MNSs Flashcards
ISBT — discovered by — in 1927 when —
ISBT 002
Discovered by Landsteiner and Levine in 1927 when immunizing rabbits
composed of how many antigens?
enumerate the most common
MORE THAN 40 ANTIGENS
most common: M, N, S, s, U
T or F: MNSs found on RBCs and some secretions but NOT in tissues
FALSE
found on RBCs and some tissues but NOT in secretions
lectins used for MN typing
anti-M: ?
anti-N: ?
anti-M: Iberis amara
anti-N: Bauhinia variegata and Bauhinia purpura
MNSs genetics
genes are traced at?
chromosome 4q28-q31
MNSs genetics
GYPA gene codes for?
GYPB gene codes for?
GYPA codes for glycophorin A
GYPB codes for glycophorin B
MNSs genetics
GYPA gene considered to be the — with how many exons?
considered to be the ancestral gene with 7 exons
MNSs genetics
how many exons in GYPB gene?
5 exons and one noncoding (pseudoexon)
MNSs genetics
alleles for GYPA and GYPB are codominant. both are —
highly homologous
MNSs antigens are —
fully developed at birth
MNS5 is — antigen
MNS1 is — antigen
MNS2 is — antigen
S antigen is —
s antigen is —
M and N antigen both resides in the — of the —
MNS5: U antigen
MNS1: M antigen
MNS2: N antigen
MNS3: S antigen
MNS4: s antigen
M and N antigen both resides in the glycophorin A of the RBC membrane
MNSs antigens are attached to the glycophorin proteins and these proteins are — and therefore called —
Sialic-acid rich glycoproteins and are called sialoglycoproteins
M and N antigens are at the — of GPA.
GPA and GPB are also expressed in —
at the EXTREME TERMINUS of GPA.
expressed in renal endothelium and epithelium
M antigen is defined by?
there are — copies of GPA per RBC.
Leucine and Glutamic acid
200,000 - 1,000,000 copies of GPA per RBC
N antigen is defined by?
Serine and Glycine
S and s antigens are discovered by? in what year?
Walsh and Carmel Montgomery
1947
the s antigen was discovered in what year?
what is the antithetical partner of S?
1951
s antigen
S and s antigens are found in?
Glycophorin B on RBC membrane
S antigen is defined by?
s antigen is defined by?
there are — copies of GPB per RBC.
S antigen: methionine
s antigen: threonine
there are 50,000 - 250,000 copies of GPB per RBC.
T or F: U antigen is found in glycophorin C on RBC membrane.
FALSE
Glycophorin B
this antigen is considered as the universal antigen. and why it is considered as universal?
U antigen
bcos this was known to be the high incidence antigen
T or F: U antigen is found on RBCs of all individuals except about 5% of Americans.
FALSE.
except about 1% of African Americans (1-35% Africans)
T or F: RBCs with U antigen also carries S and s antigens. then why?
TRUE.
because they both found in glycophorin B on RBC membrane.
U antigen is discovered by? via — in what year?
Weiner via anti-U in 1953
M and N are easily destroyed by what enzymes?
- Ficin
- Papain
- Bromelin
- Trypsin
- Pronase
T or F: S and s resistant to enzymes.
if not, what are the enzymes that could possibly destroy?
FALSE.
they are not resistant but less easily destroyed
Ficin, Papain, Bromelin, Pronase, Chymotrypsin
enzymes can destroy S and s activity but the amount of degradation depend on the?
- strength of the enzyme solution
- length of treatment
- enzyme to cell ratio
these enzymes cannot destroy S and s. enumerate!
- trypsin
- dithiothreitol
- glycine-acid EDTA
what is antithetical?
antithetical is used to describe a pair or more than a pair of antigens that are coded by different alleles of a single gene
frequencies in white and blacks
M+
W: 78%
B: 74%
frequencies in white and blacks
N+
W: 72%
B: 75%
frequencies in white and blacks
S+
W: 55%
B: 31%
frequencies in white and blacks
s+
W: 89%
B: 93%
frequencies in white and blacks
U+
W: 99.90%
B: 99%
anti-M and anti-N are —, rarely natural bcos?
IgM
bcos they are formed due to transfusion or pregnancy
T or F: anti-M and anti-N do not bind complement and causes HDNs and HTRs
FALSE
does not causes HDN and HTRs
what are the similarities of anti-M and anti-N?
they are both:
- cold reactive agglutinins
- reaction is enhanced by acidification
- reacts best at 4C
this antibody can demonstrate dosage. the reaction is enhanced at what pH?
anti-M
pH: 6.5
anti-M is observed from?
common in?
observed from MULTIPAROUS WOMEN
common in children and in patients with bacterial infection
identify what antibody.
some are IgG, less common, and specific at — pH
anti-N
specific at ALKALINE pH
anti-N can demonstrate dosage (reacts better with — than —)
this is observed in?
reacts better with M-N+ than M+N+
renal patients where dialysis machine is sterilized with FORMALIN
anti-S and anti-s, both are — and in —
may exhibit?
both are IgG and in AHG phase
may exhibit dosage effect
anti-S and anti-s reacts at — but some reacts at —
37C but some reacts at 10-22C
if anti-S or anti-s specificity is suspected but the pattern of reactivity is unclear, what will u do?
incubate test at room temp and perform AHG immediately
T or F: anti-S and anti-s does not bind complement and does not cause HDFN and HTR.
FALSE.
- binds complement
- can cause HDFN and HTR with hemoglobinuria
anti-U is an — and is enhanced with enzyme treatment. reacts at?
anti-U causes?
IgG
reacts at 37C and AHG phase
HDFN, HTR, decreased Red cell survival
true or false
some individuals have altered GPA and their antibody is not specific for a portion of the antigen they lack.
this is also referred as?
FALSE.
their antibody is SPECIFIC
reffered as MNSs autoantibodies
