Process of making TPA

1. mRNA of the TPA gene has been isolated from human cells.
2. cDNA is made from mRNA.
3. Recombinant DNA is created by combining cDNA with plasmids.
4. Recombinant DNA is introduced into host cells.
5. Hosts with recombinant DNA are cultured in culture medium and thousands of copies are made.
6. Medicines are prepared by isolating the TPA protein from the host.
7. Pushing TPA injection into the blood vessel of a heart attack or stroke patient dissolves the blood block and the patient recovers.

What is TPA (Tissue Plasminogen Activator)

Human blood contains the enzyme plasmin. The plasmin enzyme exists in the blood in the form of plasminogen. Plasminogen is inactive. TPA converts inactive plasminogen to active plasminogen. Activated plasminogen dissolves blood clots in the human body. The process of dissolving clotted blood is called fibrinolysis. Protects people from heart attack or stroke. Heals the patient by dissolving the blood block. In 1970, the enzyme streptokinase was isolated from bacteria, which dissolves clotted blood.

Importance, function of interferon

1. It inhibits the growth of virus.
2. It regulates the immune system.
3. | Prevents the increase in the number of B and T lymphocytes. Cures viral diseases.
4. Prevents the growth of cancer cells by increasing the capacity and number of Natural Killer Cells.
5. Destroys cancer cells by increasing the host’s immunity.
6. It inhibits the production of antibodies. Stimulates innate antioxidant capacity and reproduction.
7. Interferon is used to treat complicated hepatitis-B, herpes, papilloma etc.
8. It is effective against the rabies virus.

Steps in interferon production

1. Target gene selection and isolation: DNA is collected from human fibroblast cells. The gene carrying the interferon code (interferon-beta) is isolated from the DNA.
2. Carrier Selection: Carriers are selected to carry the target gene. Plasmids act as DNA carriers.
3. Local Excision of Plasmid DNA: Specific regions are excised from the carrier plasmid DNA using restriction enzymes.
4. Preparation of recombinant DNA: The interferon gene is ligated to the carrier plasmid DNA by ligase enzymes. As a result, recombinant DNA is produced.
5. Introduction of Recombinant DNA into Host: Recombinant DNA is introduced into cells of host E. coli bacteria. The process of introducing recombinant DNA into bacterial cells is called transformation.
6. Amplification of Recombinant DNA: After the recombinant DNA is introduced into the host cells, the host bacteria are cultivated in culture medium. Within a short period of time, the bacteria multiply in the culture medium to produce thousands of copies. Recombinant DNA is also produced. During this time the bacteria secrete interferon through the culture.
7. Isolation of Interferon: Interferon is isolated from the culture medium. It is then purified by chemical means.
Each yeast cell produces one million (10 lakh) molecules of interferon. 1×105 molecules of interferon are produced inside E. coli.

What are Interferons?

Interferon is a high molecular weight protein. Small groups of proteins with a molecular weight of 20,000-30,000 daltons are called interferons. It is a protective protein. Interferon is produced by E. coli and yeast. The commercial name of interferon is Betaferon. It is of three types. α-interferon β-interferon and γ-interferon.
In 1957, British scientists Alick Isaacs and Jean Lindermann discovered interferon. In 1980, American scientists Gilbert and Weissmann (Gilbert & Weissmann) were able to produce human interferon.

Steps in the insulin production process

1. Synthesis of Polynucleotide Chains: Insulin molecules are composed of two polynucleotide chains. A chain and B chain. A chain consists of 21 and B chain of 30 amino acids. A chain of 63 nucleotides and B chain of 90 nucleotides are made chemically in the laboratory. Then the two chains are purified.
2. Production of recombinant DNA: Carrier bacteria are selected. Plasmid DNA is isolated from bacterial cells. Restriction enzymes are used to remove certain parts from A chain and B chain. Again, corresponding segments are cut from plasmid DNA using the same enzyme. However, the portion of the plasmid DNA that produces the gene for the β-galactosidase enzyme is cut out. The A chain and B chain are then joined to separate plasmid DNA with the help of ligase enzyme. Recombinant DNA is formed as a result of ligation of A chain and B chain with plasmid DNA. Thus two types of recombinant DNA are produced. A strand is recombinant DNA and B strand is recombinant DNA.
3. Introduction of Recombinant DNA into Host: Recombinant DNA is introduced into host bacterial cells during the transformation process. This is done by heat-shock method or electric pulse method. The host (E. coli) is first placed in CaCl2 solution and then on ice for 14-16 hours. It binds Ca to the host cell wall. A mixture of host and recombinant DNA in a container was placed on ice for 30 min, at 420°C for 90 s, and again on ice for 2 min. In this the host (E. coli) absorbs the recombinant DNA.
4. Gene Cloning: Host bacteria (E. coli) with recombinant DNA are grown in culture medium in fermentation tanks. As the number of E. coli bacteria increases, recombinant DNA copies are also produced. This results in β-galactosidase A chain and β-galactosidase B chain. Also some methionine is produced.
5. Separation of the two chains: A chain and B chain of the polynucleotide are separated from the culture medium. The resulting methionines with the A chain and B chain are then removed using cyanogen bromide. The two chains are then chemically purified.
6. Preparation of Insulin Molecule: In sulfonating process, A chain and B chain of nucleotides are combined in presence of sodium disulfonating and sodium sulfite. The two chains are then recombined by a disulfide bond.
7. Purification of insulin: The insulin produced contains the bacteria’s own protein. Therefore the extracted insulin is chemically purified.
8. Insulin Market Types: Pure insulin is filled in suitable ampoules. Then it is marketed.

Insulin discovery and research

In 1916, Sir Edward Sharpe Shaffer discovered insulin secreted by the human pancreas. In 1921, Canadian physiologists Banting and Best described the antidiabetic role of insulin. In 1923, Eli Lilly collected and marketed insulin from the pancreas of pigs and cows. In 1954, Frederick Sanger discovered the amino acid sequence and chemical structure of human insulin. In 1977, Itakura and his colleagues first synthesized two chains of human insulin. In 1980, Novo Industry of Denmark converted pig insulin into 99% pure human insulin. In 1981, scientists at Hope National Medical Center in California produced pure human insulin. In 1982, Eli Lilly commercially produced human insulin called Humulin. Currently, companies such as Genintech, Novo Industries, Biogen, Eli Lilly etc. are commercially marketing pure human insulin.

What is insulin?

Insulin is a type of hormone. Insulin is the hormone released from the beta (β) cells of the pancreas that controls diabetes by accelerating the uptake of blood glucose. Insulin is a type of small protein. Pro-insulin consists of four parts. Anterior part and A, B and C parts. Insulin is made by removing the C portion of pro-insulin and joining the A and B portions by a disulfide bond. Human insulin contains 17 types of 51 amino acids. Its chemical symbol is C254H377N65O75S6 and molecular mass is 5734. The DNA molecule at the top of the short arm of human chromosome 11 contains the insulin producing gene. It consists of 153 nitrogenous bases. E. coli bacteria contain 1×105 (10 lakh) insulin molecules.