lymphocytes and immunity Flashcards
immunity we are born with and is obtained by WBC phagocytosis, and is present on intact skin, stomach acids, and complement proteins
innate
immunity that occurs due to sensitization which is the resistance to an infection after the first invasion by a specific foreign organism or toxin
acquired
immunity passed down to provide temp immunity from specific antigens
ex: baby gets this from mom
passive
what are antigens
foreign organisms or toxins that the body recognizes as foreign
ex of antigens
carbohydrates, protein, dust, bacteria
where are antigens first phagocytized
by macrophages in lymphoid tissue then the macrophages then pass on the Ag markers (epitopes) to lymphocytes
specific groups of B or T lymphocytes responsive to single type of Ag after sensitization
clones
types of acquired immunity
humoral immunity (B lymphocytes) and Cell-mediated immunity (t lymphocytes)
-b lymphocytes originate in pluripotent stems cells then are preprocessed in the bone marrow and then colonize to lymphoid tissue
-produce antibodies that attack the invading organism
humoral immunity
t lymphocytes originate in pluripotent stem cells then are preprocessed in thymus gland before birth and for a few months after and then lymphoid tissue
-produce activated lymphocytes that destroy foreign invaders
cell-mediated immunity
examples of primary lymphoid tissue
thymus and bone marrow
examples of secondary lymphoid tissues
lymph nodes, spleen, peyer’s path, waldeyer’s ring, lymph nodes, mesenteric lymph nodes
are known as “battle manager” and are activated T lymphocytes
helper T (CD4)
what does Cytotoxic T (CD8) do
destroys antigens directly
is specific for individual antigens
responsible for rejecting transplanted tissues or organs and killing cancer cells
-uses cytotoxic and digestive enzymes
what type of cells are suppressor T cells
regulatory cells
t lymphocytes make up how much percent of lymphocytes
70 %
how much % of activated lymphocytes become memory cells and are preserved in lymphoid tissue as blueprint for battle against specific antigen for lymphocyte
5-10
what are important in stimulating the immune response in T lymphocytes?
lymphokines
what are the most numerous T lymphocytes
CD4 helper T cells
when exposed to antigens, what do helper T cells excrete that stimulate the entire immune system
lymphokines (interferon, interleukins)
what does HIV do the CD4 cells
strikes the key compound in the immune system and causes paralysis in the immune system
suppressor T cells
can suppress helper t and cytotoxic t cells
moderate immune activity
makes sure our immune response does not attack our own cells
B lymphocytes are what % of lymphocytes
30
b lymphocytes action?
with the stimulation of lymphokines or antigen present, can change appearance and begin to divide
plasma cells
are known as antibody factories and produce specific antibodies at a rate of 2,0000/s/cell
memory cells?
stored B cells aimed at specific antigen
how vaccinations work against body and are developed (flu, polio, covid, hepatitis)
igA
involved in secretions such as tears, saliva, and protects against topical and mucus membrane bacteria infection
IgM
formed in blood reaction
foreign RBC antigen
IgE
elevated in asthma or allergies, can mediate anaphylaxis, attaches to mast cells and basophils
when antigens bind together as clumps
agglutination
when antibodies cover toxic sites of antigenic agents
neutralization
mechanisms of action of antibodies
activate complement system that destroys the invader makes up 20% of plasma proteins
what do you call the system that 20 proteins can be activated in multiple ways to destroy the invading antigen or toxins
and amplify the effects of the immune system
complement system
the proteins tend to circulate as inactive enzymes called ___
zymogens
what is self tolerance autoimmunity
immune system can recognize a person’s own tissue as “self”
what is molecular mimicry autoimmunity
a foreign antigen portrays invades the body and pretends to be one of our cells
activated t cells or ab are formed and attack against the invader but also our own cells
ex: type 1 DM , SLE, MS
hypersensitivity reactions are
exaggerated or inappropriate immune response can be local (urticaria) or systemic (anaphylaxis)
antibody mediated: I (IgE triggered and non IgE triggered), II (IgG, IgM, complement-mediated), III (immune complex (Ag-Ab) response): T cell-mediated IV
what are most frequently associated with anaphylaxis
muscle relaxants both depolarizing and non depolarizing
anaphylaxis vs anaphylactoid
igE mediated activation of mast cells and basophils- must have a prior exposure with specific IgE generation
direct activation and degranulation of mast cells and basophils by foreign substance- non IgE, does not need prior exposure (contrast media, opioids, sulfites)
both equally life threatening
how does HIV work
attaches to surface of T cells and other cells and injects RNA into R cells
T cell becomes factory for producing HIV
once helper T cell is taken over by HIV we lose a lot of the immune power in our body
steps of HIV
- release of RNA into T cell
- reverse transcription- HIV RNA converted to HIV DNA
- HIV DNA enters nucleus and incorporated in cell DNA
4 & 5. RNA produced and processed (proteases) for viral assembly
6, newly made HIV released from cell and ready to infect other cells
