Lecture 6- Immunodeficiency Flashcards
Deficient…. usually results in increased susceptibility to infection by pyogenic bacteria
humoral immunity
Deficient…. usually results in increased susceptibility to viruses and other intracellular pathogens
cell mediated immunity
…. are genetic defects that increase susceptibility to infection and are manifested in infancy or early childhood
primary or congenital immunodeficiencies
…..develop as a consequence of malnutrition, disseminated cancer, tx with immunosuppressive drugs or infection of cells of the immune system
secondary or acquired immunodeficiencies
…. are conserved across widely diverse species
Toll- like receptors
Any loss of function mutation affecting a TLR has….
negative consequences for survival
Primary immunodeficiences may affect one or more components of the immune system, including…
T and B lymphocytes
NK cells
phagocytic cells
complemetn proteins
Immunodeficiencies may result from defects in ….. or from defects in effector mechanisms of innate and adaptive immunity
leukocyte maturation or activation
The principal consequence of an immunodeficiency is
an increased susceptibility to infection
In immunodeficiencies, the types of recurring infections can predict…
the type of immunodeficiency
In X-linked Agammaglobulinemia (XLA) all antibody isotypes are…. and circulating…. are usually absent
- very low- not even IgM or IgD
- B cells
In XLA, Pre-B cells are present in …. in the…
reduced numbers
bone marrow
In XLA, tonsils are usually…. and lymph nodes are…. due to absence of….
- very small
- rarely palpable
- germinal centers
In XLAM the thymus architecture is…. as are the…. areas of spleen and lymph nodes
normal
T cell dependent
Most boys afflicated wwith XLA, remain well during the first…. of life by virtue of maternally transmitted…. antibodies. Therefore, they repeatedly acquire infections with extracellular pyogenic organisms such as pneumococci, streptococci, and haemophilus
6-9 months
IgG
XLA is also known as….
Bruton’s agammaglobulinemia
In XLA, … are usually absent and … are present in reduced numbers in the bone marrow
circulating B cells
Pre-B cells
The defect in XLA is associated with a loss of function of…. that is important for Pre-B cell expansion and maturation into Ig-expressing B cells
Bruton Tyrosine Kinase
Bruton Tyrosine Kinase is important for….
pre-B cell expansion and maturation into Ig-expressing B cells
X-linked immunodeficiency with hyper-IgM is characterized by very low serum …,… and…
IgG, IgA, and IgE
X-linked immunodeficiency with hyper-IgM is also characterized by a markedly elevated concentration of….
polyclonal IgM
In contrast to patients with XLA, hyper-IgM patients have …..
lymphoid hyperplasia
The defect in X-linked immunodeficiency with hyper-IgM is a loss of function of…. that is expressed on helper T cells
CD40 (aka CD154)
The loss of CD40 (aka CD154) prevents the T cell from ….
Thus, B cells are not signaled by the T cell to go through…. and only produce…
- co-stimulating antigen-specific B cells (through CD40)
- isotype switching
- IgM
Treatment of humoral immunodeficiencies is….
routine– prophylactic antibiotics or gamma-globulin therapy
There are few if any treatments for…
defects associated with deficient T cell responses so patients with absolute defects in T cell function rarely survive past infancy/childhood
DiGeorge’s syndrome is a developmentally related disease associated with….
tissue morphogenesis– the thymus does not develop
In digeorges syndrome, thymic hypoplasia results from defects in morphogenesis of the….
3rd and 4th pharyngeal pouches during early embryogenesis
In digeorge’s syndrome, the percentage of T cells is variably…. as a result, there is a relative increase in the percentage of ….
decreased
increase
In digeorge’s syndrome, B cell function is impaired only to the extent of needing..
T helper cells
In digeorge’s syndrome, most infants die from…. within first few months or second year of life. Patients who survive infancy are usually…
- seizures, cardiovascular defects, infections
- mentally retarded
There are clinical similarites between digeorge’s syndrome and…
fetal alcohol syndrome
Severe combined immmunodeficiency is a rare, fatal syndrome characterized by
profound deficiencies in T and B cell function
