Cell Culture & Stem Cells – Fundamental Biomedical Techniques

Vocabulary flashcards covering essential terms and definitions related to cell culture techniques and stem cell biology from the lecture notes.

Cell Culture

The process of growing animal-derived cells outside the organism under controlled laboratory conditions.

Primary Culture

Culture established directly from animal tissue; closely mimics in-vivo physiology and has a finite lifespan.

Secondary Culture

Culture obtained after the first sub-culture of a primary culture.

Cell Line

Population of cells derived from a primary culture after sub-culturing; may be finite or continuous.

Finite Cell Line

Cell line with limited divisions (≈2–100 population doublings) before senescence.

Continuous Cell Line

Laboratory-transformed or tumor-derived line capable of indefinite proliferation in culture.

Cell Strain

Sub-population of a cell line selected (e.g., by cloning); often bears additional genetic changes.

Immortalization

Acquisition of unlimited proliferative capacity by cultured cells, often via genetic transformation.

HeLa Cells

First human continuous cell line, derived from Henrietta Lacks’ cervical tumor in 1951.

Aseptic Technique

Sterile practices (e.g., laminar-flow hood use) to minimize microbial contamination in tissue culture.

Confluency

Percentage of the culture surface covered by adherent cells; optimal sub-culture at 70–80 %.

Passage Number

Count of how many times a cell population has been detached and re-plated since isolation.

Trypsin/EDTA

Enzymatic solution used to detach adherent cells; trypsin cleaves ECM proteins, EDTA chelates Ca²⁺.

Hayflick’s Phenomenon

Finite replicative limit of normal somatic cells in culture, followed by senescence.

Senescence

State in which cells permanently stop dividing despite adequate nutrients and conditions.

Cryopreservation

Long-term storage of cells below −130 °C (often in liquid nitrogen) to halt metabolic activity.

Dimethyl Sulfoxide (DMSO)

Cryoprotectant that reduces ice-crystal damage but is toxic; must be removed quickly after thawing.

Cell Culture Hood

Laminar-flow cabinet providing sterile, filtered air for safe cell-handling procedures.

Incubator (37 °C, 5 % CO₂)

Controlled environment chamber supplying temperature, humidity, and CO₂ for optimal cell growth.

Hemacytometer / Cell Counter

Device (manual or automated) used to determine cell concentration and viability.

Explant Culture

Technique where small tissue pieces are attached to a surface; cells migrate out and proliferate.

Enzymatic Dissociation

Use of proteolytic enzymes (e.g., trypsin, collagenase) to separate cells from tissue ECM.

Flow Cytometry

Technique measuring physical and fluorescent properties of cells; enables sorting (FACS).

FACS (Fluorescence-Activated Cell Sorting)

Flow-cytometric method that isolates specific cell populations using fluorescent antibodies.

Magnetic Separation

Isolation of cells via antibodies coupled to magnetic beads targeting surface antigens.

Cross-Contamination

Unintended mixing of different cell lines; leads to misidentified cultures.

Mycoplasma

Small bacteria lacking cell walls; common, hard-to-detect cell-culture contaminant identified by PCR.

Toxicity Testing

Assessment of drug or chemical effects on cultured cells to predict in-vivo toxicity.

Virus Cultivation

Growth of viruses in cell culture for vaccine production and life-cycle studies.

Cancer Research (in vitro)

Use of cultured cells to study oncogenic transformation by chemicals, radiation, or viruses.

Genetic Engineering (Cell Culture)

Production of recombinant proteins or viral vectors using cultured cells.

Gene Therapy

Replacement or correction of defective genes in patient cells cultured ex vivo.

Tissue Engineering

Generation of artificial tissues/organs via cell and scaffold culture technologies.

Fetal Bovine Serum (FBS)

Common media supplement containing growth factors, hormones, and binding proteins promoting proliferation.

Media Bulk Ions

Essential electrolytes in culture medium, e.g., Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl⁻, HCO₃⁻.

Trace Elements

Minor nutrients (e.g., iron, zinc, selenium) required for cellular enzyme function in culture.

Stem Cell

Immature, unspecialised cell capable of self-renewal and differentiation into specialized cell types.

Totipotent Stem Cell

Cell able to generate all embryonic and extra-embryonic cell types (e.g., zygote, morula).

Pluripotent Stem Cell

Cell able to form all embryonic germ-layer derivatives (e.g., inner cell mass, ESCs, iPSCs).

Multipotent Stem Cell

Adult stem cell capable of producing multiple, but limited, cell types within a tissue lineage.

Oligopotent Stem Cell

Progenitor restricted to a few closely related cell types.

Unipotent Cell

Differentiated cell with capacity to self-renew but generate only its own cell type.

Embryonic Stem Cells (ESCs)

Pluripotent cells isolated from the inner cell mass of the blastocyst.

Adult Stem Cells

Multipotent, tissue-specific cells residing in adult organs for repair and maintenance.

Induced Pluripotent Stem Cells (iPSCs)

Somatic cells reprogrammed to pluripotency by expression of factors such as OCT4, SOX2, KLF4, c-MYC.

Self-Renewal

Stem-cell property of producing at least one identical daughter stem cell upon division.

Differentiation

Process by which stem or progenitor cells mature into specialized cell types.

Mesenchymal Stem Cells (MSCs)

Multipotent stromal cells (e.g., bone marrow) forming bone, cartilage, fat, muscle; possess immunomodulatory effects.

Symmetric Division

Cell division producing two identical daughter cells (both stem or both differentiated).

Asymmetric Division

Stem-cell division yielding one stem cell and one progenitor/differentiated cell.

Stem Cell Therapy (Burn Treatment)

Use of cultured keratinocyte sheets derived from patient skin stem cells for third-degree burn repair.

Stem-Cell Drug Screening

Testing candidate compounds on disease-specific iPSC-derived cells to discover therapeutics.