Science Glossary
Plain-language and technical definitions for key terms in regenerative medicine and cellular science.
Extracellular Vesicles
Tiny packages released by cells that carry messages to other cells — like biological text messages that tell surrounding tissue how to respond and heal.
Membrane-bound nanoparticles secreted by nearly all cell types, including exosomes (30–150 nm) and microvesicles, that transport proteins, lipids, RNA, and signaling molecules to modulate recipient cell behavior via paracrine and endocrine mechanisms.
Growth Factors
Natural proteins in your body that act as signals telling cells to grow, multiply, or repair themselves. They're part of your body's built-in repair system.
Soluble polypeptide signaling molecules that bind to specific cell-surface receptors and activate intracellular signaling cascades regulating proliferation, differentiation, migration, and survival — including VEGF, EGF, TGF-β, and FGF families.
Cytokines
Small proteins that act like chemical messengers between immune and tissue cells — coordinating the body's response to injury or infection, including when to start and stop inflammation.
A broad category of small immunomodulatory proteins (including interleukins, interferons, and tumor necrosis factors) secreted by immune and stromal cells to regulate inflammation, immune cell activation, and tissue remodeling in paracrine and autocrine fashions.
Cellular Signaling
The way cells 'talk' to each other using chemical and molecular messages. This constant communication is what keeps your body's tissues working together and responding properly to damage or stress.
The ensemble of biochemical pathways by which cells detect, interpret, and respond to internal and external stimuli through receptor-mediated transduction cascades (e.g., MAPK, PI3K/Akt, JAK-STAT), governing gene expression, metabolism, and cell fate decisions.
Regenerative Medicine
A field of science and medicine focused on helping the body repair, replace, or restore damaged tissues and organs using the body's own biology or biologically inspired therapies.
An interdisciplinary biomedical field encompassing cell therapy, tissue engineering, gene editing, and biologic interventions aimed at restoring structural and functional integrity to injured or diseased tissues by harnessing or augmenting endogenous repair mechanisms.
Cell-Free Technology
An approach to regenerative therapy that uses signals and molecules released by cells — rather than the cells themselves — to promote healing. It avoids many of the challenges of live-cell therapies.
Therapeutic strategies utilizing acellular secretome fractions — including conditioned media, extracellular vesicles, and isolated bioactive proteins — to recapitulate the paracrine benefits of cell-based therapies without the logistical, immunogenic, and regulatory complexities of live-cell administration.
Exosomes
A specific type of tiny messenger capsule released by cells, smaller than most extracellular vesicles, that carries important biological instructions between cells.
A subclass of extracellular vesicles (30–150 nm) of endosomal origin, formed through the multivesicular body pathway and released upon fusion with the plasma membrane. They are enriched in specific miRNAs, proteins, and lipids that reflect their cell of origin and mediate targeted intercellular communication.
Tissue Repair
The natural process by which your body heals damaged tissue — whether from an injury, surgery, or disease. Regenerative science studies ways to support and enhance this process.
A multi-phase biological process encompassing hemostasis, inflammation, proliferation (angiogenesis, re-epithelialization, granulation tissue formation), and remodeling, coordinated by growth factors, cytokines, and extracellular matrix interactions to restore tissue architecture and function.
Homeostasis
Your body's ability to keep everything balanced and functioning normally — like a thermostat that constantly adjusts to maintain the right temperature. When homeostasis is disrupted, disease or aging accelerates.
The dynamic process by which biological systems maintain stable internal conditions (e.g., pH, temperature, osmolality, metabolic state) through negative feedback mechanisms involving the endocrine, nervous, and immune systems, ensuring optimal cellular and organ function.