Medical Director and Managing Trustee Rotary/TTK Blood Bank .. This book of 26 chapters is designed to share current topics in blood banking, transfusion. About this book. Transfusion Medicine offers a Autologous Blood Donation and Transfusion (Pages: ) · Summary · PDF · References. Overall, this book talks a lot about blood transfusion, blood group antigens, immune system, Download [PDF] Textbook Of Blood Banking And Transfusion .
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PDF Drive is your search engine for PDF files. As of today we have 78,, eBooks for you to download for free. No annoying ads, no download limits, enjoy . PDF | 5 minutes read | Blood Banking practices | ResearchGate, the conferences in India and published several books on the subject. . Emory University Hospital Blood Bank, the blood and tissue banks of leading to the publication of more than 75 papers and numerous book chapters and.
The unexpected alloantibodies are usually red cells immune and formed by exposure to red cells due to blood transfusion or pregnancy. A or B antigens may be weakened in patients with leukaemia. The activated complement complex is indicated by the bar above the letters and numbers. Stopper lubes and store at 4"C. After this Clqrs and immunoglobulin are no longer needed. To ensure adequate and separate budget for blood transfusion services. The figure may vary from units per bed per year.
Skip to Main Content. Transfusion Medicine , Third Edition Author s: Jeffrey McCullough MD,. First published: Print ISBN: About this book Transfusion Medicine offers a concise, clinically focused and practical approach to this important area of medicine. This third edition includes updated information on a number of areas including: Current debate on clinical effects of stored red blood cells Emerging infectious diseases and impact on blood safety New concepts of massive transfusion World blood supply Platelet transfusion Pathogen inactivation Transfusion Medicine will be valuable to all those working in the field of blood banking and transfusion.
Free Access. Summary PDF Request permissions. Tools Get online access For authors. Email or Customer ID. Forgot password? Old Password. Carpeted or difficult-to-clean surfaces can be protected with a clean suitable overlay. Donation Premises It should be attractive. Refreshment service areas should be separated from areas of blood collection and storage. Currently CPDA-1 anticoagulant solution is mostly used.
Calcium gluconate. Rh D group are written on the label of bag for blood collection. If less blood is to be collected. Oxygen cylinder with regulator and mask. Anticoagulant Solution. Dexamethasone sodium phosphate. It should be sterile. If less amount of blood is to be drawn two factors must be calculated: Aromatic spirit of ammonia. A physician should be present on the premises when blood is being collected. Intravenous crystalloid normal saline sodium chloride 0.
The dates of collection and expiry. Identification Blood bag and pilot tube s are identified by a donation number at the time of collection of blood. Choose the site of venipuncture in the anticubital area of the arm. Place the bag on a balance and ensure that it is below the level of the arm. The anticoagulant solution must be clear.
Release the blood pressure cuff and thoroughly clean the proposed site of venipuncture with an antiseptic lotion in the following way: Asking the donor to close the fist usually helps in bringing the vein into prominence. Allow it to dry. Donors Selection and Blood Collection 1 How much blood can be safely drawn from the donor. Check the donor name. For example. Inspect the bag for leakage or any other defect.
The calculations when less amount of blood is to be drawn in a bag for ml blood: Apply blood pressure cuff. Donation number on the bag and form should be same. Ask the donor to close the fist.
Invert bag several times to mix blood thoroughly. Then the donor is allowed to sit up and go for refreshment. If platelets are to be harvested. Uncover the sterile needle and perform venipuncture immediately. The initial weight of the bag and the anticoagulant solution should be taken into account while measuring the total weight. Deflate the cuff or release the tourniquet. As soon as the required amount of blood is collected.
The donor should be under constant observation throughout the phlebotomy and should never be left unattended. Ask the donor to open and close hand or to squeeze a rubber ball. The donor should remain on the bleeding couch for minutes under the observation of the staff. Repeat the process a second time.
Strip blood bag tubing. Check the arm and apply band-aid after bleeding stops. The flow of blood should be uninterrupted and constant. Seal the tubing attached to the bag into segments with di-electrictube sealer. Place the sterile swab at the venipuncture site. Mix the blood and anticoagulant gently and periodically during collection of blood. Remove blood pressure cuff or tourniquet. Seal the tube with di-electric tube sealer and separate the needle.
Ask the donor to put the fingers of the other hand on the swab at the venipuncture site and to raise the arm. Take the bag to the processing table. One ml of blood weighs 1. Inflate blood pressure cuff to maintain pressure mm of Hg.
Do it quickly. Platelets should be separated within hours after the collection of the whole blood. Donor adverse reactions are: Syncope fainting or vasovagal syndrome: The symptoms may include sweating. Nausea and vomiting. Tetany Twitching or Muscular spasm Anxiety and deep breathing may cause the excited donor to loose excess of carbon dioxide.
Personnel in the phlebotomy area must be trained and prepared to respond quickly to those reactions. Put the sterile swab at the venipumcture site and apply pressure with thumb.
Management The donor is asked to breath into a paper bag which brings prompt relief. Donors Selection and Blood Collection The donor should be given donation card and thanked for the contribution and encouraged to donate again.
In general. The skin is usually cold. If there is feeling of faintness or dizziness. Instructions to Donors after donation 1. Number of donation on the blood bag. Drink more fluids than usual in the next 4 hours. Do not remain hungry. Ask the donor to open the fist and withdraw the needle from the vein.
Convulsions True convulsions are rare Management In case they occur: If there is bleeding from phlebotomy site. If symptoms persist. If donor vomits. Cardiac problems Serious cardiac problems are extremely rare in the blood donor. Do not smoke for half an hour. If the donor is in cardiac arrest.
Hematoma Management a Deflate the blood pressure cuff. Do not take alcoholic drinks for at least 6 hours. Rh D negative units must be tested for weak Rh D i. Blood must not be released for use until the discrepancies. As there is no appropriate test which can be done easily in screening blood donor for malaria.
Donor blood should be tested for unexpected antibodies by saline. Donors Selection and Blood Collection 2. Routine testing for other antigens of Rh system is not recommended. Du by anti-human globulin AHG serum. ABO group is determined by testing the red cells with anti-A. Floculation test. Tests using monoclonal antibodies for detection of malarial antigens are available but they are costly.
Test with anti-AB serum is optional if monoclonal anti-A and anti-B are used. B and O cells. Tests for blood transmissible diseases: Rh group must be tested for Rh D only with anti-D serum. In Gibson et al developed an improved preservative of citrate-phosphate-dextrose CPD. The next important development occurred in during the Second World War when acidified citrate dextrose ACD solution was introduced for clinical use by Loutit and Mollison.
The addition of adenine improved the synthesis of adenosine triphosphate ATP in the stored blood. It consisted of a citrate-glucose solution in which blood from rabbits was stored for two weeks. In citrate-phosphate-dextrose with adenine CPDA-1 preservative was developed. Whole blood collected in CPD has a pH 7. Giycosis results in the production of lactate.
The loss of red cells viability is correlated with the "lesion of storage" due to various biochemical changes: Preservative solutions provide buffering capability to minimize pH changes and optimize the storage period. Loss of ATP causes increase in cellular rigidity and decrease in red cell membrane integrity and deformability.
Temperature The lower temperature keeps the rate of glycolysis at lower limit and minimizes the proliferation of bacteria that might have entered the blood unit during venipuncture or from atmosphere. The degree of reduction of 2. Adenine nephrotoxicity due to its unmetabolized product.
Myocardial functions improve following transfusion of blood with high 2. Thus 2. Adenine Simon showed that in CPD solution supplemented with 17 mg 0. Decline of 2. The acid-base status of the recipient. In patients with shock the transfusion of DPG-depleted red cells makes a significant difference in recovery.
The pathological effects of the transfusion of red cells with low 2. After transfusion. This amount is present in 30 units of fresh CPD adenine 0.
DPG-depleted red cells have impaired capacity to deliver oxygen to the tissues. Adenine synthesizes ATP and its level is The additive solution should be added to red cells within 72 hours since phlebotomy.
Red cell concentrates relatively void of plasma are more viscous and difficult to infuse in emergency situations. This allows adequate plasma to remain for red cells nourishment and to improve flow properties.
With the advent of component therapy use of red cells increased. This new blood collection system has a primary bag containing a standard anticoagulant CPD and a satellite bag containing an additive solution. This results in lower plasma yields. This resulted in several problems in preservation. After the plasma is removed from the whole blood into another empty satellite bag. Blood is collected in the primary bag containing anticoagulant solution. Table 3. There is no restriction on the use of additive solutions in any other type of transfusion recipients.
This facilitates better inventory control of blood as well as wider use in pre-deposit autologous donations.
The additive solutions do not increase 2. Preservation and Storage of Blood Table 3. In addition. Dose of heparin for anticoagulation is 0. Additive solution having mannitol are not routinely used for exchange or neonatal transfusion. The cells are rapidly frozen and stored in a freezer.
Glycerol is used most commonly and is added to the red cells slowly with vigorous shaking so that glycerol permeates into the red cells. One of the factors is also the plastic material used for the bags. The plastic material should be sufficiently permeable to CO2 in order to maintain higher pH during storage.
These solutions can be added at any time between 3 days post collection and 3 days after expiration of red cells. The accumulation of excessive amount of acid due to glycosis even at low storage temperature is also a major problem in liquid preservation of red cells.
The rejuvenated red cells are either washed with saline 2 Litres of unbuffered 0. Earlier heparinized blood was used in open heart surgery but now usually it is not used as extracorporeal pumps are now usually primed with crystalloids and not with blood.
For freezing red cells a cryoprotective agent is added to red cells that are less than 6 days old. It is known that DEHP leaches from plastic into plasma and cell membrane during storage and may be harmful to the patient. Plastic Bags Many other factors may limit the viability of transfused red cells. The freezing and storage temperature depends on the concentration of glycerol. Glycerol which permeates red cells fairly rapidly during freezing is most effective in protecting the human red cells.
Frozen red cells are primarily used for autologous transfusion and the storage of rare group blood. MA is commercially available. The rejuvenation process is expensive and time consuming and is rarely used.
Rejuvenate Solutions Rejuvenate solutions having phosphate. Red blood cells rejuvenation solution. If glycerol cryoprotective agent is added to the cells they can be frozen and thawed without damage Polge et al. Currently the blood is stored in plastic bags made of polyvinyl chloride PVC with plasticizer. So there is need to develop improved plastic blood bags as well as preservative solutions.
Cytosol Laboratories. Two concentrations are used to freeze red cells. Effect of Freezing It is believed that freezing damages red cells due to the intracellular ice formation and probably to some extent due to hypertonicity. The effect of the glycerol is probably due to the fact that it limits ice formation and provides liquid phase in which salts are distributed.
The effect of heparin can be neutralized with protamine sulphate. The solution is added directly to the red cells. Removal of glycerol is achieved by systematically replacing the cryoprotectant with decreasing concentrations of saline. Commercially available Cell Washing System manufactured by several companies can be used.
The frozen red cells can be stored for 10 years. Appropriate volume of 6.
Red cells stored in additive solutions can be frozen up to 42 days. Method of freezing and preservation of red cells in frozen state: The glycerolizing solution consists of 6. First ml of glycerolizing solution is added to the cells in the collecting bag with vigorous shaking.
The bag is centrifuged. Most blood banks use the high glycerol technique. After at least two minutes of equilibration. Shelf-life of the processed unit is 24 h. The washed cells are finally suspended in isotonic glucose saline and ready for transfusion. Subsequently followed by washing with solution progressively less hypertonic and finally with isotonic electrolyte solution containing glucose. Then wash with one to two litres of 1. Protocols for each instrument should be followed as advised by the manufacturers.
Virtually all plasma. This allows the glycerol to begin diffusing out of the red cells while the intracellular environment remains hypertonic. Low glycerol solution equal in volume to the red cells e.
The intracellular environment of glycerolized cells is hypertonic relative to plasma and the first solution used for deglycerolization must be also somewhat hypertonic. In vivo survival and functions of red cells are comparable to fresh drawn liquid stored red cells because 2. Plasma is taken off and freezed. The shelf-life of the processed unit is 24h.
Deglycerolized red cells consist of red cells in electrolyte solution. Clinical consideration 1. The washing can be carried out either by continuous flow washing in the Haemonetic Blood Processor or by continuous flow washing in Fenwal Elutramatic system or serial centrifugation in the IBM blood processor. Whole blood in CPD is centrifuged at x g for seven minutes. The washed cells are finally suspended in isotonic glucose solution and ready for transfusion.
The pack is centrifuged at X g for 7 min and the plasma is removed. Seal one end by folding. Seal both ends by folding and clamp with paper clip. Tubes should be placed in a metal rack for faster freezing. Preservation and Storage of Blood Indications for the use of frozen red cells 1 Freezing of rare blood groups enables long-term storage and supply on a regional and national basis.
Procedure for thawing and deglycerolization: Cells in 4 dialysing tubings can be immersed in the same beaker for dialysing. Transfer cells from tubing to labelled tubes. They do not need agitation. Add an equal volume of AB serum to packed cells.
Plastic Bag Maintenance of pH and function of platelets depend on the permeability of the storage bag to oxygen and carbon dioxide. Stopper lubes and store at 4"C. Post transfusion recovery of granulocytes in circulation and migration into inflammatory loci is better if transfused with in 8 hours of storage than that if granulocytes stored for 24 hours.
They should also have alarm systems with audible signals. No food should be stored in the refrigerators and freezers.
These frozen products are fragile. These facilities should have battery back up. Ice should not come in direct contact with blood at any time because it can cause hemolysis of the red cells or blood. All storage equipment. Dry ice should be kept at the bottom and at the top inside the wellinsulated container.
Dry ice is used to maintain the frozen state. In climates that are extremely warm or where the shipment journey will be lengthy. Shipping of Platelets Shipping of stored platelets to the transfusion facility should use a well-insulated container. Physical storage conditions best suited for products maximum survival are also important. Freshly drawn blood. Temperature recording charts should be changed regularly. Ice should be put at the top inside the container so that the cool moves down through the shipping box.
Wet ice is a good refrigerant for red cell shipment. Red Cells Washed R. Units are inspected for hemolysis. AS additive. CPDA-1 whole blood with plasma removed.
Frozen at. Abnormal units should not be issued and the cause should The blood should be inspected to check for possible bacterial contamination. Final volume. Plasma with a green hue need not to be rejected because this is caused by exposure of bilirubin pigments to the light.
Prior to issue plasma in both the main bag and segments should be visually inspected for hemolysis or discolouration. In case of hemolysed blood the colour of blood both in bag and tubing is changed to purple. This metabolic activity in the unit is not duplicated in the sealed segments. This causes change of colour in the unit but not the colour of the segment. Yercinia enterocolitica. When the segments of the contaminated units are cultured.
Preservation and Storage of Blood be investigated. These abnormal cells may be malignant cells. Pluripotential cells. Off-springs of these stem cells. First it provides the immune mechanism which protects the body against external foreign substances. Contribution to immunology comes from both the basic sciences biochemistry. Role of Immune System The immune system plays two important roles in the human body. They may be similar in appearance but they can be distinguished by the presence of distinctive cell markers.
Cells or micro-organisms to which complement is attached can be removed by phagocytic macrophages. Monocytes in tissue differentiate into tissue macrophages. Macrophages express both class 1 HLA -A. Precursor cells leave bone marrow and travel to thymus gland where they devel P and are released into the circulation as mature T-cells.
These cells are susceptible to C3b receptor on macrophages and they are removed by the macrophages. T Lymphocytes T-Cells T lymphocytes originate from lymphopoietic stem cells in the bone marrow. T-cells Class 11 antigens which are important for transplantation immunity. The macrophages participate in phagocytosis. A second group of cell surface protein found on macrophages are those of major histocompatibility. B-cells and Null cells. In this way many kinds of abnormal cells.
About 75 to 80in the blood are T-cells. An important cell surface receptor on macrophages is the receptor for the Fc portion of immunoglobulin. Some blood group antibodies are capable of complement activation.
Cells coated with antibody can attach to macrophages when the Fc portion of immunoglobulin comes in contact with the Fc receptor on macrophage.
Different types of receptors and histocompatibility antigens are present on the surface of macrophages and they are important in blood banking. Tissue macrophages also possess receptor for C3b component of complement. Null Cells Some lymphocytes that do not carry T or B cells markers are found in blood and are called natural killer NK cells. CD8 cells have suppressive or cytotoxic effects and are called suppressor T-cells.
Upon continued stimulation. CD8 markers interact with MHC class 1 molecules. These cells have the capacity to lyse or destroy a wide variety of infected cells and tumor cells without any apparent antigenic stimulus. B-cells frequently change the expression of its heavy chain. If B-cells are triggered they undergo a process called clonal expansion producing one kind of antibody and the proliferation of that particular cell line.
The helper T-cells: T-cells participate in the regularization of humoral antibody response and cellular response.
The majority of activated B-cells differentiate into IgM-secreting plasma cells. This usually involves an IgM-to-IgG switch. B-cells are precursors of antibody producing plasma cells. CD8 ratio. B-cells are the most important cells of the humoral immune system. Each B-cell expresses only one type of surface immunoglobulin and when triggered produce only one type of antibody. Many proteins on T-cells are identified by monoclonal antibodies.
These helper T. The different kinds of T-cells are named according to their respective function: B Lymphocytes B-Cells B lymphocytes derive from lymphopoietic stem cells and develop in bone marrow in humans. CD4 cells enhance and promote the action of other immune cells and are called helper T-cells.
In acquired immunodeficiency syndrome AIDS. Many surface proteins have been recognized on B-cells and are grouped into three categories: Out of these antigens. Like T-cells. Principles of Immunohcmatology circulate from the blood to lymphatic organs and return to blood stream via lymphatic ducts.
B-cells circulate from the blood to lymphatic organs and return to blood stream via lymphatic ducts. CD4 markers recognize antigen together with maximum histocompatibility complex MHC class 11 molecules. This also results in the generation of memory B-cells with IgG surface immunoglobulin and the secondary antibody response results in the production of IgG antibody.
Biochemical defenses are also present in other parts of the body. Cytokins produced by activated T-cells are important for many phases of B-cells response. This mechanism consists of physical and biochemical barriers that prevent the entry of pathogens into the body. If an organism penetrates epithelial surface.
Biochemical defenses that inhibit or destroy bacterial growth are lactic acid and fatty acid in sweat. Antibody has the capability of reacting with the specific antigen responsible for its production. The acquired immunity is specific and the antibody recognizes to the antigen which initialized its production. Mostly antigens that stimulate this response are T-dependent antigens. First line of this defense mechanism is always present since birth and protect the individual from foreign invaders and does not change on repeated exposures to the same antigen.
The exterior of the human body skin and mucous membranes are impermeable to most infections. Other cytotoxic cells involved in cell mediated immune response are null cells NK. Many body secretions like tears.. B-cells and T-cells. The acquired immunity has memory. Non-self or foreign material initiates adaptive changes that result in either production of antibodies called humoral response or cell mediated response Cellular Immunity Cell mediated immunity or cellular immunity.
In general antibody produced by T-independent antigen is IgM. Humoral Immunity Humoral immunity is mediated by antibodies produced by Lymphocytes B-cells.
These NK cells are able to attack the target cells and kill them. Adaptive Immunity Adaptive immunity has the ability of specificity. T-cells and macrophages play major role in cell mediated immunity. Antibody production involves two type of cells-macrophages.
Cell mediated cytotoxicity is important in lysis of virus infected cells and rejection of allo-graft and tumor cells. Cytokins are divided into lymphokines. Three endogenous pyrogens have been recognized: All these factors directly stimulate the synthesis of prostaglandin in the hypothalamus. These memory cells contribute to the immune response on second or subsequent exposure to the same antigen. A variety of lymphokins are secreted by a number of different types of cells: Cytokines modulate the host response to antigens by regulating growth.
In addition to immune responses. IL-1 is released from donor leucocytes and causes fever. In the secondary immune response.
With in weeks IgM antibodies level decline and IgG antibodies are formed. During this latency period. The earliest antibodies are IgM. Laboratory animals. The clonal line produces a single antibody.
The antibody-secreting clones may then be propagated in tissue culture or by inoculation into mice. All antibody molecules produced by a clone of hybridoma cells are identical in terms of antibody structure and antigen specificity. W to act as antigens. Once one antibody-secreting clone of cells has been established. After suitable immune response. IgM antibodies. Antibody class: Two classes of antibodies are made in the primary immune response.
T-cells and B-cells response is occurring and memory cells are formed. They generally fail to act as antigens and produce no antibody unless coupled to a carrier protein of a size approximately more than The secondary response becomes apparent more rapidly. The resulting hybridomas are screened for antibody with the required specificity and affinity.
As this role has expanded. Substances below An antibody may react strongly with red cells of an individual who is homozygous for the corresponding antigen but react weakly or not at all with red cells of an individual who is heterozygous for an antigen.
IgG molecules are capable of causing the agglutination of red cells if the corresponding antigen is on or protruding from the cell membrane but may not agglutinate when corresponding antigen is buried within the cell membrane. Blood Groups Genetics The blood group antigens are the products of specific genes. A gene may be recessive gene. The action of the gene causes the production of an enzyme which in turn causes the addition of another sugar to the basic precursor substance.
Red cells antigens are present not only on red cells but some have also been detected on leucocytes. Changes in blood group antigens have also been noted during pregnancy e. An individual who is homozygous for a particular gene will have antigen product of the respective gene in double dose homozygous and an individual who is heterozygous for a gene will have antigen product of respective genes in single dose heterozygous.
The specificity of the blood group antigens has been shown to be determined by the sequential addition of sugar residues to a common precursor substance as a result of gene action. If both the inherited genes are dominant. Each gene occupies a specific position locus on the DNA of the chromosome. Principles of Immunohematology On the surface of red cells are minute glycoproteins and glycolipids. Antigens of some specificities are confined wholly on the red cell membrane e. Some antigens are poorly developed at birth e.
A or B antigens may be weakened in patients with leukaemia. The number of antigen sites on the red cells varies according to specificity. The precursor substance. Rh antigens. These substances are of sufficiently high molecular weight to act as antigens and are known as blood group antigens. The antigens on the red cells are not always constant throughout life. Thus there are approximately lmillion ABO antigen sites and The particular locus may be occupied by one or more different forms of the gene.
Acquired B antigen in A. M and N. A gene may be a dominant gene. When these allelic genes on a pair of chromosomes are identical i. There are two types of precursor substances known as Type 1 and Type 2 which differ in terminal linkage See Figs. Some can be altered in certain disease states e. D-galactose 2 molecules.
The antigens on the red cells may be on. All antibodies have two main features in common. This may occur as a result of blood transfusion therapy or feto-maternal blood group incompatibility in pregnancy.
Blood group antibodies IgM. These are called The basic structure of the molecule The function of the molecule i. IgG or IgA are significant in blood banking and they are dealt in detail. Certain blood group genes appear to produce no product even when present in a homozygous state.
A and B. Production of antibodies The introduction of red cell antigen into the circulation of an individual lacking that antigen may stimulate the production of a corresponding antibody. The terms phenotype refers to the detectable products antigens demonstrated through direct testing only. IgD and IgE. There are five different forms of blood group antibodies IgM. Genotype and Phenotype The term genotype refers to the sum total of genes present on the chromosomes regardless of whether or not they produce detectable products.
The genotype is determined through direct testing of gene products antigens and family study. Only two types of light L chains Kappa and Lambda are found in all classes of immunoglobulins and two light chains of any Ig are identical being either Kappa or Lambda.
The immunoglobulins are named according to the structure of heavy H chains. Fig 4. The structure of the immunoglobulin molecules. Individuals do not generally produce antibodies when red cells possess the corresponding antigen. The heavy chain has a coiled hinge region that gives the molecule flexibility and it is in this region that enzymes or albumin act. The five types of heavy chains are designated as alpha lgA. MN and P blood group systems. The common occurrence of naturally occuring antibodies suggests that their antigens are widely found in nature.
Principles of Immunohematology incomplete or acquired antibodies IgG. The rest of the light and heavy chains represent regions with constant amino acid sequence. The co-valent are mainly in the hinge region. Certain antibodies occur without known antigenic stimulus.
Kidd and Ss blood group system. Common naturally occurring antibodies react with the ABO. Mostly they are IgM cold agglutinins. The first amino acids of both heavy and light chains have a variable sequence and form variable region.
Common immune antibodies react with Rh. These are known as complete or natural antibodies lgM. Heavy H polypeptide chains are joined by covalent disulphide and non-covalent bonds to each other and to a pair identical light L chain. These are IgG 1. Biological activities other than antigen binding reactions are the responsibility of the constant portion of the heavy chains.
Antigen binding sites are believed to be located at the end of heavy and light chains in the variable region of the Ig molecule. Each Fb fragment is composed of one light chain and half of one heavy chain bound by covalent disulphide bonds.
There are four sub-classes of IgG known on the basis of structural and morphological differences. More details are beyond the scope of this book. IgG in plasma have half-life of 23 days. See Fig IgG immuno-globulin can transfer from mother to fetus causing hemolytic disease of newborn. Functions of various parts of lg molecules.
One crystallizable Fc fragment and two identical Fb fragments. The change in shape is facilitated at the hinge region. IgM is more effective than IgG in activating complement. See Fig4. IgG immunoglobulins are antibodies to Rh. In spite of this limitation. IgG3 and IgG4. IgM Immunoglobulin The 1 gM molecule is made up of five basic structural units in a circular arrangement known as pentamer.
It has additional disulphide bonds linking the Fc portions of alternate heavy chains so as to produce a molecule with central circular portion and five radiating arms like a five-legged spider. Free IgG is usually Yshaped but it is capable of changing its shape to combine with antigen or for other functions i. IgM are potent agglutinating antibodies and activate compliments. The typical pentamer IgM molecule has 10 antigen-antibody sites.
These antibodies are detected by serological tests based on their characteristics. Enzyme papain splits the immunoglobulin at the hinge region into three fragments. The Fc fragment is composed of two halves of two heavy chains bound by co-valent bonds and it is responsible for complement fixation.
This treatment destroys both hemolyzing and agglutinating activities of IgM antibodies and IgG antibodies can be identified in a mixture of IgM and IgG antibodies. Immunoglobulin IgE Immunoglobulins IgE are normally monomoric and are found in a very low concentration in serum or plasma and has the shortest half-life span.
IgM does not cross the human placenta. Transfusion of even few milliliters of blood or its products having IgA may cause anaphylactic reaction in patients having anti-IgA. No blood group antibodies have been reported to belong to this class.
If both IgM and IgG antibodies are present in any serum. Although IgA has no bactericidal effect. IgA immunoglobulin is important in immunohematology. Sometimes anti-IgA are formed following transfusion of plasma products in patients who have no IgA. IgM can be dissociated through the cleavage of covalent bonds interconnecting the sub-units by the use of 2-mercaptoethanol 2-ME or dithiothreitol DTT.
The presence of IgA in secretions is believed to be due to local production rather than transportation from plasma. In secretions IgA occurs as a dimmer. P and MNS. IgM may interfere with detection of clinically significant IgG antibodies by masking their activity.
IgA does not fix complement and is not transported across the placenta. IgM in plasma have half-life of 5 days. The function of the complement system is the lysis of the cells through interaction with antibodies. The complement system consists of a group of serum proteins that circulate in an inactive pro-enzyme state and are activated in a very precise biochemical sequence.
By the age of 2 years. IgM is the only type of immunoglobulin made by the fetus before and at the time of birth. At birth.
Since IgM is not transferred across the placenta. The proteins in Several IgM antibodies can be found in cord serum. The concentration of IgM starts to rise within days after birth. IgA cannot be detected in the cord serum. The activated antigen-antibody-C 1 complex now is capable of interacting with the next complement component C4 in sequence.
This reaction involves cleavage of the component C2 into a small free-floating C2b fragment and has no biological activity. These two ways are: In many cases activation of the proteins is associated with cleavage of protein component. In the end terminal membrane attack complex C5b is formed which lysis the cell. Membrane attach complex-Membrane bound C5b binds C6. Erythocytes antigen-antibody complexes activate the complement proteins C1-C9 by specific immune response. The activated C4b molecules on the cell surface attacks the proenzyme molecules C2.
Activation of the classic complement pathway is initiated by interaction of antigen with complement fixing antibody. This complex attaches to the cell membrane and binds C8.
Not all immunoglobulns Ig activate the classic pathway. The nature of antigen-antibody-C1 interaction is not clear. CI is a complex protein compound of three subunits. C5a and C5b. Activated C5b attaches to the cell membrane and is the nucleus for the formation of membrane attach complex.
C4a floats free in the surrounding medium. C3b is bound to the erythrocyte membrane and form activated C4b2a3b complex. After this Clqrs and immunoglobulin are no longer needed.
The larger C2 a fragment attaches to the cell surface leading to the formation of activated C4b2a complex attached to the cell surface.
C3a is released into surrounding medium and has anaphylatoxins activity. Sequence of Reactions of the Classic Pathway This pathway is mostly responsible for the lysis of antibody sensitized red cells.
The smaller fragment often has the function of promoting the inflamatory response. The binding of CI to antibody leads to activation of CI. These proteins can be activated by two main pathways using specific and non-specific immune mechanism that convert the inactive proenzymes into active enzymes. Principles of Immunohematology complement system are given either numerical or letter designations. C5a is released into the surrounding medium and has anaphylatoxins activity. This activation causes cleavage of CI into Clq.
The larger fragment produced by the protein cleavage is responsible for continuation of the complement activation sequence. C4 is cleaved by C1. The C14b2a3b can bind and cleave C5 into two fragments. The complement proteins are activated by innate.
Alternative Complement Pathway The alternative pathway does not utilize the classic complement components.
The classic pathway utilizes C1. C3b molecules bound to the surface of the target cells. Factor D is analogous to CI of the classic pathway.
Factor B is analogous to C2 and is important in the cleavage of C3. Small amount of C3b is generated continuously owing to the spontaneous hydrolytic cleavage of C3 molecules. The activated complement complex is indicated by the bar above the letters and numbers. Four proteins participate in the alternative pathway: See Fig.
B and C3. C4 and C2 and also does not have an absolute requirement of antibody. This activated enzyme C3bBb interact with C3 of the classic pathway and form C3Bb3b which activate C5 as in classic pathway and complement cascade continues.
Whole human serum is used for the preparation of polyspecific broad spectrum sera which contains antiglobulin antibodies IgG and anti-complement antibodies like C3b. IgG autoantibodies or complement components.