CXCR5 Expressing Human Central Memory CD4 T Cells and Their Relevance for Humoral Immune Responses.
Summary of "CXCR5 Expressing Human Central Memory CD4 T Cells and Their Relevance for Humoral Immune Responses."
High expression of CXCR5 is one of the defining hallmarks of T follicular helper cells (T(FH)), a CD4 Th cell subset that promotes germinal center reactions and the selection and affinity maturation of B cells. CXCR5 is also expressed on 20-25% of peripheral blood human central memory CD4 T cells (T(CM)), although the definitive function of these cells is not fully understood. The constitutive expression of CXCR5 on T(FH) cells and a fraction of circulating T(CM) suggests that CXCR5(+) T(CM) may represent a specialized subset of memory-type T(FH) cells programmed for homing to follicles and providing B cell help. To verify this assumption, we analyzed this cell population and show its specialized function in supporting humoral immune responses. Compared with their CXCR5(-) T(CM) counterparts, CXCR5(+) T(CM) expressed high levels of the chemokine CXCL13 and efficiently induced plasma cell differentiation and Ig secretion. We found that the distinct B cell helper qualities of CXCR5(+) T(CM) were mainly due to high ICOS expression and pronounced responsiveness to ICOS ligand costimulation together with large IL-10 secretion. Furthermore, B cell helper attributes of CXCR5(+) T(CM) were almost exclusively acquired on cognate interaction with B cells, but not with dendritic cells. This implies that a preferential recruitment of circulating CXCR5(+) T(CM) to CXCL13-rich B cell follicles is required for the promotion of a quick and efficient protective secondary humoral immune response. Taken together, we propose that CXCR5(+) T(CM) represent a distinct memory cell subset specialized in supporting Ab-mediated immune responses.
Immunology Program, Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia;
This article was published in the following journal.
Name: Journal of immunology (Baltimore, Md. : 1950)
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21471443
- DOI: http://dx.doi.org/10.4049/jimmunol.1002828
Although many relevant immune reactions are initiated in the lymph nodes, this compartment has not been systematically studied in humans. Analyses have been performed on immune cells derived from tons...
The number of memory phenotype CD8 T cells increases dramatically with aging in both humans and mice. However, the mechanism for this is unknown. The prevailing hypothesis is that memory T cells accum...
Long-lived antibody memory is mediated by the combined effects of long-lived plasma cells (PCs) and memory B cells generated in response to T cell-dependent antigens (Ags). IL-10 and IL-21 can activat...
Apart from their endocrine functions renin-expressing cells play an important functional role as mural cells of the developing preglomerular arteriolar vessel tree in the kidney. The recruitment of re...
The Kv1.3 voltage-gated potassium channel is selectively upregulated upon activation in effector memory T (TEM ) cells in inflamed tissue, and plays an important role in maintenance of T-cell activati...
The purpose of this study is to learn the safety and cancer-fighting effects of using IL-2 with the vaccines ("shots") made for you.
To evaluate the safety, toxicity and immunological effects of adjuvant administration of an experimental therapy consisting on priming with three intramuscular administrations of a plasmid...
This study investigates the use of the patients own immune cells to treat prostate cancer. Cells are taken from the patient and grown in the laboratory to become specialized immune cells c...
Rapid Transcranial Magnetic Stimulation will be used in order to examine whether the human primary visual cortex is essential to visual memory consolidation.
The investigators performed a 12-week, randomized, double-blind, placebo-controlled human trial to evaluate the efficacy and safety of Eriobotyra Japonica Lindley Extract on improvement of...
Medical and Biotech [MESH] Definitions
CXCR receptors isolated initially from BURKITT LYMPHOMA cells. CXCR5 receptors are expressed on mature, recirculating B-LYMPHOCYTES and are specific for CHEMOKINE CXCL13.
External envelope protein of the human immunodeficiency virus which is encoded by the HIV env gene. It has a molecular weight of 120 kDa and contains numerous glycosylation sites. Gp120 binds to cells expressing CD4 cell-surface antigens, most notably T4-lymphocytes and monocytes/macrophages. Gp120 has been shown to interfere with the normal function of CD4 and is at least partly responsible for the cytopathic effect of HIV.
Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory.
Cell-surface proteins that bind glutamate and trigger changes which influence the behavior of cells. Glutamate receptors include ionotropic receptors (AMPA, kainate, and N-methyl-D-aspartate receptors), which directly control ion channels, and metabotropic receptors which act through second messenger systems. Glutamate receptors are the most common mediators of fast excitatory synaptic transmission in the central nervous system. They have also been implicated in the mechanisms of memory and of many diseases.
A neurologic condition associated with the ACQUIRED IMMUNODEFICIENCY SYNDROME and characterized by impaired concentration and memory, slowness of hand movements, ATAXIA, incontinence, apathy, and gait difficulties associated with HIV-1 viral infection of the central nervous system. Pathologic examination of the brain reveals white matter rarefaction, perivascular infiltrates of lymphocytes, foamy macrophages, and multinucleated giant cells. (From Adams et al., Principles of Neurology, 6th ed, pp760-1; N Engl J Med, 1995 Apr 6;332(14):934-40)