Agglutinin Health Dictionary

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Agglutinin: From 1 Different Sources

Agglutinogen

An ANTIGEN that stimulates production of an agglutinin – an antibody that causes AGGLUTINATION or clumping of bacteria, blood cells or other antigenic particles. In the case of blood cells, this should not be confused with the clumping that happens in blood COAGULATION, which is a di?erent process.... agglutinogen

Abrus Precatorius

Linn.

Family: Papilionaceae; Fabaceae.

Habitat: Throughout the country, ascending to an altitude of about 1,050 m in the outer Himalayas.

English: Indian Wild Liquorice, Jequirity, Crab's Eye, Precatory Bean.

Ayurvedic: Gunjaa, Gunjaka, Chirihintikaa, Raktikaa, Chirmi- ti, Kakanti, Kabjaka, Tiktikaa, Kaakananti, Kaakchinchi. (Not to be used as a substitute for liquorice.)

Unani: Ghunghchi, Ghamchi.

Siddha/Tamil: Kunri.

Folk: Chirmiti, Ratti.

Action: Uterine stimulant, abortifa- cient, toxic. Seeds—teratogenic. A paste of seeds is applied on vitiligo patches.

Along with other therapeutic applications, The Ayurvedic Pharmacopoeia of India has indicated the use of seeds in baldness.

Seeds contain abrin, a toxalbumin, indole derivatives, anthocyanins, ste- rols, terpenes. Abrin causes agglutination of erythrocytes, haemolysis and enlargement of lymph glands. A non- toxic dose of abrin (1.25 mcg/kg body weight), isolated from the seeds of red var., exhibited a noticeable increase in antibody-forming cells, bone marrow cellularity and alpha-esterase-positive bone marrow cells.

Oral administration of agglutinins, isolated from the seeds, is useful in the treatment of hepatitis and AIDS.

The seed extract exhibited antischis- tosomal activity in male hamsters.

The methanolic extract of seeds inhibited the motility of human spermatozoa.

The roots contain precol, abrol, gly- cyrrhizin (1.5%) and alkaloids—abra- sine and precasine. The roots also contain triterpenoids—abruslactone A, methyl abrusgenate and abrusgenic acid.

Alkaloids/bases present in the roots are also present in leaves and stems.

A. fruticulosus Wall. Ex Wight and Arn. synonym A. pulchellus Wall., A. laevigatus E. May. (Shveta Gunjaa) is also used for the same medicinal purposes as A. precatorius.

Dosage: Detoxified seed—1-3 g powder. Root powder—3-6 g. (API Vols. I, II.)... abrus precatorius

Agglutination

(clumping) n. the sticking together, by serum antibodies called agglutinins, of such microscopic antigenic particles as red blood cells or bacteria so that they form visible clumps. Any substance that stimulates the body to produce an agglutinin is called an agglutinogen. Agglutination is a specific reaction; in the laboratory, sera containing different known agglutinins provide an invaluable means of identifying unknown bacteria. When blood of different groups is mixed, agglutination occurs because serum contains natural antibodies (isoagglutinins) that attack red cells of a foreign group, whether previously encountered or not. This is not the same process as occurs in *blood coagulation.... agglutination

Blood Groups

People are divided into four main groups in respect of a certain reaction of the blood. This depends upon the capacity of the serum of one person’s blood to cause the red cells of another’s to stick together (agglutinate). The reaction depends on antigens (see ANTIGEN), known as agglutinogens, in the erythrocytes and on ANTIBODIES, known as agglutinins, in the serum. There are two of each, the agglutinogens being known as A and B. A person’s erythrocytes may have (1) no agglutinogens, (2) agglutinogen A, (3) agglutinogen B, (4) agglutinogens A and B: these are the four groups. Since the identi?cation of the ABO and Rhesus factors (see below), around 400 other antigens have been discovered, but they cause few problems over transfusions.

In blood transfusion, the person giving and the person receiving the blood must belong to the same blood group, or a dangerous reaction will take place from the agglutination that occurs when blood of a di?erent group is present. One exception is that group O Rhesus-negative blood can be used in an emergency for anybody.

Agglutinogens Agglutinins Frequency
in the in the in Great
Group erythrocytes plasma Britain
AB A and B None 2 per cent
A A Anti-B 46 per cent
B B Anti-A 8 per cent
O Neither Anti-A and 44 per cent
A nor B Anti-B

Rhesus factor In addition to the A and B agglutinogens (or antigens), there is another one known as the Rhesus (or Rh) factor – so named because there is a similar antigen in the red blood corpuscles of the Rhesus monkey. About 84 per cent of the population have this Rh factor in their blood and are therefore known as ‘Rh-positive’. The remaining 16 per cent who do not possess the factor are known as ‘Rh-negative’.

The practical importance of the Rh factor is that, unlike the A and B agglutinogens, there are no naturally occurring Rh antibodies. However, such antibodies may develop in a Rh-negative person if the Rh antigen is introduced into his or her circulation. This can occur (a) if a Rh-negative person is given a transfusion of Rh-positive blood, and (b) if a Rh-negative mother married to a Rh-positive husband becomes pregnant and the fetus is Rh-positive. If the latter happens, the mother develops Rh antibodies which can pass into the fetal circulation, where they react with the baby’s Rh antigen and cause HAEMOLYTIC DISEASE of the fetus and newborn. This means that, untreated, the child may be stillborn or become jaundiced shortly after birth.

As about one in six expectant mothers is Rh-negative, a blood-group examination is now considered an essential part of the antenatal examination of a pregnant woman. All such Rh-negative expectant mothers are now given a ‘Rhesus card’ showing that they belong to the rhesus-negative blood group. This card should always be carried with them. Rh-positive blood should never be transfused to a Rh-negative girl or woman.... blood groups


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