Intro / Cells & Tissues of the Immune Response Flashcards
Helper T cells have _____ CD proteins.
CD4+
Which cytokines do plasmacytoid dendritic cells produce?
interferon-alpha (IFNa)
Interferon-beta (IFNb)
Which portion of the thymis is densely packed with immature T cells?
The cortex
Where can mast cells be found?
Rarely identified in peripheral blood
Present within dermal and mucosal tissues
This CD protein is common to all T lymphocytes.
CD3
What do conventional dendritic cells do?
They play critical roles in activating naive T lymphocytes
The second most abundant circulating leukocyte.
Monocytes
What are dendritic cells?
Matured monocyte. Antigen Presenting Cell (APC). Their main function is to process antigen material and present it on the cell surface to the T cells of the immune system.
Which type of T cells are largely absent from the circulation and localized preferentially in mucosal surfaces?
γδ T cells
About how long do neutrophils circulate?
6 hours
In a parasitic infection, you would have high levels of what?
Eosinophils
Which cytokines, produced in response to parasite infections, are responsible for the differentiation of myeloid precursor cells into eosinophils?
GM-CSF
IL3
IL5
What do plasmacytoid dendritic cells do?
They play important roles in anti-biral immune responses
What are the lingual tonsils?
behind the terminal tongue underlie a non-keratinized squamous epithelium and possess characterist long branched and unbranched crypts
Spherical cells betweens 12-15 µm in diamter with numerous membrane extensions
Neutrophil
Which cells are a rich source of histamine and heparin?
Mast cells
Why don’t neutrophils stain very robustly with hematoxylin or eosin?
Their proteins are not particularly acidic or basic
This cell has a lobate nucleus, with 3-5 lobes
Neutrophil
What are thymocytes?
Immature T cells
Fraction in peripheral blood?
PMNs (neutrophils)
34-71%
Why are the grandule components in mast cells, basophils, and eosinophils readily identifiable through diagnostic dyes and stains?
The granule components are highly charged.
The predominant cell type in later phases of the inflammation.
Macrophages
Within which part of the thymus do thymocytes mature to become immunocompetent T cells?
Medulla
Neutrophils arise from a hematopoietic precursor cell stimulated with the cytokine ________.
G-CSF
What is clonal expansion?
The proliferation of specific lymphocytes that recognize a single antigenic epitope
Fraction in peripheral blood?
Monocytes
5-12%
What are adenoids?
pharyngeal tonsils
What are palatine tonsils?
Between the palatoglossal and palatopharyngeal arches of the oropharynx
What is central tolerance?
Positive and negative selection of T cells in the thymus
Waldeyer’s tonsillar ring
oral-nasopharyngeal tonsils, first line of defense against ingested or inhaeld antigens and pathogens
rich follicles with germinal centers
tubal, adenoids, palatine, lingual tonsils
Fraction in peripheral blood?
Eosinophils
0-7%
Fraction in peripheral blood?
Leukocytes
100%
Which cells survive longer: macrophages or neutrophils?
Macrophages
Cytolytic T cells have ______ proteins.
CD8
What are tubal tonsils?
located on the roof of the pharynx and are comprised of a partially capsulated lymphoid aggregates subjacent to a ciliated pseudostratified columnar epithelium
The majority of T cells express which type of T cell receptor?
αβ TCR
The most abundant circulating leukocyte
Neutrophils
List the granulocytes.
MBEN
(mast cells, basophils, eosinophils, neutrophils)
Defects in central tolerance lead to immune responses against self-tissue…a process known as
Autoimmunity
Sequential series of steps that phagocytes go through to remove invading micro-organisms
Recruitment
Recognition-Activation
Phagocytosis
Regulation
These cells mediate the earliest, most immediate phases of innate immunity.
Neutrophils
What are the only cells in the body that express clonally distributed antigen receptors?
Lymphocytes
These CD proteins are typical of almost all B cells.
CD19 and CD20
List the agranulocytes.
Monocytes
Lymphocytes
What are the lymphocyte subsets?
T cells
B cells
Natural killer cells (NK)
NK-T cells (rare and little understood)
Fraction in peripheral blood?
Basophils
0-1%
Which cytokine is responsible for the maturation of dendritic cells?
Flt3-ligand
The 2 types of phagocytic immune cells are:
Neutrophils (PMNs)
Monocytes/macrophages
Fraction in peripheral blood?
Lymphocytes
19-53%
What do plasma cells in the gut produce?
IgA
Which antibodies are abundant in the external skin environment?
IgA and IgG
intraepidermal lymphocytes (IELs)
immune sentinels within the epidermal surface
