Related Experiment Video

Updated: Jun 12, 2026

Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens
08:47

Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens

Published on: April 5, 2019

IL-7-dependent B lymphocytes are essential for the anti-polysaccharide response and protective immunity to

Anne K Shriner1, Hongqi Liu, Guizhi Sun

  • 1Department of Microbiology and Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.

Journal of Immunology (Baltimore, Md. : 1950)
|May 28, 2010
PubMed

Insights

Interleukin-7 (IL-7) signaling is crucial for young children's antibody responses to T cell-independent (TI) antigens like pneumococcal polysaccharide (PPS). Activating IL-7 pathways can restore these impaired immune responses in the young.

Area of Science:

  • Immunology
  • Pediatric immunology
  • Vaccinology

Background:

  • Young children exhibit impaired antibody responses to T cell-independent (TI) antigens, such as pneumococcal polysaccharide (PPS).
  • B lymphopoiesis, the development of B cells, is IL-7 independent in early life but IL-7 dependent in adulthood.
  • IL-7 signaling is hypothesized to be critical for effective antibody responses to TI antigens.

Purpose of the Study:

  • To investigate the role of IL-7-driven B lymphopoiesis in promoting antibody responses to TI antigens in young versus adult mice.
  • To determine if IL-7-dependent B cells are essential for immunity against TI antigens and bacterial challenge.

Main Methods:

  • Comparison of immune responses to PPS vaccination and a model TI antigen (4-hydroxy-3-nitrophenyl-acetyl-Ficoll) in young and adult wild-type mice.
  • Assessment of TI responses in young or adult mice deficient in IL-7 or IL-7Ralpha.
  • Evaluation of TI responses in young IL-7 transgenic mice with enhanced IL-7 signaling.
  • Testing resistance to Streptococcus pneumoniae challenge in various mouse models.

Main Results:

  • Mice deficient in IL-7 or IL-7Ralpha showed severely impaired anti-PPS responses and did not survive S. pneumoniae challenge, indicating a requirement for IL-7-dependent B cells in TI immunity.
  • Young IL-7 transgenic mice exhibited robust TI responses to PPS immunization, comparable to adult wild-type mice.
  • Immunized young or adult IL-7 transgenic mice were completely resistant to S. pneumoniae challenge.

Conclusions:

  • IL-7-dependent B cells are essential for mounting effective antibody responses to TI antigens and for protection against Streptococcus pneumoniae infection.
  • Activating the IL-7 signaling pathway can restore impaired TI responses in young individuals.
  • These findings highlight the potential of targeting IL-7 signaling to enhance pediatric immunity to TI antigens.

More Related Videos

Unraveling Key Players of Humoral Immunity: Advanced and Optimized Lymphocyte Isolation Protocol from Murine Peyer's Patches08:25

Unraveling Key Players of Humoral Immunity: Advanced and Optimized Lymphocyte Isolation Protocol from Murine Peyer's Patches

Published on: November 21, 2018

Characterization of Thymus-dependent and Thymus-independent Immunoglobulin Isotype Responses in Mice Using Enzyme-linked Immunosorbent Assay06:15

Characterization of Thymus-dependent and Thymus-independent Immunoglobulin Isotype Responses in Mice Using Enzyme-linked Immunosorbent Assay

Published on: September 7, 2018

Related Concept Videos

B Cell Activation and Differentiation01:24

B Cell Activation and Differentiation

The adaptive immune response, a sophisticated defense mechanism, relies on the activation and differentiation of B lymphocytes, or B cells. These processes enable our bodies to mount a tailored response against specific pathogens such as bacteria, free virus particles, toxins, and parasites.
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Humoral Immune Responses01:36

Humoral Immune Responses

Overview
Special Features of Adaptive Immunity01:20

Special Features of Adaptive Immunity

The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
Cell-mediated Immune Responses01:40

Cell-mediated Immune Responses

Overview
Cells of the Adaptive Immune Response01:23

Cells of the Adaptive Immune Response

The T and B lymphocytes of the adaptive immune system develop from common lymphoid progenitor cells in the bone marrow. These progenitors give rise to precursors that eventually develop into both T and B lymphocytes. As these precursors mature, they gain the ability to detect and respond to foreign antigens in the body, a process known as immunocompetence. Additionally, these precursors acquire self-tolerance, a process that ensures they do not react to self-antigens. This intricate system...