Related Experiment Video

Updated: Aug 17, 2026

Preparation and Use of HIV-1 Infected Primary CD4+ T-Cells as Target Cells in Natural Killer Cell Cytotoxic Assays
12:07

Preparation and Use of HIV-1 Infected Primary CD4+ T-Cells as Target Cells in Natural Killer Cell Cytotoxic Assays

Published on: March 14, 2011

Tumor necrosis factor and lymphotoxin secretion by human natural killer cells leads to antiviral cytotoxicity

C V Paya1, N Kenmotsu, R A Schoon

  • 1Department of Immunology, Mayo Clinic and Foundation, Rochester, MN 55905.

Journal of Immunology (Baltimore, Md. : 1950)
|September 15, 1988
PubMed

Insights

Natural killer (NK) cells combat viral infections by secreting tumor necrosis factor (TNF) and lymphotoxin. These proteins selectively kill virus-infected cells, contributing to antiviral immunity.

Area of Science:

  • Immunology
  • Virology
  • Cell Biology

Background:

  • Natural killer (NK) cells are crucial for innate immunity, primarily known for their role in tumor cell cytotoxicity.
  • The specific mechanisms by which NK cells mediate antiviral immunity are not fully elucidated.

Purpose of the Study:

  • To investigate the role of specific proteins secreted by NK cells in antiviral immunity.
  • To identify the soluble factors responsible for NK cell-mediated killing of virally infected cells.

Main Methods:

  • Human CD16+/CD3- NK cells were isolated using fluorescence-activated cell sorting (FACS) and cloned via limiting dilution.
  • NK cell supernatants were tested for antiviral activity against vesicular stomatitis virus (VSV)-infected cells.
  • The effect of antibodies against tumor necrosis factor (TNF) and lymphotoxin on antiviral activity was assessed.
  • Recombinant human TNF was used to confirm its cytotoxic effects on various virus-infected cells.

Main Results:

  • NK cell lines exhibited cytotoxicity against both tumor and virally infected cells.
  • NK cell supernatants selectively killed VSV-infected cells while sparing uninfected cells.
  • This soluble antiviral activity was neutralized by antibodies against TNF and lymphotoxin.
  • Recombinant TNF demonstrated specific cytotoxicity against VSV, CMV, Theiler's murine encephalomyelitis virus, and HSV-infected cells, with variations depending on the virus and cell type.

Conclusions:

  • NK cells can mediate direct and selective cytotoxicity against virally infected cells.
  • Tumor necrosis factor (TNF) and lymphotoxin are key secreted proteins responsible for this NK cell-mediated antiviral effect.

More Related Videos

A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity06:08

A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity

Published on: August 9, 2017

Measurement of Natural Killer Cell-Mediated Cytotoxicity and Migration in the Context of Hepatic Tumor Cells06:55

Measurement of Natural Killer Cell-Mediated Cytotoxicity and Migration in the Context of Hepatic Tumor Cells

Published on: February 22, 2020

Related Concept Videos

Cells of the Innate Immune Response01:28

Cells of the Innate Immune Response

The innate immune response is an immediate and non-specific response against pathogens, acting swiftly to prevent the spread of infections. The primary cells involved in this response are phagocytes and natural killer (NK) cells.
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
Immune Surveillance by NK Cells and Phagocytes01:25

Immune Surveillance by NK Cells and Phagocytes

Immune surveillance is an integral part of the innate immune system, involving the continuous monitoring of peripheral tissues to detect and respond to pathogens, infected cells, or cancerous cells. This surveillance is conducted primarily by natural killer (NK) cells and phagocytes, which employ distinct but complementary mechanisms to identify and eliminate threats.
Natural Killer Cells: The Fast Responders
NK cells are large granular lymphocytes found in the blood and lymphatic system. These...
T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Cytotoxic T Cells-mediated Immune Response01:27

Cytotoxic T Cells-mediated Immune Response

Cytotoxic T cells are a vital component of the immune system. They have the remarkable ability to identify and target antigens on infected or abnormal cells. These antigens often originate from intracellular pathogens such as viruses or abnormal proteins cancer cells produce.
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
Immune Response Against Viral Pathogens01:29

Immune Response Against Viral Pathogens

The immune system's response to viral infections is a complex and coordinated process involving natural killer (NK) cells, T cell-mediated responses, and antibody-mediated responses.
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
Tumor Immunotherapy01:27

Tumor Immunotherapy

Immunotherapy is a treatment that boosts or manipulates the immune system to fight diseases, including cancer. For instance, by stimulating an immune response through vaccinations against viruses that cause cancers, like hepatitis B virus and human papillomavirus, these diseases can be prevented. Nonetheless, some cancer cells can avoid the immune system due to their rapid mutation and division. The immune response to many cancers involves three phases: elimination, equilibrium, and escape.