Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Lytic units reconsidered: pitfalls in calculation and usage.

R E Pollock1, S O Zimmerman, P Fuchshuber

  • 1Department of General Surgery, University of Texas M. D. Anderson Cancer Center, Houston 77030.

Journal of Clinical Laboratory Analysis
|January 1, 1990
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Canadian Surgery Forum: Abstracts of presentations to the Annual Meetings of the Canadian Association of Bariatric Physicians and Surgeons, Canadian Association of General Surgeons, Canadian Association of Thoracic Surgeons, Canadian Hepato-Pancreato-Biliary Association, Canadian Society of Surgical Oncology, Canadian Society of Colon and Rectal Surgeons, Vancouver, BC, Sept. 17-21, 2013.

Canadian journal of surgery. Journal canadien de chirurgie·2025
Same author

The SAGES Fundamental Use of Surgical Energy program (FUSE): history, development, and purpose.

Surgical endoscopy·2017
Same author

Verticillin A Inhibits Leiomyosarcoma and Malignant Peripheral Nerve Sheath Tumor Growth via Induction of Apoptosis.

Clinical & experimental pharmacology·2017
Same author

Lymphokine-activated killer cell activity Characteristics of effector cells and their progenitors in blood and spleen.

Immunology today·2014
Same author

Safety and outcome of combined liver and pancreatic resections.

The British journal of surgery·2014
Same author

Molecular prognosticators of complex karyotype soft tissue sarcoma outcome: a tissue microarray-based study.

Annals of oncology : official journal of the European Society for Medical Oncology·2009
Same journal

Organ-Specific Human Microbiomes and Dysbiosis: Mechanistic Links to Disease and Emerging Therapeutic Strategies.

Journal of clinical laboratory analysis·2026
Same journal

Measurement of Plasma Free Hemoglobin Using the Hemolysis Index of the Mindray BS-800.

Journal of clinical laboratory analysis·2026
Same journal

IGFBP3 As a Potential Biomarker and Therapeutic Target in Hepatocellular Carcinoma: A Multi-Cohort Analysis.

Journal of clinical laboratory analysis·2026
Same journal

Optimization of Reflex Testing Rules on the Sysmex XN-9100 Automated Hematology Line Improves Efficiency and Reduces Repeat Testing in Different Work Areas.

Journal of clinical laboratory analysis·2026
Same journal

sFlt-1/PlGF Ratio in the Diagnosis of Preeclampsia on the MAGLUMI X3 Analyzer.

Journal of clinical laboratory analysis·2026
Same journal

Application of Cell-Free DNA Barcode-Enabled Single-Molecule Test for Non-Invasive Prenatal Testing of α-Thalassemia and β-Thalassemia.

Journal of clinical laboratory analysis·2026
See all related articles

The lytic unit, commonly used to quantify cell-mediated cytotoxicity, can inaccurately represent experimental data due to flawed biomathematical models. Researchers should consider alternative methods for more reliable cytotoxicity comparisons.

Area of Science:

  • Immunology
  • Biomathematics
  • Cancer Research

Background:

  • Cytotoxicity data, often derived from 51Chromium release assays, typically presents as curvilinear plots.
  • Biomathematical models, including simple linear regression, exponential fit, and Von Krogh, are used to convert these curves into a single value, the lytic unit.
  • Lytic units are widely adopted in immune studies involving natural killer cells, lymphokine-activated killer cells, and cytotoxic T cells for data presentation.

Purpose of the Study:

  • To evaluate the accuracy of biomathematical models used for calculating lytic units from cytotoxicity data.
  • To identify potential sources of error in lytic unit determination and inter-donor comparisons.
  • To recommend alternative approaches for more reliable cytotoxicity data analysis.

Main Methods:

Related Experiment Videos

  • Analysis of biomathematical models (simple linear regression, exponential fit, Von Krogh) used for lytic unit calculation.
  • Comparison of model-predicted cytotoxicity with actual observed data.
  • Statistical evaluation of assumption violations in comparative analyses.

Main Results:

  • Biomathematical models for lytic unit determination can yield inaccurate cytotoxicity predictions compared to observed data.
  • Even accurate models, like the three-parameter Von Krogh model, can lead to errors in inter-donor comparisons due to violated assumptions of parallelism.
  • Direct comparison of cytotoxicity across a range of effector:target ratios avoids these statistical issues.

Conclusions:

  • The use of lytic units may introduce significant inaccuracies in the evaluation and reporting of cytotoxicity data.
  • Violations of statistical assumptions in lytic unit models can compromise the reliability of comparisons between different donors.
  • Researchers are advised to reconsider the utility of lytic units and explore alternative methods, such as direct ratio comparisons, for more robust data analysis.