Celleklumper

Celleklumper is a term used in biology to describe aggregates or clumps of cells that occur in various laboratory and clinical contexts. The word is rooted in Danish and Norwegian, where celle means cell and klumper means clump, and it is often used to refer to clusters formed in cell suspensions, digested tissues, or cytology preparations. In English-language literature the phenomenon is typically described as cell aggregates or cell clumps.

Celleklumper arise when cells adhere to each other or are not adequately dispersed during sample preparation. Factors that contribute include high cell density, strong cell–cell or cell–matrix adhesion, residual extracellular matrix, insufficient enzymatic digestion, mechanical stress during dissociation, and storage conditions. They can be observed in cultured cell suspensions, tissue-digestion outputs, and smears prepared from clinical samples.

The presence of cell clumps can affect downstream analyses. Clumping can bias single-cell measurements, complicate accurate counting and viability assessment, and interfere with flow cytometry gating or single-cell sequencing. It may also obscure individual cell morphology in microscopic evaluation. Conversely, intentionally formed aggregates, such as spheroids, are used in studies of cell–cell interactions and tumor biology.

Common strategies to reduce or control celleklumper include optimizing enzymatic dissociation (enzyme choice and exposure time), mechanical dispersion, adding DNase to reduce sticky extracellular DNA, filtering suspensions through cell strainers, and using anti-adhesion coatings or appropriate culture conditions. The term remains most prevalent in Nordic biomedical literature and protocols, where it is used alongside broader descriptors like cell aggregates.