Dictionary domainTrack F
Life sciences and biology
Vocabulary anchored in biological and life-sciences research disciplines.
Terms in this domain
16 terms
Human Cell Atlas (HCA)
An international, open-science consortium, founded in 2016 and convened by the Broad Institute, the Wellcome Sanger Institute, and Wellcome, that aims to create comprehensive reference maps of every cell type in the human body using single-cell and spatial genomics. The HCA is a distributed research collaboration organized into national/regional networks and topic-specific Biological Networks (not a repository, funder, or formal legal entity), coordinated by an Organizing Committee and Working Groups, publishing data and analysis tools through the HCA Data Portal for free public reuse under its own network-level standards.
Labguru
Labguru is a cloud-based ELN and LIMS platform from BioData Inc. that combines experiment documentation, sample and inventory tracking, and equipment management in one linked system: an experiment record can reference the exact inventory lot and instrument used, rather than those records living in separate tools.
Thermal Cycler Specifications
Thermal cycler specifications are the documented set of performance parameters — block format and sample capacity, ramp rate, temperature accuracy and uniformity, gradient range, lid control, and connectivity/data-logging features — that a manufacturer publishes for a PCR instrument and that a buyer uses to compare models against a specific assay's requirements. In a procurement context, a spec sheet is not a marketing document to skim; it is the primary evidence a lab manager or procurement officer can hold a vendor to, and it is what should be cross-checked against method validation records, accreditation requirements, and service contracts before an order is placed. A thermal cycler that is technically capable of amplifying DNA does not necessarily meet the documented performance a regulated or accredited lab needs for a specific application — that gap is exactly what a specifications comparison is meant to close.
Veterinary Cytology
Veterinary cytology is the diagnostic technique of collecting, preparing, staining, and microscopically examining individual cells (rather than intact tissue architecture, as in histopathology) obtained from an animal by fine-needle aspiration, impression smear, scraping, swab, or body-fluid sampling, in order to characterize a lesion, mass, effusion, or organ as inflammatory, infectious, hyperplastic, or neoplastic — and, for neoplastic samples, to assess features consistent with malignancy. A sample or workflow counts as veterinary cytology, in the operational sense used here, when it involves: (1) a minimally invasive collection method that disaggregates or exfoliates cells rather than removing an intact tissue block; (2) a rapid stain (commonly a Romanowsky-type stain such as Diff-Quik, Wright-Giemsa, or new methylene blue for fluids) applied to an air-dried or fixed smear; and (3) microscopic interpretation — performed in-house by a trained veterinarian or veterinary technician, or referred to a board-certified veterinary clinical pathologist (Diplomate, American College of Veterinary Pathologists, ACVP-Clinical Pathology) — that produces a cytologic diagnosis or descriptive report distinct from a surgical histopathology report. Procurement and lab-management decisions in this category generally split into two connected questions: what in-house capability (microscope, stains, slide-prep supplies, staff training) a practice or diagnostic lab maintains for first-pass or triage interpretation, and which reference laboratory or telecytology service it uses for definitive, board-certified review — most practices use both, routing straightforward or urgent cases in-house and referring diagnostically challenging, potentially malignant, or medicolegally significant samples out.
Xeno-Free Media
Xeno-free (XF) media is cell-culture medium formulated to contain no components derived from a species other than the one being cultured, used to eliminate the risk of xenogeneic contamination (viral, prion, and immunogenic non-human antigens) that comes with animal-derived supplements like fetal bovine serum. A product qualifies as xeno-free specifically when every raw material's species of origin has been checked against the cell type being grown -- human-derived components (e.g., human platelet lysate, human serum albumin) are permitted in xeno-free media intended for human cell culture, which is what distinguishes it from the stricter 'animal-component-free' (ACF) or 'animal-origin-free' (AOF) designation, where no animal-derived material of any species, including human, is used at all.
Unique Molecular Identifiers (UMIs)
Short, random or semi-random nucleotide sequences (typically 6-12 base pairs) added to individual DNA or RNA fragments during next-generation sequencing (NGS) library preparation, before PCR amplification, so that reads descended from the same original molecule can be identified and collapsed into a single consensus read.
Cryo-EM Microscope
A cryo-EM microscope is a transmission electron microscope purpose-built or fitted with an integrated cryogenic specimen workflow -- a cryo-transfer/autoloader system, a stable cryo-stage held below devitrification temperature, a field emission electron source, and (for modern structural-biology use) a direct electron detector and usually an energy filter -- so vitrified biological specimens can be imaged in a near-native, non-crystalline-ice state at near-atomic to atomic resolution. It depends on, but does not itself perform, upstream vitrification (plunge-freezing) of the specimen.
PhiX Control
PhiX control (PhiX Control v3) is an adapter-ligated sequencing library derived from the bacteriophage PhiX174 genome, spiked into Illumina NGS runs at a defined percentage to calibrate base-calling and error-rate metrics, and, at higher spike-in levels, to supply base-composition diversity that low-diversity libraries (e.g., amplicon panels, ChIP-seq, bisulfite sequencing) lack for reliable cluster calling and index demultiplexing.
Single-Use Assemblies (SUAs)
A single-use assembly (SUA) is a pre-fabricated, pre-sterilized fluid-path component -- typically some combination of flexible tubing, bags, connectors, filters, and sensors -- manufactured, irradiated, and supplied ready to install into a bioprocess for exactly one production run before being discarded rather than cleaned and reused. What separates an SUA from ordinary disposable plasticware is that it is qualified as a controlled process component: it comes with sterilization-validation and, for GMP or GMP-adjacent use, extractables-and-leachables documentation, rather than being purchased as a generic consumable on a certificate of conformance alone.
Chemically Defined Media (CDM)
Chemically defined media (CDM) is a cell-culture growth medium in which every component -- salts, amino acids, vitamins, lipids, and any protein supplements -- is a known, individually specified chemical entity added at a documented concentration, with no undefined biological components such as serum, hydrolysates, or tissue extracts. A formulation qualifies as CDM only when its full composition is disclosed and quantified, protein supplements (if present) are purified/recombinant and identified by expression source, and no ingredient is an undefined animal- or plant-derived mixture -- a medium that is merely 'serum-free' does not automatically meet this bar if it still contains an undefined hydrolysate or extract.
Fetal Bovine Serum (FBS)
Fetal bovine serum (FBS), also called fetal calf serum (FCS), is the liquid fraction of blood collected from bovine fetuses at slaughter, clarified and filtered for use as a growth-supporting supplement added to basal cell-culture media (typically 5-10% of final volume). It qualifies as FBS specifically when the source animal is a bovine fetus, distinguishing it from newborn calf serum (collected postnatally) and adult bovine serum (collected from mature cattle) -- both related but compositionally and functionally distinct products.
USP Class VI Certification
USP Class VI certification is a designation that a specific plastic material or component has passed the most stringent tier of biological reactivity testing under United States Pharmacopeia (USP) General Chapter , "Biological Reactivity Tests, In Vivo." Chapter defines six plastic classes (I through VI) based on which combination of three in-vivo bioassays -- systemic (acute) toxicity injection, intracutaneous reactivity, and implantation -- a material passes, and at what extraction rigor. A material reaches Class VI, the highest of the six classes, only when it passes all three bioassays using extracts prepared at the most demanding temperature/duration condition the material can withstand without degrading. Certification is specific to a tested formulation and manufacturing process, not a general property of a polymer family: it is not automatically inherited by variants, colorants, regrind blends, or downstream-sterilized versions of the same base resin, and passing Class VI does not by itself satisfy the broader ISO 10993 biocompatibility program most finished medical devices require.
Biospecimen
A biospecimen is a biological material — such as blood, tissue, urine, saliva, or a derived product like extracted DNA/RNA, plasma, or a cell line — that has been collected from a human or other living source and preserved under a documented chain of custody for use in research, clinical testing, or long-term storage in a biorepository or biobank. What distinguishes a biospecimen from a routine clinical sample is retention beyond the point of care: it is collected, labeled, and stored specifically so that it (or data derived from it) can be used again, often by someone other than the original collector, under a defined protocol and consent framework.
Specific Pathogen-Free (SPF) Mice
A colony or shipment of mice qualifies as specific pathogen-free (SPF) when it is bred and housed in a barrier facility and is documented, through a formal, periodic health-monitoring program, to be free of a defined list of excluded microorganisms and parasites (the 'exclusion list' or 'agent panel'). SPF is a relative, list-bound status, not a claim of total sterility: two colonies can both be validly called SPF while being screened against different panels, so the operative question for procurement and research use is always 'SPF with respect to which agent list, tested how recently, and by whom' rather than a single universal standard.
Gnotobiotic Mice
A mouse (or other laboratory animal) is gnotobiotic when its microbial status is completely known and controlled, rather than merely reduced or partially defined. This is a stricter standard than "clean": a gnotobiotic mouse is either (a) germ-free (axenic) — free of all detectable bacteria, fungi, viruses, and parasites — or (b) deliberately colonized with a specific, fully characterized set of microorganisms (the animal's defined "gnotobiote" community), with no other organisms present. The term comes from the Greek gnotos (known) plus bios (life) — literally "known life." Operationally, an animal only qualifies as gnotobiotic if all three of the following hold: it was derived by a method that excludes environmental microbial contamination (aseptic hysterectomy/hysterotomy or embryo transfer into a germ-free foster dam, followed by hand-rearing in isolation); it is housed for its entire life in a gnotobiotic isolator — a sealed, HEPA-filtered, positive- or negative-pressure enclosure with sterilized food, water, bedding, and air supply, entered only through a sterilizable transfer port or dunk tank; and its microbial status is periodically verified by culture-based and molecular (e.g., 16S rRNA sequencing, PCR) monitoring to confirm no unintended organisms have been introduced.
Biosafety Cabinet (BSC)
A biosafety cabinet (BSC) is a ventilated enclosure that uses HEPA filtration (removing at least 99.97% of particles 0.3 microns in diameter) combined with directional, certified airflow to contain biological aerosols generated during laboratory procedures. A device only counts as a biosafety cabinet, in the operational sense used across biosafety programs, if it (1) HEPA-filters air before it reaches the work surface, the exhaust, or both; (2) maintains inward airflow at its front opening (Class I and most Class II) or is fully gas-tight and glove-operated (Class III), so aerosols generated inside cannot reach the operator uncontrolled; and (3) has been performance-tested and field-certified — typically against NSF/ANSI 49 in the U.S. — rather than simply having a fan and a filter installed. Class I protects the worker and environment only; Class II protects the worker, product, and environment together and is the most common type in research and clinical microbiology labs; Class III is a gas-tight glovebox providing the highest level of containment, used for BSL-4 work. A biosafety cabinet is not a chemical fume hood (no certified chemical vapor containment unless specifically a Class II Type B cabinet) and is not a laminar flow "clean bench" (which protects only the sample and provides no worker protection at all).
