Thyroid Hormones and Their Interactions with Immune System in Birds Jianan(Jane)LIU 2008-3-3

Objectives What are thyroid hormones in birds? How do they work? What are the effects of thyroid hormones in birds? What are the interactions between thyroid hormones and the immune system in birds?

What are thyroid hormones in birds?

How do they work?

What are the effects of thyroid hormones in birds?

What are the interactions between thyroid hormones and the immune system in birds?

Thyroid Hormones in Birds

Thyroid Hormones Triiodothyronine Functionally Active ？ T 3 Thyroxine Quantitatively Predominant T 4 Deiodination

Thyroxine (T 4 ) Triiodothyronine (T3)

How do they work in birds? Initiation & Activation

Hypothalamic-Pituitary-Thyroid (HPT) Axis Hypothalamus Anterior Pituitary Thyroid Gland Plasma Thyrotropin-releasing hormone (TRH) Thyrotropin (TSH) T 3 & T 4 Feedback

Thyroid Hormone Activation TR=T 3 Receptor RXR=Retinoid X Receptor TRE=Thyroid Hormone Response Element Co?=Co-activator(s) or Co-repressor(s) Cytoplasm T 3 T 3 T 3 Nucleus TRE TR RXR Co? Changing in expression DNA

What roles do they play in birds?

Multiplicity of Thyroid Hormone Action Thyroid Hormones

Multiplicity of Thyroid Hormone Action Thyroid Hormones Metabolism （ Thermoregulation ）

Multiplicity of Thyroid Hormone Action Metabolism （ Thermoregulation ） Thyroid Hormones Development (Growth+Maturation)

Multiplicity of Thyroid Hormone Action Development (Growth+Maturation) Metabolism （ Thermoregulation ） Thyroid Hormones Reproduction Behavior

Multiplicity of Thyroid Hormone Action Immunity Development (Growth+Maturation) Metabolism （ Thermoregulation ） Behavior Reproduction Thyroid Hormones

Immune-Thyroid Networks

Studies on Thyroid Hormone & Immune System Bourgeon and Ralot (2007) Suppression in humoral immunity Birds Silberman et al. (2002) Lymphocyte proliferative response Mice Fort et al. (2007) Metamorphic-based changes in immune function Frogs S.H.Lam et al. (2005) Thymus development Lymphopoiesis Zebra Fish Literature Effects Model Organisms

Thyroid Hormone & Immune System Leukocyte (Cytokine) TSH Thyroid Gland (T 3 & T 4 ) Immune System HPT Axis Producing Feedback stimulating Cytokine-like Regulating

Summary Thyroid homes Thyroxine(T 4 ) Triiodothyronine (T 3 ) Initiation and Activation HPT axis Thyroid hormone receptor (TR) Thyroid hormone response element(TRE) Multiplicity in birds’ lives Immune-thyroid interactions

Thyroid homes

Thyroxine(T 4 )

Triiodothyronine (T 3 )

Initiation and Activation

HPT axis

Thyroid hormone receptor (TR)

Thyroid hormone response element(TRE)

Multiplicity in birds’ lives

Immune-thyroid interactions

Thank You