INVESTIGADORES
SUSPERREGUY Sebastian
congresos y reuniones científicas
Título:
IMPACT OF THYROID HORMONES IN THE INITIATION OF THE IMMUNE RESPONSE: EVIDENCE FOR THYROID HORMONE RECEPTOR EXPRESSION IN BONE MARROW-DERIVED MOUSE DENDRITIC CELLS
Autor/es:
RAMSEYER V; SUSPERREGUY S; CERVI L; MONTESINOS M,; DE PAUL A; MUKDSI J; TORRES A; COLEONI A; RABINOVICH G; PELLIZAS C.
Lugar:
Octubre 30-Noviembre 4, 2005- Bs As. Argentina.
Reunión:
Congreso; 13 th Internacional Thyroid Congress; 2005
Resumen:
Homeostatic regulation of the immune response involves
factors such as hormones and a functional cross-talk between the endocrine and
the immune systems has been well documented. To date, most studies on this
relationship were directed mainly to address the role of adrenal hormones and
the CRH/ACTH/glucocorticoid axis, whereas scarce information has been obtained
regarding the role of thyroid hormones (TH) in immunity; and in fact such
studies were mostly conducted on B and T lymphocytes. The majority of TH
effects are exerted through TH receptors (TR) which are ligand inducible
transcription factors that bind to target genes. The role of
antigen presenting cells (APC) is mainly played by dendritic cells (DC) because
of their ability to initiate, activate and regulate the immune response. DC are
the only APC that stimulate naive T cells and initiate primary immune
responses. In vitro, DC can be generated from bone marrow (immature DC), with a
retained capability for uptaking and processing antigens. The exposure of these
cells to pro-inflammatory stimuli, generates mature DC able to stimulate T
cells. The impact of TH on DC functionality still remains unknown. The aim of
the present study was to investigate the presence of TR and TR mRNA in DC to
forecast TH effects at this level. Mice DC were cultured from bone marrow in
the presence of GM-CSF for 7 days. For activation, DC were pulsed with 10 µg/ml
lipopolysaccharide (LPS) for the final 18 h of culture. Cells were harvested
and TR revealed by immunocytochemistry and TR mRNA by RT-PCR. Results indicated
that TR are expressed at both the protein and mRNA levels in immature and
mature DC, albeit at lower levels to those expressed on T and B cells. The
presence of TR in DC strongly hints that some specific functions of these cells
are regulated by TH. Further studies should provide evidence of TR-regulated DC
genes and the function of TH on DC functionality, immunogenicity and tolerance.