lymphocytes (T cells and B cells)

T cells (Thymus dependent)

Type of white blood cell, originate from stem cells in bone marrow and mature in Thymus, help fight infections and disease

B cells (Bone marrow derived)

White blood cells, Make infection fighting proteins called antibodies

natural killer cells

specialized type of white blood cell, fast acting defense system against virus and cancerous cells

how do T cells develop?

Start Immature in bone marrow, Travels thymus, Develops T cell receptor to recognize antigens, thymus checks if T cells can recognize MHC molecules, Matures, leaves thymus

what aids in T cell development?

Cortex divides, medulla, matures blood leaves

lymphocytes distribution

lymphocytes move through tissues and enter blood vessels or lymphatics for transport

where does the first population of lymphoid stem cells remain and develop?

In the bone marrow, with the help of Stromal cells

Stromal cells

Connective tissue cells form supportive, structural framework of organs, help maintain the health and function of active cells

which two specific types of immune cells are produced by lymphoid stem cells that stay in bone marrow

these cells and natural killer cells

exposure to which specific cytokine is required for B cells to differentiate

Interleukin-7

cytokine

secreted proteins released by cells, chemical messengers for, immune coordination, and inflammation

interlukin-7

vital cyantokine controls development, survival and homeostasis of T and B cells

where do bee cells and NK cells go once they mature in the bone marrow?

Enter circulation of bloodstream and migrate to peripheral tissues

where does the second population of lymphoid stem cells migrate to mature?

Thymus

what kind of cells do lymphoid stem cells in the thymus differentiate into?

T cells

And what kind of environment do T cells develop within thymus and what triggers their selection

Isolated from blood, selected with exposure to thymic hormones

MHC proteins

membrane glycoproteins that serve as “ signature” To identify the cell as self

where are MHC proteins coded?

Chromosome six

antigen presentation

Allows T cells to recognize and eliminate foreign threats

antigen presenting cells

specialized immune cells

antigen recognition

T cells have receptors that buying to MHC, receptors have specific binding sites

memory cells

Produced by the same cell division that produces cytotoxic T cells, Stays in circulation

regulatory T cells

Secrete inhibitory cytokines called suppression factors, Inhibit responses of TNB cells, initial immune response

what are the functions of cytokines secreted by helper T cells?

stimulates T cell division, attracts and stimulates macrophages, attracts and simulates the activity of cytotoxic T cells, promotes activation of B cells

what are the groups of cytokines

Interleukins, Interferons, Tumor necrosis factors, Phagocyte-activating chemicals, Colony-stimulating factors

what produces interleukins

lymphocytes, endothelial cells, fibroblasts and astrocytes

functions of interleukins

Increasing T cell sensitivity, Stimulating B cell , Enhancing innate immunity by stimulating, Moderating and shortening the immune function

why are interleukins (IL-1/IL-2) important stimulating and maintaining the immune response?

They activate and recruit other immune cells, creating a positive feedback loop that strengthens the immune response.

where are interferons produced

cells infected with a virus, fibroblasts and

N K cells

functions of interferons

Make the cells that produce them and cells resistant to vital infection, Attract and stimulate N K cells, Slow the progress of inflammation, Stimulate macrophages

where are Tumor necrosis factors

tivated macrophages and cytotoxic T cells

funcyions of Tumor necrosis factors

slow the growth of tumors and kill sensitive tumor cells, Stimulate granular leukocyte production, promote

eosinophil activity, cause fever, and increase T cell sensitivity to interleukins

What do phagocyte-activating cytokines do?

They coordinate immune defenses by changing the activity of phagocytes

What do some phagocyte-activating cytokines do?

They attract macrophages and microphages and keep them at the injury site.

What are colony-stimulating factors (CSFs)?

Cytokines that stimulate the production of blood cells

What do CSFs stimulate?