell applications: Preconditioning techniques, clinical outcomes, and future directions

Preconditioning techniques	Clinical outcomes	Future directions	Ref.
Pharmacological agent use	Increased regenerative capacity; improved immunomodulation	Exploration of novel agents and standardization of therapeutic dosages	Jeyaraman et al[1], 2024; Liu et al[2], 2024
Hypoxic preconditioning	Enhanced ADSC survival; improved wound healing	Further investigation for optimizing hypoxia duration and conditions	Suryawan et al[17], 2021
Mechanical stimulation	Enhanced tissue regeneration; increased cell viability	Development of standardized protocols for mechanical stimulation	Carr et al[3], 2024; Goulas et al[11], 2024
EV modulation	Modulated macrophage polarization; improved anti-inflammatory effects	Investigation of EV content manipulation to optimize therapeutic effects	Souza et al[6], 2024; Symonds et al[18], 2023
Chemical preconditioning	Improved angiogenic capacity; accelerated tissue repair	Identification of optimal chemical agents and concentrations	Qin et al[5], 2024; Li et al[12], 2024
Cytokine preconditioning	Enhanced immunomodulatory properties; reduced inflammation	Further exploration of cytokine combinations for targeted therapies	Yin and Shen[7], 2024; Yang et al[19], 2024

Recent advances in adipose-derived stem cell preconditioning techniques highlight the efficacy of various methods in enhancing clinical outcomes. These techniques include hypoxic preconditioning, pharmacological agent use, mechanical stimulation, extracellular vesicle modulation, chemical preconditioning, and cytokine preconditioning. This table presents findings from recent studies, underscoring improvements in adipose-derived stem cell survival, tissue regeneration, and immunomodulation. In the future, these techniques must be optimized to maximize therapeutic efficacy. ADSC: Adipose-derived stem cell; EV: Extracellular vesicle.