A5G27

Cell migration is a method that plays an important role in wound healing, cell differentiation, embryonic development, etc.

The formalin-induced paw inflammation/nociceptive test is a chemical persistent pain model in rodents in which subcutaneous injection of formalin into the hind paw produces spontaneous nocifensive behaviors such as flinching and licking. The response is classically biphasic, consisting of an early acute phase (Phase I) reflecting direct activation of peripheral nociceptors (particularly C-fiber afferents), followed by a later prolonged phase (Phase II) associated with central sensitization in the spinal dorsal horn driven by sustained afferent input and inflammatory signaling. This model is widely used to evaluate analgesic and anti-inflammatory interventions because it captures both peripheral nociception and central sensitization processes within a single assay system.

Subcutaneous cell-line-derived xenograft (CDX) models are established by implanting cultured human cancer cell lines into immunodeficient mice, where the injected cells form localized tumors that can be monitored in vivo as a measure of tumorigenic potential, growth kinetics, and treatment response. These models are widely used in oncology research because they allow reproducible tumor formation and enable comparative assessment of tumor growth between different cell lines or genetic manipulations in a controlled in vivo microenvironment. Subcutaneous implantation of cancer cells in immunodeficient mice is a standard approach for evaluating tumor growth behavior and therapeutic response across multiple cancer types, including prostate, esophageal, pancreatic, and colon cancer models.

The Cell-Exclusion Zone (CEZ) migration assay is an in vitro 2D cell migration method in which a defined cell-free area is created using removable physical barriers such as silicone stoppers, allowing cells to be seeded around the barrier and subsequently migrate into the cleared zone after barrier removal. This approach enables quantification of collective cell migration by monitoring repopulation of the initially cell-free region over time using microscopy-based imaging. Compared with scratch-based wound healing assays, barrier-based exclusion methods are designed to avoid mechanical damage to the extracellular matrix and reduce injury-induced effects on boundary cells, thereby improving interpretability of migration behavior in vitro. The assay readout is typically the progressive reduction in the cell-free area or the number of cells invading the exclusion zone, reflecting coordinated cell motility relevant to physiological processes such as wound healing, epithelial repair, and ca