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Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery

Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery

Published on: November 5, 2019

T-cell responses against meningococcal antigens.

L M Næss¹, F Oftung, A Aase

¹Department of Vaccinology, National Institute of Public Health, Oslo, Norway.

Methods in Molecular Medicine

|February 22, 2011

Summary

T-cells identify foreign peptides via major histocompatibility complex (MHC) molecules on antigen-presenting cells (APCs). CD4+ T helper cells, crucial for adaptive immunity, differentiate into Th1 or Th2 subsets with distinct cytokine profiles.

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Generation of Human Alloantigen-specific T Cells from Peripheral Blood

Generation of Human Alloantigen-specific T Cells from Peripheral Blood

Published on: November 21, 2014

Area of Science:

Immunology
Cellular Biology
Molecular Biology

Background:

T-cells recognize peptide fragments bound to MHC molecules on APCs.
Antigen uptake, processing, and MHC-peptide complex presentation are vital for T-cell activation.
CD8+ T-cells recognize endogenous antigens via MHC class I, while CD4+ T-cells recognize exogenous antigens via MHC class II.

Purpose of the Study:

To elucidate the distinct roles and characteristics of CD4+ T helper cell subsets (Th1 and Th2).
To understand how extracellular pathogens are presented to CD4+ T cells.
To detail the cytokine production and effector functions of Th1 and Th2 cells.

Main Methods:

Analysis of T-cell antigen recognition pathways.
Investigation of antigen processing by professional APCs (B cells, macrophages, dendritic cells).
Characterization of cytokine profiles (IL-2, IFN-γ, TNF-β for Th1; IL-4, IL-5, IL-6, IL-13 for Th2).

Main Results:

Extracellular bacteria are presented to CD4+ T cells via MHC class II molecules.
Th1 cells produce cytokines that induce cell-mediated immunity and activate macrophages.
Th2 cells produce cytokines that regulate B-cell responses.

Conclusions:

CD4+ T helper cells are classified into Th1 and Th2 subpopulations based on distinct cytokine production and functions.
Th1 responses are crucial for combating intracellular pathogens, while Th2 responses are important for extracellular pathogens.
IFN-γ (Th1) enhances macrophage microbicidal activity, whereas Th2 cytokines regulate humoral immunity.