Posts tagged HIV prevention
Are You More Immune to HIV Than You Thought?
9 years ago
by ADMIN
in HIV Management
For the past several decades, doctors and scientists could not understand why some people quickly get sick – and can die – when infected with HIV, while others seem to naturally resist the virus for several years with less damage done to their immune systems. Researchers at the University of Minnesota’s College of Biological Sciences and Medical School looked at the virus’s rapid-mutation ability, along with how it attacks the human immune system to replicate, and hypothesized that this distinct difference in how the virus differently affects infected individuals is somehow caused by the genetics of the infected host. In trying to understand why some are more immune to HIV than others, these researchers discovered a new crack in the HIV cell’s armor which helps explain this phenomenon.
HIV attacks the immune system in order to replicate within the infected host’s cells. It seeks out the immune system cells called T lymphocytes (T cells), and uses the cell’s molecular machinery to replicate within them, killing the cells when it is done with each cell. This infection eventually depletes the system of necessary T cells, leaving the infected host helpless to other invading viruses and bacteria. The T cells do have a defense against this, as they have an anti-virus protein in their arsenal – called APOBEC3 – which has the ability to block the HIV cell’s replication process. If they are successful, they can effectively stop the virus from replicating and eventually clear it from the system as the virus cells die off. Unfortunately, HIV has developed a counter-attack to this protein, a protein of their own – called Vif – which attach themselves to the APOBEC3 cells and trick the T cells into destroying their own protein, leaving them defenseless to the virus’s replication and destructive abilities. To learn why some seem to be able to naturally fend off the virus – at least for a lot longer than others – researchers looked closer at these proteins. They found strong clues as to why some immune systems work better against the virus than others.
Some people have a greater ability to create a version of the APOBEC3 protein, which is known as APOBEC3H. This particular form of the protein is boosted whenever someone is infected with HIV, which made the researchers believe this plays an important role in the immune system’s defense against HIV. What they found was a confirmation of this assumption, as people with a more stable accumulation of the APOBEC3H protein seem to be more naturally immune to HIV than those with a more unstable accumulation of this protein. Whenever the infecting HIV cells had a weaker version of their Vif protein (as constant mutations cause the virus to be varied in its strengths and weaknesses), the infected individual with a stable APOBEC3H protein in their T cells had a better time limiting the HIV cells from replicating. This was not the case if the infecting virus cells were equipped with a stronger Vif protein. This discovery helps scientists and doctors with a new path towards attacking HIV, with a possible road to a cure. The more we can suppress the virus’s Vif protein, the more our natural immune system has a chance to combat against the infection. Coupled with a strong antiretroviral regimen, this could help stop the virus from replicating, and possibly killing it outright.
Heroin Withdrawal Quickens the Spread of HIV, Researchers Say
9 years ago
by ADMIN
in HIV Management
With the hypothesis that heroin use contributes to a faster spread of the HIV cells in an infected person’s body, researchers out of Yale University conducted a study to look at the link between opiate use and HIV. They teamed up with scientists from Boston University and in Russia, studying participants’ CD4 count to determine their results. These results were quite different than they imagined, as the participants who claimed heavy heroin abuse had higher levels of CD4 than those who claimed only intermittent usage. With this information, the team has concluded that heroin withdrawal quickens the spread of HIV in an infected person’s body, as opposed to a steady use of the narcotic. CD4, which refers to a cluster of differentiation 4, is a specific form of protein that is typically found on immune system cells such as T helper cells and macrophages. This combination of the protein and immune cell, commonly known as white blood cells, are necessary for a healthy immune system to work properly, or at all. Because of this, the amount of CD4 protein found in a person’s body is a good indicator of how well their immune system is working, as lower amounts of these CD4 cells means a weaker or compromised immune system. Fewer CD4 cells in an HIV infected person’s body means the virus has destroyed more of the T helper cells where this glycoprotein is found.
Using this method of determining how much HIV has spread throughout an infected person’s body, the international research team looked at seventy seven participants, all from Russia, all heavy alcohol consumers, and none whom were then on antiretroviral medication. Those who self-reported no usage of heroin had a standard depletion rate of CD4 cells. This came as no surprise to the teams. What was surprising was the fact that those who reported heavy opiate usage had a slower rate of CD4 depletion than those who only occasionally used the drug. This ruled out the notion that heroin speeds up the spread of HIV cells in an infected person’s body, and opened new questions to the teams. Their conclusion is that it isn’t heroin use that speeds up the replication process of HIV – as previously believed – but that heroin withdrawal is the factor that quickens the spread of HIV. Though they cannot yet determine why this is, they do know that heroin withdrawal is one of the worst known to mankind, and like alcohol and benzodiazepines it is one of the only three categories of withdrawals which can actually kill a person. Jennifer Elelman, the lead author of the study and assistant professor at Yale School of Medicine, said, “We expected that HIV-positive patients who abused heroin on an ongoing basis would have the greatest decreases in their CD4 count,” adding that the international research team is now looking at the withdrawal process in relation to the spread of HIV. Not to leave all of their previous assumptions behind as they look at this process, Dr. Edelman continued, “We will also evaluate the effects of heroin and other opioids on other aspects of immune function.”
Low Risk of Birth Defects
9 years ago
by ADMIN
in HIV and Pregnancy
Low Risk of Birth Defects: HIV and Antiretroviral Medication
With new compounds and therapies expanding what can be done for individuals living with HIV, more and more infected women are looking towards pregnancy and childbirth. The combination of pregnancy and the latest antiviral medications is always a cause of concern, as we often don’t have enough data to make a definitive decision on whether a certain medicine should be given to an individual while pregnant. We also need to know when it is most likely for a mother to infect her infant, and which medicines are best at keeping the rate of infection low. Certainly, many antiretroviral drugs developed in the fight against HIV have been thought to increase the potential of birth defects in the unborn children. A new study, however, shows the opposite. Indeed, it confirms a low risk of birth defects by antiretroviral medications used during pregnancy.
This study – the Pediatric HIV/AIDS Cohort Study (PHACS) Surveillance Monitoring of ART Toxicities (SMARTT) study – released its findings on 10 November 2014. Atazanavir was the only antiretroviral drug that was shown to increase the otherwise low risk of birth defects among HIV-positive women. This medication showed a 2-fold increase in the risk of birth defects, particularly musculoskeletal and skin anomalies. However, another study confirmed that at least three varied regimens of anti-HIV medications—that did not include atazanavir—was safe for women who are expecting. In fact, all other antiretroviral, anti-HIV medications tested in these studies showed no increase in the risk of birth defects. This is great news for HIV infected women who still want to become mothers. With the risks of infecting their child minimal, and the side effects almost non-existent, the hopes of researchers are high that we will find ways to altogether eliminate the transfer of HIV between mother and child.
Alternative HIV Regimens
9 years ago
by ADMIN
in HIV Research
Alternative HIV Regimens: For Those Unable to Use Efavirenz
The most commonly prescribed HIV therapies includes efavirenz, which is one of the key ingredients in stopping the spread of HIV cells through the body and keeping the immune system functioning and optimal. Efavirenz is never prescribed alone, however in combination with other anti-HIV drugs it has proven to have the greatest overall results in keeping the HIV viral load down and the immune response minimal. Unfortunately, the side effects can prevent some people from taking efavirenz. The adverse effects can include insomnia, nightmares, confusion, memory loss, headaches and depression. Along with these psychiatric disorders, efavirenz has also been known to cause birth defects in children whose mothers used the drug. Because of these consequences, it is highly recommended that anybody who suffers from certain psychiatric conditions, or any woman who believes they are pregnant, or are trying to pregnant, should not take efavirenz. Luckily, for patients who are HIV positive and unable to take efavirenz, there are alternative HIV regimens found to be effective in keeping the virus under control and unable to attack the immune system.
Researchers at the AIDS Clinic Trials Group (ACTG), have conducted a Phase III, randomized study of regimens which do not use efavirenz. They studied three different therapies given to over 1,800 HIV positive adults. The results were uniformly positive. The in-depth study closely followed the participants for 96 weeks. At the end of the study, it was ascertained that all three regimens were effective in keeping the viral loads down and keeping the immune systems healthy. There were variations in how easily patients were able to withstand any negative effects of the drugs while still gaining all of the positive effects. One regimen was clearly superior in this category – the raltegravir-based therapy – but all three were reasonable for lifelong medical regimens. These alternative HIV regimens that are effective in patients not eligible for efavirenz has provided another outlet of hope for first line defense against HIV infection.
Prevent the Spread of HIV Infection
9 years ago
by ADMIN
in HIV Prevention
Prevent the Spread of HIV Infection: Nanofiber-Based Technology Could Help
Human Immunodeficiency Virus (HIV) is spread through direct contact with blood, semen, pre-seminal fluid, vaginal fluids, fecal matter, breast milk, and other heavy fluids that our bodies produce. This virus attacks the T lymphocytes, a type of white blood cell that is a part of your immune system and prevents infections and diseases. Without treatment to prevent the virus from replicating itself, these T Cells eventually will become depleted. It is estimated that more than one million people over the age of thirteen are living with HIV infection. Of this number, roughly two hundred thousand infected people are unaware that they are HIV positive. The current therapies that stop the virus from replicating and spreading through the bloodstream will also stop the negative effects of HIV. However, they do not completely rid the body of the virus and do not prevent the possibility of further infection from occurring. Fortunately, there are new treatments in development that could actually prevent the spread of HIV infection around the world.
Of these new forms of prevention being developed, a group of researchers based out of the University of Missouri-Kansas City School of Pharmacy are testing a novel nanofiber-based technology. The aim is to prevent the transmission of HIV through vaginal mucus membranes. This vaginal-based drug is applied to the area prior to sexual contact, and is designed to take effect upon the presence of semen enzymes. The drug inactivates and kills any present HIV cells in the enzymes—prior to exposure and penetration of vaginal fluids. This is the main cause of heterosexual HIV transmission, HIV infected semen enzymes penetrating into the vaginal fluids and infecting the host, and this technology has been shown to effectively prevent the spread of HIV infection in this matter. They are working on using this technology in male-to-male sexual contact as well, and preliminary research looks positive.
