How Can You Tell Which Receptor Your HIV Uses?

How Can You Tell Which Receptor Your HIV Uses?

Since CCR5 inhibitors only work on virus that uses the CCR5 receptor, it makes sense that your doctor would have to know which type of virus your HIV is; one that uses CCR5 or one that uses CXCR4. There is a way to tell which type of virus you have using a blood test called the Trofile Assay.

The Trofile Assay

The trofile assay is a type of genetic testing of a person's blood. The virus in a blood sample is tested against cells that are CCR5 and CXCR4. If the HIV only replicates in the presence of the CCR5 cells, it is said to be CCR5 tropic or R5 for short. If, on the other hand, the virus only replicates in the presence of the CXCR4 cells, it is said to be CXCR4 tropic or X4 for short. On those occasions when HIV replicates in the presence of both CXCR4 and CCR5 cells, it is said to be dual tropic.

Once a person's HIV is identified as either R5 of X4, an HIV medication regimen can be developed accordingly; a Maraviroc containing regimen for people who are R5 and a regimen without Maraviroc for X4. For those people dual tropic, a regimen may or may not contain Maraviroc.

Currently the Trofile Assay is the only test available to type a person R5, X4, or dual tropic. At $1,500, the price is a bit steep especially for people without insurance. Other companies are at work trying to develop cheaper and more sensitive HIV tropism tests.

How Can You Tell Which Receptor Your HIV Uses?

Since CCR5 inhibitors only work on virus that uses the CCR5 receptor, it makes sense that your doctor would have to know which type of virus your HIV is; one that uses CCR5 or one that uses CXCR4. There is a way to tell which type of virus you have using a blood test called the Trofile Assay.

The Trofile Assay

The trofile assay is a type of genetic testing of a person's blood. The virus in a blood sample is tested against cells that are CCR5 and CXCR4. If the HIV only replicates in the presence of the CCR5 cells, it is said to be CCR5 tropic or R5 for short. If, on the other hand, the virus only replicates in the presence of the CXCR4 cells, it is said to be CXCR4 tropic or X4 for short. On those occasions when HIV replicates in the presence of both CXCR4 and CCR5 cells, it is said to be dual tropic.

Once a person's HIV is identified as either R5 of X4, an HIV medication regimen can be developed accordingly; a Maraviroc containing regimen for people who are R5 and a regimen without Maraviroc for X4. For those people dual tropic, a regimen may or may not contain Maraviroc.

Currently the Trofile Assay is the only test available to type a person R5, X4, or dual tropic. At $1,500, the price is a bit steep especially for people without insurance. Other companies are at work trying to develop cheaper and more sensitive HIV tropism tests.