Practice test review Flashcards by Nebuchadnezzer II

What is the antigenic determinant region?

It is the epitope of the antigen that binds lymphocyte receptors at the hyper variable region

How well did you know this?

Not at all

Perfectly

Allotype

minor allelic differences in the sequence of Igs between individuals, determined by allotypes of your parents, useful in determining relatedness

-Usually result from substitution of only one or two amino acids in the constant region usually of heavy or light chains

How well did you know this?

Not at all

Perfectly

Isotype

The class of an antibody heavy or light chain, IgM ,IgE IgA are examplesof different isotypes

How well did you know this?

Not at all

Perfectly

Idiotype

unique combining region, made up of the CDR amino acids of its L and H chain, that each antibody has

How well did you know this?

Not at all

Perfectly

Immunogen

a form of antigen that actually produces an immune response.

○ Ie: taking a skin biopsy and putting it on another person. Will react with their immune system, but not yours.

How well did you know this?

Not at all

Perfectly

Normal WBC for:
Neutrophil:
Eosinophil:
Basophil:
Monocyte:
Lymphocyte:

Neutrophil: 40-60%
Eosinophil:1-4%
Basophil: 0.5-1%
Monocyte: 2-8%
Lymphocyte: 20-40%

How well did you know this?

Not at all

Perfectly

Where is B12 absorbed in the body?

terminal ileum

How well did you know this?

Not at all

Perfectly

Where is folate absorbed in the body?

jejunum

How well did you know this?

Not at all

Perfectly

Which thalassemia ALWAYS requires transfusions?

B-thal major (cooleys anemia)

How well did you know this?

Not at all

Perfectly

Would you expect a high or low level of homocysteine in B12 and folate deficiency? Why?

High homocysteine:

homocysteine - cant be converted to methionine or cysteine w/ B12 or folate -> builds up

How well did you know this?

Not at all

Perfectly

Would you expect a high level of methylmalonic acid in folate deficiency? Why?

No. it should be normal.

You are not deficient in B12 -> MA is converted to tetrahydrofolate -> doesnt build up like it would in B12 deficiency

How well did you know this?

Not at all

Perfectly

Is warm antibody-induced autoimmune hemolytic anemia (AIHA) extravascular or intravascular hemolysis? What antibodies are they mediated by?

extravascular, IgG antibodies

How well did you know this?

Not at all

Perfectly

Hemoglobin H contains which chains (how many alpha, beta, ect.)?
-due to what?

4 beta
(tetramer of beta  due to 3 alpha gene deletion)

milder than beta thal*

How well did you know this?

Not at all

Perfectly

Hemoglobin Barts contains which chains (how many alpha, beta, ect.)?
-due to what?

4 gamma chains due to under production of alpha globin

How well did you know this?

Not at all

Perfectly

Is hemolysis associated w/ high or low levels of haptoglobin? Why?

Low levels
rbc lyse -> free hemoglobin binds haptoglobin -> hemoglobin-haptoglobin complex is clears quickly by the liver -> low or undetectable haptoglobin levels.

How well did you know this?

Not at all

Perfectly

Is hemolysis associated w/ high or low levels of LDH? Why?

RBC rupturing->released hb converted to unconjugated bili-> high bili > high LDH

How well did you know this?

Not at all

Perfectly

An increase in what things are going to shift the oxygen dissociation curve LEFT? What does that indicate?

left shift = oxygen is held tighter = favors O2 loading (not unloading)

How well did you know this?

Not at all

Perfectly

An increase in what 3 things are going to shift the oxygen dissociation curve RIGHT? What does that indicate?

Temp, CO2, 2-3, BPG

right shift = oxygen affinity lower = favors O2 unloading

How well did you know this?

Not at all

Perfectly

How do you calculate MCV?

MCV = HCT / RBC

How well did you know this?

Not at all

Perfectly

How do you calculate HCT?

HCT = RBC x MCV
or
HCT ~ 3x Hb

How well did you know this?

Not at all

Perfectly

How do you calculate MCH?

MCH = HGB / RBC

How well did you know this?

Not at all

Perfectly

What is marrow cellularity?

how do you calculate it?

how much of marrow is hematopoietically active?

Should be 100 - Age:
ie 75% cellularity for 25 year old.

How well did you know this?

Not at all

Perfectly

What test do you use for hereditary spherocytosis? Why?

osmotic fragility test

spherocytes lyse at a higher osmolarity than RBC’s

How well did you know this?

Not at all

Perfectly

High levels of neutrophils can be due to what 2 things?

neoplastic (CML)

reactive (leukemoid rxn secondary to disease)

How well did you know this?

Not at all

Perfectly

What is normal Absolute neutrophil count (ANC)?

>1500 | or 1500-8000/mm3 or 1.5-8.0

Within one immunoglobulin molecule there might be 2 types of light chain. T or F?

False

Allotypic exclusion

single B cell can synthesize only 1 H chain (maternal or paternal in origin) and only 1 L chain (maternal or paternal, kappa or lambda)

Why are protein and killed vaccines given early; live virus vaccines after a year.

protein Ags work in newborns so give them early live viruses (which have to grow in the vaccine before they achieve an immunogenic dose) have to wait until there is no residual maternal Ab.

The primary cell type in a germinal center in a lymph node follicle in the cortex is?

B cell. Thats why the tfh migrate into the follicles of the cortex. Where B cells are abundant

How many polypeptide chains does IgA have? Explain

10 polypeptide chains: 4 light, 4 alpha (heavy) chains, 1 Joining chain and 1 Secretory component

How many polypeptide chains does IgG have? Explain

4 2 light and 2 gamma (heavy) chains

How many polypeptide chains does IgE have? Explain

4 2 light and 2 epsilon (heavy) chains

How many polypeptide chains does IgD have? Explain

4 2 light and 2 delta (heavy) chains

How many polypeptide chains does IgM have? Explain

21 10 light, 10 mu and 1 joining chain

Valence refers to the number of antigenic determinants an antibodymolecule can theoretically bind. What is the valence of IgG? of secreted IgA? of IgM? of Fab? of F(ab2)?

count the dual tips* ``` IgG - 2 secretory IgA - 4 IgM - 10 Fab - 1 Fab2 - 2 ```

The part of antibody molecules that contacts the antigenic determinant

the hypervariable region of antibody (light/heavy chain)

Can immunogens always be considered antigens?

Yes, bc they actually produce immune response, but not all antigens are considered an antigen for someone else

Fab can bind what?

1 fab binds 1 antigen. 2 fabs binds 2 antigens but no agglutination will be seen.

Do T cell mediated immunity involve plasma cells? Why or why not?

No. T cells will interact w/ B cells, which then go on to differentiate into plasma cells.

Fc of IgE adheres to which cells? What happens?

Mast cells and basophils -> trigger histamine release -> immediate hypersensitivy/allergy

Somatic hypermutation

Recombined V(D)J unit is "hypermutable" Each time B cell divides (after antigenic stimulation, so somatic): good chance that 1 of daughters will make slightly diff. antibody -not T cells!

Which complement is opsonizing for polymorphonuclear neutrophils (PMNs) ?

C3b so that means that the PMNs will have a firm grip on the antigen if it is opsonized w/ c3b

Which complements are lytic for polymorphonuclear neutrophils (PMNs) ?

○ Membrane attack complex (MAC) is activated when C5 activates C6-C7-C8-C9. ○ C8 and C9 form a lesion on the target cell membrane (looks like a hole)

Which complements are anaphylatoxic for polymorphonuclear neutrophils (PMNs) ?

C3a, C4a and C5a can all release histamine from mast cells or basophils

Which complements are chemotactic for polymorphonuclear neutrophils (PMNs) ?

C5a *hallmark

myeloid

arises from cell type in marrow (everything that isnt lymphoid)

% of myeloid cell types in WBC % lymphoid

1. Neutrophils 60% 2. Monocytes 5% 3. Eosinophils <1% 5. lymphocyte 20-40%

Which part of the membrane attack complex polymerizes in the membrane to form a transmembrane channel?

A single B cell switches from making IgM anti-measles to IgG anti-measles. Are the heavy or light chains changed during this switch?

Heavy chains are changed during the switch. | mu, delta, gamma, epsilon, alpha

Can IgG neutralize viruses? Can it be actively transported into external secretions such as saliva?

yes - neutralize virus no - saliva

Central lymphoid organs - in humans - in birds

hu: BM and thymus birds: bursa of fabricius

Can you make antibodies to something that isnt a protein?

yes

Clonal deletion

is a process by which B cells and T cells are deactivated after they have expressed receptors for self-antigens and before they develop into fully immunocompetent lymphocytes

Is it possible to see surface IgD, surface IgM, surface Class I MHC, and surface Class II MHC—all on the same cells?

yes - perfectly normal

F + S, no A | indicative of what?

Sickle cell anemia or | HbS β-thalassemia

F + A + Bart’s | indicative of what?

Hb H disease

Spectrin defect = high or low reticulocyte index? MCV??

``` high reticulocyte low MCV (along w/ hgb and hct) ```

How do you calculate ANC?

total WBC x neutrophil % | Check units!

The majority of iron in the body is normally contained in:

Hemoglobin

Which form of anemias will lead to hypersegmented neutrophils?

B12 and folate deficiency (pancytopenia)

B12 is required for the function of which two different enzymes?

1. methylmalonyl-CoA mutase, -which converts methylmalonyl CoA --> succinyl CoA 2. methionine synthase, - which converts homocysteine and 5-methyl-tetrahydrofolate --> methionine and tetrahydrofolate

B12 affects function of 2 enzymes. What products will build up if there is a B12 deficiency?

B12 deficiency will lead to increased levels of both: 1. serum methylmalonic acid 2. plasma homocysteine

Folate is required for the function of which enzyme?

methionine synthase, | - which converts homocysteine and 5-methyl-tetrahydrofolate --> methionine and tetrahydrofolate

Folate affects function of 1 specific enzymes. What products will build up if there is a folate deficiency?

plasma homocysteine (methionine synthase, - which converts homocysteine and 5-methyl-tetrahydrofolate --> methionine and tetrahydrofolate)

You are presenting your patient with anemia to your attending on morning rounds, and she asks you if the patient has hypochromia. To answer her question, you tell her the patient’s: (what cbc value?)

MCH: which tells you the average amount of hemoglobin per RBC.

cold AIHAs are mediated by what? how is this different from warm?

activation of complement Warm AIHAs are mediated by IgG

What are the cells in the bone marrow from which platelets are derived.

Megakaryocytes

what are the chains found in HbA2? HbF?

HbA2? two alpha and two delta chains (α2δ2) HbF? two alpha and two gamma chains α2γ2

Would you have increased or decreased plasma haptoglobin in hemolysis? Why?

The hemoglobin-haptoglobin complex is cleared quickly by the liver, leading to low or undetectable haptoglobin levels

erythrocytosis

increase in the number of circulating RBC, (increased hematocrit)

If you lack a 2,3-BPG binding site, describe how a pt. becomes plethoric

Hb higher O2 affinity → ↓ O2 tissue delivery → erythrocytosis (elevated RBC) →increased erythropoiesis → increased red cell count, plethoric (red-appearing)

Is acute renal failure or splenic sequestration a common manifestation in acute sickle cell anemia ?

Splenic sequestration. renal failure is more chronic than acute