2. Total blood volume is 4.5-5 litres.
If blood containing anticoagulants (e.g.heparin
, potassium oxalate) is centrifuged , the plasma
separates out as a supernatant while the cells
remain at the bottom.
About 55-60% of blood is plasma
The packed cell volume or hematocrit is about
40-45%
3. Plasma is the clear straw coloured fluid
portion of the blood minus its cellular elements.
It constitutes about 55% of the blood volume.
Serum is plasma minus clotting factors
(fibrinogen & prothrombin ).
The defribrinated plasma is called serum
4. PLASMA contains the following composition:
WATER:
Is the main constituent of Plasma – 91%
SOLIDS: 9% of the plasma (1% inorganic molecules
& 8% organic molecules)
7. Inorganic molecules are sodium, potassium,
calcium, magnesium, chloride, iodide, iron,
phosphates & copper.
Gases presents in the plasma are O2 ,Co2,& N2 .
8. plasma proteins…
- forms 7% of the solids in plasma
- their normal valves – 7.4 gm%
ranges from (6.4 – 8.3 gm%)
INCLUDES:
ALBUMIN
GLOBULINS
FIBRINOGEN
9. Total protein content of normal plasma is
6 - 8 g/100ml
The plasma proteins consist of :
1)albumin (3.5-5 g/dl)
2)globulins (2.5-3.5 g/dl)
3)fibrinogen (200-400 mg/dl)
10. The albumin : globulin ratio is usually between 1.2
:; 1 to 1.5 :1
Almost all plasma proteins , except
immunoglobulins are synthesized in liver
11. In clinical laboratory, separation is usually done by
salts.
Thus , fibrinogen is precipitated by 10% and
globulins by 22% concentration of sodium sulphate
Ammonium sulphate will precipitate :
albumin by full-saturation
globulin by half-saturation
12. In clinical laboratory , total proteins of patients are
estimated by Biuret method.
Albumin is quantitated by Bromo cresol green
(BCG) method , in which the dye is preferentially
bound with albumin , and the colour intensity is
measured colourimetrically.
14. The most common method of analyzing plasma
proteins is by electrophoresis.
The term electrophoresis refers to the movement of
chargeD particles through an electrolyte when
subjected to an electric field
15. In clinical laboratory , cellulose acetate is widely
used as a supporting medium.
Its use permits resolution , after staining , of plasma
proteins into five bands , designated albumin , α1 , α2
, β and γ fractions, respectively
16. The stained strip of cellulose acetate is called
electrophoretogram.
The amounts of these five bands can be
conveniently quantified by use of Densitometric
scanning machines.
Characteristic changes in the amounts of one or
more of these five bands are found in many
diseases.
17.
18. Various abnormalities can be identified in the
electrophoretic pattern
1) CHRONIC INFECTIONS:
The gammaglobulins are increased
19. 2)MULTIPLE MYELOMA :
In para-proteinemias , a sharp spike is noted and is
termed as M-band.
This is due to monoclonal origin of
immunoglobulins
20. PRIMARY IMMUNE DEFICIENCY :
The gamma globulin fraction is reduced
NEPHROTIC SYNDROME :
All proteins except very big molecules are lost
through urine , and α-2-fraction will be very
prominent
21. CIRRHOSIS OF LIVER :
Albumin synthesis by liver is decreased , with
a complementary excess synthesis by globulins
by reticuloendothelial system
22. CHRONIC LYMPHATIC LEUKEMIA:
Gamma globulin fraction is reduced
ALPHA-1-ANTITRYPSIN DEFICIENCY:
The alpha-1 band is thin or even missing
23. Albumin (69 kDa) is the major protein in
human plasma(3.4-4.7 g/dl)
It makes up approximately 60% of the total
plasma protein.
About 40% of albumin is present in the plasma,
and the other 60% is present in the extracellular
space.
24. The liver produces about 12g of albumin per day ,
representing about 25% of total hepatic protein
synthesis
Albumin can come out of vascular compartment. So
albumin is present in CSF and interstitial fluid.
25. 1)COLLOID OSMOTIC PRESSURE OF PLASMA:
The total osmolality of serum is 278-305 mosmol/kg.
This is exerted mainly by salts, which can pass easily
from intravascular to extravascular space.
Therefore, the osmotic pressure exerted by
electrolytes inside and outside the vascular
compartments will cancel each other.
26. But proteins cannot easily escape out of blood
vessels, and therefore , proteins exert the
„effective osmotic pressure‟.
It is about 25mm Hg, and 80% of it is
contributed by albumin.
The maintenance of blood volume is dependent
on this effective osmotic pressure
28. TRANSPORT FUNCTION:
Albumin is the carrier of various hydrophobic
substances in the blood such as:
i)bilirubin & non-esterified fatty acids
ii)drugs (sulpha,aspirin,salicylate,)
iii)hormones(steroid hormones,thyroxine)
iv)metals (calcium,copper,heavy metals)
29. 3)BUFFERING ACTION :
Albumin has maximum buffering capacity
amongst all proteins
It has a total of 16 histidine residues which
contribute to this buffering action.
30. 4)NUTRITIONAL FUNCTION:
All tissue cells can take up albumin by
pinocytosis.
It is then broken down to amino acid level.
So albumin may be considered as the transport
form of essential amino acids from liver to
extrahepatic cells.
32. 2)PROTEIN-BOUND CALCIUM:
Calcium level in blood is lowered in hypo-
albuminemia
Thus , even though total calcium level in blood is
lowered, ionised calcium level may be normal, so
tetany may not occur.
33. 3) THERAPEUTIC USE:
Human albumin is therapeutically useful to treat
burns,hemorrhage and shock.
4)EDEMA:
Hypo-albuminemia will result in tissue edema
Eg: a)malnutrition
b)nephrotic syndrome
c)cirrhosis of liver
d)chronic congestive cardiac failure.
34. CIRRHOSIS OF LIVER:
Synthesis is decreased.
MALNUTRITION:
Availability of amino acids is reduce and so
albumin synthesis is affected.
NEPHROTIC SYNDROME:
Permeability of kidney glomerular membrane is
defective , so that albumin is excreted in large
quantities.
35. PROTEIN LOSING ENTEROPATHY:
Large quantities of albumin is lost from
intestinal tract.
36.
37. ALBUMINURIA:
Presence of albumin in urine is called
albuminuria.
It is always pathological.
Seen in:
a)Nephrotic syndrome(large quantities)
b)Acute nephritis
c)Inflammatory conditions of urinary tract.
Detection of albumin in urine is done by heat and
acetic acid test.
38. MICRO-ALBUMINURIA:
In micro-albuminuria or minimal albuminuria
or plauci-albuminuria , small quantity of
albumin (30-300 mg/dl) is seen in urine
It is estimated by RIA
Increased levels of microalbuminuria is an
indication of early involvement of renal tissue
in diabetic patients
39. Albumin-globulin ratio :
In hypo-albuminemia, there will be a
compensatory increase in globulins which are
synthesized by the reticulo-endothelial
system(plasma cells).
Albumin-globulin ratio (A/G ratio) is thus
altered or even reversed.
40. Hypoproteinemia :
Since albumin is the major protein present in
the blood, any condition causing lowering of
albumin will lead to reduce total proteins in
blood
41. HYPERALBUMINEMIA :
Increased levels of plasma albumin are present
only in acute dehydration and have no clinical
significance
ANALBUMINAEMIA :
Analbuminemia is a rare hereditary abnormality
in which plasma albumin concentration is usually
less than 1.0gm/L
42. Globulins are bigger in size than albumin .
Globulins constitute several fractions. These are:
α1- globulin
α2- globulin
β- globulin
γ- globulin
44. RETINOL BINDING PROTEIN (RBP)
Retinol (vitamin A) is transported in plasma
bound to RBP.
Most retinol RBP in the plasma is reversibely
complexed with transthyretin (thyroxine binding
protein)
α1- FETOPROTEIN (AFP)
This is present in the tissues and plasma of the
fetus
It may play an immunoregulatory role during
pregnancy.
45. α1- PROTEASE INHIBITOR (API) / α1-
ANTITRYPSIN (AAT) :
API is one of the plasma proteins, that inhibits activity of
proteases particularly elastase, which degrades elastin, a
protein that gives elasticity to the lungs
α1-ACID GLYCOPROTEIN (AAG)
AAG also known as orosomucoid, contains a high
percentage of carbohydrate with a large number of sialic
acid residues
It is synthesized by liver parenchymal cells.
46. PROTHROMBIN
It is synthesized by liver with the help of
vitamin K and involved in blood clotting
48. CERULOPLASMIN (FERRO-OXIDASE)
This is a copper containing protein.
It has oxidase activity
Ceruloplasmin is the major transport protein for
copper, an essential trace element.
It is also essential for the regulation of oxiation-
reduction , transport and utilization of iron
Plasma ceruloplasmin level is reduced in Wilson‟s
disease in patients with malnutrition and in the
nephrotic syndrome.
49. TRANSCORTIN /CORTICOSTEROID BINDING
GLOBULIN:
This binds cortisol
It is synthesized in liver and synthesis is increased by
oestrogen
HAPTOGLOBIN:
It plays an important role in the conservation of iron by
preventing its loss in the urine
Haptoglobin binds free Hb to form a complex which is too
large to be filtered by the kidney and thus prevents the
loss of iron in the urine.
50. THYROXINE-BINDING GLOBULIN (TBG)
TBG is synthesized in liver
TBG has a electrophoretic mobility between α1 &
α2 globulins
It transports thyroxine hormone(T3 & T4)
α2 - MACROGLOBULIN(AMG)
This is major α2 - globulin , which is a natural
inhibitor of endopeptidases such as trypsin,
chymotrypsin, plasmin, thrombin .etc.
52. HAEMOPEXIN
Like haptoglobulin, haemopexin also plays an
important role in the conservation of iron by
preventing its loss in urine
TRANSFERRIN
Is synthesized in liver
It transports iron(2 molecules of Fe3+ per molecule
of transferrin) through blood to the sites where
iron is required
53. C-REACTIVE PROTEIN(CRP)
CRP is involved in the body’s response to
inflammations .mainly bacterial..
It is useful in differentiating bacterial from viral
infections because the level of CRP is increased
in bacterial infections only.
54. MICROGLOBULIN
This protein forms part of the human leucocyte
antigen(HLA) system
Plasma levels are increased whenever, there is
malignant lymphoid or myeloid proliferation and
renal failure
55. The acute phase response is a non-specific response
to the stimulus of tissue following trauma, infection
,inflammation, burn, etc
Following trauma etc , the body responds by
initiating a series of mechanisms that lead to rapid
decrease in the concentration of many proteins,eg
Albumin
Prealbumin
Transferrin
These are termed “negative acute phase reactants”
56. An increase in the concentration of several
specific proteins occur some hours after the
injury. These proteins are called the positive
acute phase proteins
57. Definition:
The Igs constitute a heterogenous family of serum
proteins, which either function as antibodies or are
chemically related to antibodies
The immunoglobulins are γ- globulins , called
antibodies. All antibodies are immunoglobulin but
all immunoglobulins may not be antibodies
58. They constitute about 20% of all the plasma
proteins
Igs are produced by plasma cells & to some extent
by lymphocytes
59. Immunoglobulins are glycoproteins made up of
light(L) and heavy(H) polypeptide chains.
All Igs have the same basic structure.
The basic Ig is a “Y” shaped molecule and consist of 4
polypeptide chains:
2 H chains
2 L chains
The 4 chains are linked by disulfide bonds
60. An individual antibody molecule always consists of
identical H chains & identical L chains
L chain may be either of 2 types, kappa(κ) or
lambda(λ) but not both
The heavy chains may be of 5 types and are
designated by greek letter:
Alpha(α)
Gamma(γ)
Delta(δ)
Mu(μ)
Epsilon(ε)
63. Igs are named as per their heavy chain type as IgA ,
IgG , IgD , IgM & IgE
The L and H chains are subdivided into variable and
constant regions
L chain consists of one variable(VL) and one
constant (CL) domain or region
Most H-chains consist of one variable(VH) and 3
constant(CH-1,CH-2 & CH-3) domains
IgG & IgA have 3 CH domains whereas IgM & IgE
have 4
64. Each Ig molecule has hinge region between CH-
1 & CH-2, which allows better fit with the
antigen surface.
The variable regions of both L & H chains have 3
extremely variable amino acid sequences at the
amino terminal end called hypervariable region
Enzyme(papain) digestion splits the Ig molecule
into 2 fragments named as Fab (Fragment for
antigen binding) and Fc (crystallizable
fragment)
65.
66. The primary function of antibodies is to protect
against infectious agents or their products.
Igs provide resistance because they can :
Neutralize toxins & viruses
Opsonize microbes so they are more easily
phagocytosed
Activate complement & prevent the attachment
of microbes to mucosal surfaces
67. In addition to these functions, antibodies can
act as an enzyme to catalyze the synthesis of
ozone (O3) that has microbicidal activity.
68. IgG (HEAVY CHAIN γ ) :
Is a monomeric molecule with 2 antigen binding
sites
There are 4 subclasses, IgG1 to IGg4 based on
antigenic differences in the H-chains and on the
number and location of disulfide bonds
It is produced mainly in the secondary response
and constitutes an important defence against
bacteria & viruses
69. IgG is the major class of immunoglobulin found in
the serum which accounts for 70% of the total
IgG is the only antibody that crosses the placenta
& therefore is the class of maternal antibody that
protects the fetus
Functions:
Neutralizes bacterial toxins and viruses
Opsonises bacteria, making them easier to
phagocytize
Activates complements which enhances bacterial
killing
70.
71.
72. IgA is the 2nd most abundant class constituting
about 20% of serum immunoglobulins
IgA occurs in 2 forms:
Secretory IgA
Serum IgA
Secretory IgA is a dimeric molecule formed by 2
monomer units, joined together at their carboxy
terminals by a protein termed J-chains
73. Additionally secretory IgA has a secretory
component attached to dimer
Secretory IgA is found in external secretions
such as colostrum,saliva,tears and respiratory ,
intestinal & genital tract secretions
Serum IgA exists as monomeric form( found in
internal secretions such as
synovial,amniotic,pleural & CSF )
74. Functions:
Secretory IgA prevents attachment of bacteria
and viruses to mucous membranes and helps
protect mucous surface from antigenic attack
Prevents access of foreign substances to
circulation
75.
76.
77. It is a pentamer consisting of 5 identical Ig
molecules, joined together by disulfide bridges.
IgM accounts for some 10% of normal Ig
IgM is the main Ig produced early in the primary
response
As it is pentamer, it has 10 antigen binding sites &
is the most efficient Ig in agglutination,
complement activation & other antibody
reactions & is important in defence against
bacteria & viruses
78. The natural blood group antibodies, anti-A &
anti-B are IgM
IgM present on the surface of B lymphocytes is
monomer, where it functions as an antigen
binding receptor for antigen recognition
IgM can be produced by fetus in certain
infections.
Functions:
Activate complement, promotes phagocytosis &
causes lysis of antigenic cells(bacteria)
81. It is a monomer and resembles IgG structurally
IgD has no known antibody function but may
function as an antigen receptor
Like, IgM, it is present on the surface of many B
lymphocytes
The circulating concentration of IgD in blood is
very low
IgD is labile
82.
83. IgE is a monomeric molecule similar to IgG. It is
sometimes called reagin
Although IgE is present in trace amounts, in
normal persons with allergic activity have greatly
increased amounts
Functions:
Antiallergic & antiparasitic
84. IgE is responsible for anaphylactic(immediate)
type of hypersensitivity & allergy. Its main
activity is mediated by mast cells or basophils
Defends against worm infections by causing
release of enzymes from eosinophils
Main host defence against parasites like
helminthus, provides protection in the disease
schistomiasis
85. A malignant proliferation of plasma cells
Results in an abnormally high concentration of
serum immunoglobulins, usually IgG or IgA
86. In multiple myeloma, more light chains are
produced than heavy chains and enter the
bloodstream
Because they are of relatively low m.wt, they
pass through glomerular membrane and
appear in the urine, these protein chains of low
m.wt are known as Bence Jones Proteins
87. Bence Jones proteins have the remarkable
characteristic of precipitating on heating urine
from 450 – 600 C and redissolve when the
heating is continued above 800 C
Multiple myeloma with Bence Jones proteins in
the urine is called “light chain disease”