Related Experiment Video

Updated: May 28, 2026

Study of Dendritic Cell Development by Short Hairpin RNA-Mediated Gene Knockdown in a Hematopoietic Stem and Progenitor Cell Line In vitro
06:12

Study of Dendritic Cell Development by Short Hairpin RNA-Mediated Gene Knockdown in a Hematopoietic Stem and Progenitor Cell Line In vitro

Published on: March 7, 2022

The matricellular protein SPARC supports follicular dendritic cell networking toward Th17 responses

Silvia Piconese1, Massimo Costanza, Claudio Tripodo

  • 1Molecular Immunology Unit, Department of Experimental Oncology and Molecular Medicine, AmadeoLab, Fondazione IRCCS Istituto Nazionale Tumori, via Amadeo 42, 20133 Milan, Italy.

Journal of Autoimmunity
|October 4, 2011
PubMed

Insights

Secreted protein acidic and rich in cysteine (SPARC) is crucial for germinal center formation and T helper 17 (Th17) cell differentiation during immune responses. SPARC optimizes interactions between follicular dendritic cells, B cells, and Th17 cells in lymph nodes.

Area of Science:

  • Immunology
  • Cell Biology
  • Extracellular Matrix Biology

Background:

  • Lymph node swelling involves dynamic extracellular matrix remodeling during immune responses.
  • The role of SPARC in regulating lymph node architecture and immune cell interactions is not fully understood.

Purpose of the Study:

  • To investigate the function of SPARC in germinal center formation and T helper 17 (Th17) cell differentiation.
  • To elucidate the role of SPARC in the crosstalk between follicular dendritic cells (FDCs), B cells, and Th17 cells.

Main Methods:

  • Analysis of SPARC expression in murine and human reactive lymph nodes.
  • Assessment of germinal center formation and humoral autoimmunity in SPARC-deficient mice.
  • Evaluation of Th17 cell differentiation and experimental autoimmune encephalomyelitis (EAE) development in SPARC-deficient models.
  • In vivo studies to identify SPARC-producing cells.

Main Results:

  • SPARC is expressed in germinal centers of reactive lymph nodes.
  • SPARC-deficient mice exhibit delayed germinal center arrangement, impaired FDC networking, and development of humoral autoimmunity linked to Th17 development.
  • SPARC is essential for optimal Th17 cell differentiation and EAE development.
  • Both radioresistant cells (FDCs) and CD4+ cells are sources of SPARC in vivo.
  • Th17 cell entry into germinal centers is dependent on SPARC.

Conclusions:

  • SPARC plays a critical role in optimizing lymphoid extracellular matrix changes, facilitating functional crosstalk between FDCs, B cells, and Th17 cells.
  • SPARC is indispensable for efficient germinal center formation and Th17 cell differentiation, impacting humoral immunity and autoimmune responses.

More Related Videos

Assessing the Development of Murine Plasmacytoid Dendritic Cells in Peyer's Patches Using Adoptive Transfer of Hematopoietic Progenitors13:34

Assessing the Development of Murine Plasmacytoid Dendritic Cells in Peyer's Patches Using Adoptive Transfer of Hematopoietic Progenitors

Published on: March 17, 2014

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...
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...
Paracrine Signaling01:21

Paracrine Signaling

Paracrine signaling allows cells to communicate with their immediate neighbors via secretion of signaling molecules. Such a signal can only trigger a response in nearby target cells because the signal molecules degrade quickly or are inactivated if not taken up. Prominent examples of paracrine signaling include nitric oxide signaling in blood vessels, synaptic signaling of neurons, the blood clotting system, tissue repair/wound healing, and local allergic skin reactions. Nitric oxide as a...
Paracrine Signaling01:21

Paracrine Signaling

Paracrine signaling allows cells to communicate with their immediate neighbors via secretion of signaling molecules. Such a signal can only trigger a response in nearby target cells because the signal molecules degrade quickly or are inactivated if not taken up. Prominent examples of paracrine signaling include nitric oxide signaling in blood vessels, synaptic signaling of neurons, the blood clotting system, tissue repair/wound healing, and local allergic skin reactions. Nitric oxide as a...
T Cell Activation and Clonal Selection01:22

T Cell Activation and Clonal Selection

T cells are integral to our adaptive immune system, recognizing and effectively responding to foreign antigens. T cell activation and clonal selection are pivotal in orchestrating this immune response. This article elucidates these mechanisms, detailing the roles of cluster of differentiation (CD) markers, major histocompatibility complex (MHC) molecules, costimulatory signals, and the process of clonal selection.
Naive T cells that have not yet encountered an antigen express two primary CD...
Regulation of Hematopoietic Stem Cells01:01

Regulation of Hematopoietic Stem Cells

All blood and immune cells are produced from the multipotent hematopoietic stem cells (HSCs) by the process of hematopoiesis. However, they all have a limited life span. In addition, many are depleted in immune surveillance or combatting an injury or infection. This makes blood one of the most regenerative tissues. Hematopoiesis helps replenish these blood and immune cells, restoring the body's normal functioning. However, overproduction of blood and immune cells can make them cancerous or...