Augmentation therapy, Biology

Assignment Help:

Augmentation Therapy:

The functional gene is introduced in addition to the defective gene endogeneous to the cell(s) in this somatic cell gene therapy,  i.e. the improved  cells consist  both the defective (endogeneous) and  the normal (introduced) copies of the gene. There are two basic approaches to augmentation therapy. First was used in the first two patients on whom gene therapy was attempted to right the genetic disorder known Severe Combined Immune Deficiency (SCID) syndrome formed by adenosine deaminase (ADA) deficiency. (i) General ADA gene copies were formed by cloning and then (ii) packed into a faulted retrovirus; mostly viral genes were replaced by the ADA gene. (iii) Lymphocytes were linked from the patients, and (IV) the recombinant retroviruses were used to infect the lymphocytes. And (v) the infected cells showing  the ADA gene were injected back into the patients. The usual ADA gene was expressed in the patients, and ADA deficiency was partially right, this resulted in an improvement in the patient's immune system.

Different kinds of viral vectors have been used to deliver genes into target/stem cells, like lymphocytes, cultured in vitro, bone marrow cells. The target cells themselves are obtained from the concerned patient (more desirable) or from a matched donor. The reservations about security of retroviral vectors is sought to be resolved by developing suicide vectors which cannot replicate after delivery of the gene. The other major problems of this approach are: (i) low frequency of transfect ion of stem cells, (ii) persist ability  of the integrated gene, (iii) duration of the gene expression,   (iv) lack of suitable regulation of gene expression etc. More recently, interest has targeted on physical methods of gene delivery like Ca2+ phosphate co precipitation, particle gun, electro oration etc.

The next approach is the direct injection of DNA into the tissues either as protein complexes (in order to bring about receptor-mediated transfer of DNA into a particular tissue, for example liver) or even as naked DNA into skin or muscle. Interestingly these cells obtain the DNA and show the gene product. Exciting results have been obtained with experimental familial hypercholesterolemia, where LDL receptor stage has been augmented by insertion of the gene as a sialoglycoprotein complex. The problems in this approach relate to the frequency of cells taking up and showing the gene and, more specifically, the duration of expression.

The gene delivery methods used for gene therapy may also be used for healing of cancer or AIDS. In the case of cancer, a toxin encoding gene can be delivered into the cancer cells. In the same way, appropriate interleukin genes can be delivered to boost up the body's defence mechanisms (in case of AIDS).


Related Discussions:- Augmentation therapy

Aschelminthes, in what part of the human body aschelminthes found?

in what part of the human body aschelminthes found?

Coniferous forests and taiga, As you travel south from the tundra you will ...

As you travel south from the tundra you will enter the circumpolar belt of coniferous forests which stretches across North America to Eurasia, this region is called taiga, a world

Why the vast majority of segregation errors in human patient, Which of the ...

Which of the following defines why the vast majority of segregation errors in human patients include the two sex chromosomes (XXY, XO, XYY) or chromosome 21 (triple 21)? A. Th

How is respiration performed by the larva of amphibians, Q. How is respirat...

Q. How is respiration performed by the larva of amphibians? The larva of amphibians has exclusively branchial respiration this is one of the reasons why it depends on water to

Cobalt (co) - micronutrients, Cobalt (Co) - Micronutrients The Co conc...

Cobalt (Co) - Micronutrients The Co concentration in the dry matter of plants grown in soil normally lies around 0.02 to 0.5 ppm. In soils the content varies from 1 to 40 ppm.

How tca cycle intermediates can be used as a substrae, Several TCA cycle in...

Several TCA cycle intermediates can be used as a substrate for the synthesis of other compounds. Succinyl CoA is on intermediate that is directly used for the synthesis of which of

Why fish and sea foods are important for human body, Why Fish and Sea Foods...

Why Fish and Sea Foods are important for human Body? They are rich sources of proteins (20-25%) of a high biological value. Dry fishes contain more (60%) proteins since most of

Which animals make cutaneous respiration, Q. Which animals make cutaneous r...

Q. Which animals make cutaneous respiration? Adult amphibians and Terrestrial annelids make cutaneous respiration in amphibians there is also pulmonary respiration, the thin sk

Microbodies, MICROBODIES Single unit membrane bound small spherical str...

MICROBODIES Single unit membrane bound small spherical structures. Microbodies are structurally related to lysosome. On the basis of functions microbodies are of four typ

Bio geographical evidences, The main points which is based on the seminar...

The main points which is based on the seminar topic Bio geographical evidences

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd