Question 6 – Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only) - Questions

Maedi-Visna Virus (MVV) is a retrovirus that infects sheep. MVV binds to a primary receptor called CD209 on host macrophages. Current management of MVV relies on supportive care or daily administration of antiretroviral drugs (such as Tenofovir) to slow viral replication, but long-term Tenofovir use can cause severe renal toxicity.

Scientists investigated a new stem cell gene therapy ( $GT-209GT\text{-}209$ ) to treat MVV-positive sheep. $GT-209GT\text{-}209$ delivers a gene that knocks out the CD209 receptor gene in hematopoietic stem cells.

Scientists conducted a study on two small groups of MVV-positive sheep:

Group X (6 sheep) received the stem cell gene therapy along with a pre-treatment of chemotherapy (myeloablative busulfan) to deplete existing immune cells.
Group Y (6 sheep) received the stem cell gene therapy following a pre-treatment of targeted monoclonal antibodies to deplete macrophages.

Both groups stopped Tenofovir therapy 18 months after starting the gene therapy.

At 36 months after stopping Tenofovir therapy:

4 out of 6 sheep in Group X and 3 out of 6 sheep in Group Y showed complete remission, with no detectable MVV RNA in their blood plasma and no MVV DNA in their macrophages.
Macrophages in the remission sheep did not express the CD209 receptor.
Two sheep from Group X died from severe opportunistic fungal infections due to chemotherapy-related bone marrow suppression during the study.

Use the information provided to evaluate the use of stem cell gene therapy ( $GT-209GT\text{-}209$ ) to treat MVV infections.

Scientists conducted a study on two small groups of MVV-positive sheep:

Group X (6 sheep) received the stem cell gene therapy along with a pre-treatment of chemotherapy (myeloablative busulfan) to deplete existing immune cells.
Group Y (6 sheep) received the stem cell gene therapy following a pre-treatment of targeted monoclonal antibodies to deplete macrophages.

Both groups stopped Tenofovir therapy 18 months after starting the gene therapy.

At 36 months after stopping Tenofovir therapy:

4 out of 6 sheep in Group X and 3 out of 6 sheep in Group Y showed complete remission, with no detectable MVV RNA in their blood plasma and no MVV DNA in their macrophages.
Macrophages in the remission sheep did not express the CD209 receptor.
Two sheep from Group X died from severe opportunistic fungal infections due to chemotherapy-related bone marrow suppression during the study.

Use the information provided to evaluate the use of stem cell gene therapy ( $GT-209GT\text{-}209$ ) to treat MVV infections.

Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only)

Question 2

Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only)

Question 2

Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only)

Question 2

Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only) Questions

Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only)

Question 2

Gene technologies allow the study and alteration of gene function allowing a better understanding of organism function and the design of new industrial and medical processes (A-level only) Questions