Interaction with other pathogens may also increase the likelihood that AIDS will develop. Specifically, a herpes virus called human B-cell lymphotropic virus (HBLV) or human herpes virus 6 (HHV-6) that was discovered in the laboratory of one of us (Gallo) can interact with HN in a way that may increase the severity of HN infection. Ordinarily HHV-6 is easily controlled by the immune system. In a person whose immune system is impaired by HN, however, HHV-6 may replicate more freely, becoming a threat to health. In addition, although one of the main hosts of HHV-6 is a white blood cell called the B cell, the virus , can also infect T4 lymphocytes. If the T cell is simultaneously infected by HN, HHV-6 can activate the latent AIDS virus, further impairing the immune system and worsening the cycle.
Clearly, in spite of rapid progress there are many gaps in our understanding of HN and AIDS. Should we panic? The answer is no, for several reasons. The most obvious is that panic does no good. The second reason is that it now seems unlikely HIV infection will spread as rapidly outside the original high-risk groups in the industrial countries as it has within them. A third reason is that this disease is not beyond the curative power of science. Although current knowledge is imperfect, it is sufficient to provide confidence that effective therapies and a vaccine will be developed.
The possibilities for therapy are particularly impressive. In the first phase of the search for AIDS therapies it was necessary to exploit any drug that seemed to provide even a remote chance of combating HIV infection. A variety of compounds formulated for other purposes were taken off the shelf and tested. Most were of little value, but one (AZT), originally formulated as an anticancer drug, turned out to be the first effective anti-AIDS agent. More recently, an experimental regimen in which AZT is alternated with the related compound known as dideoxycytidine offers even greater promise.
Bringing AZT into clinical use was a significant accomplishment, because it gave hope that AIDS would not remain incurable forever. As a form of therapy, however, AZT is not perfect and will probably be supplanted by less toxic agents formulated on the basis of what is known about the HIV life cycle. One promising agent is CD4, the molecule that serves as the viral receptor. Early tests show that soluble CD4 can bind to the virus and prevent it from infecting new cells. Many other drugs are in trials; one of them, perhaps combined with compounds that bolster the immune system, may provide therapy for HIV infection.
In assessing the progress that has been made toward achieving fully effective AIDS therapy, it must be kept in mind that this work has two facets. In addition to combating a complex and evasive pathogen, it must pioneer entirely new areas of medicine. The reason is that there are few effective treatments for viral diseases-and almost none for retroviruses. There are various reasons for this, among them the fact that viruses (unlike bacteria, for which effective therapies exist) always appropriate the biosynthetic apparatus of the host cell. As a result drugs effective against viruses tend to damage mammalian cells. Yet we are confident that the dual goals of pioneering science and clinical effectiveness will be met.
What is true of therapy is also true of vaccines: an AIDS vaccine will be a pioneering scientific achievement. Since the HIV genome has the capacity to integrate into the chromosomes of the host cell, little serious consideration has been given to using preparations containing the whole virus as a vaccine. An AIDS vaccine must consist of subunits, or parts, of the virus in the right combination. Yet experience with subunit vaccines is slight. Indeed, so far only a few subunit vaccines have proved practical. Much work is under way to find the combination of HIV subunits that will yield the greatest protective response. As in the case of therapy, we believe there will be a practical vaccine against HIV.
Perhaps an even more persuasive reason for hope is that even without a vaccine or a cure, what is already known could bring the epidemic under control. The blood supply has already been largely secured by the presence of a blood test. Moreover, the modes of transmission of HIV-blood, sexual intercourse and from mother to child-are firmly established. Hence any individual can drastically reduce his or her risk of infection. If such knowledge were applied everywhere, there would be a sharp leveling off in the spread of HIV infection, as there has been in some groups in the developed world. The lesson here is that there is a need for education about HIV infection--in clear, explicit language and as early as possible.
Yet there are parts of the epidemic where education alone is not sufficient, and it is in those areas that humanity will be tested. Users of intra· venous drugs, for example, are notoriously resistant to educational campaigns alone. It seems clear that the effort to control AIDS must be aimed in part at eradicating the conditions that give rise to drug addiction. Those conditions are in turn linked to social and economic patterns. Eliminating the disease may entail eliminating some of the social differentials that form the substratum of drug abuse.
It is also the case that in some areas of the developing world education alone will not stem the epidemic. Education is necessary, but it must be accompanied by other measures. In central Africa--the part of the world most beleaguered by AIDs--there are few facilities for blood testing and few technicians trained to perform tests. Furthermore, the blood tests used in the U.S. and Western Europe are too expensive to be helpful. As a result the virus is still being spread by contaminated blood, long after that form of transmission has been practically eliminated in the industrial countries.
To help change this situation the World AIDS Foundation has made improving the situation in central Africa its highest priority. The foundation (along with its parent, the Franco-American AIDS Foundation) was formed as part of the agreement that resolved a lawsuit between France and the U.S. over the AIDS blood test. The parent foundation receives 80 percent of the royalties from the French and American blood tests; the World AIDS Foundation in turn receives 25 percent of that. Much thought has been given to how to allocate the funds, and the first project (carried out in conjunction with the World Health Organization) will be realized in several African countries. It will include training technicians to perform blood tests, establishing one HIV-free blood center and increasing public education about HIV transmission.
Efforts such as this one, coupling public and private funds and energies, will be essential to stopping AIDS. As we stated above, both of us are certain that science will ultimately find a cure and a vaccine for AIDS. But not tomorrow. The AIDS virus (and other human retroviruses) will be with us for a long time. During that time no intelligent person can expect the necessary solutions to come solely from authorities such as scientists, governments or corporations. All of us must accept responsibilities: to learn how HIV is spread, to reduce risky behavior, to raise our voices against acceptance of the drug culture and to avoid stigmatizing victims of the disease. If we can accept such responsibilities, the worst element of nightmare will have been removed from the AIDS epidemic.
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Add CommentEarly on ciclosporin was used to try and save Rock Hudson just before he died. The Doctors treating him apparently thought what was happening to the immune system resembled rejection or allergic response to self.
Reply | Report Abuse | Link to thisThe response apparently was dramatic. His t-cells skyrocketed in #.
He was too far gone though, for he died very shortly thereafter, and this line of reasoning on how to treat the then unknown viral infection was dropped in favor of pursuing angles the medical establishment favored.
Medical research like all science can be rigid when it comes to trying something new, and trying to re-imagine HIV as a virally induced allergy for experimental treatment's sake just goes against the ingrained accepted notions on what HIV is and how to treat it.
Everything is focused on finding a way to eradicate it from the system or limit its ability to reproduce or a vaccine.
While there were a few incidences of experimentation with ciclosporin beyond Hudson, all were dropped when the patient died. It was considered a "what do you have to lose" option.
Unfortunately, for some odd reason, because ciclosporin did not produce a miracle interested disappeared.
It never was tried in a proper setting where the patients were NOT at death's door, despite evidence that when tried on close to death patients the effects on the immune system was dramatic showing a marked transient jump in T-cells.
Ciclosporin deserves its day in the sun.
Perhaps it can modulate the overactive immune system downward enough so that T-helper cells don't go killing each other confusing each other with HIV, because HIV's coating is a product of the T-Cell outer envelope.
Once slowed down by ciclosporin perhaps the immune system would be more able to appropriately distinguish infected from healthy and properly manage the infection - turning it into a mild chronic infection rather than the killer it still is in many areas.
Of course, the biggest obstacle to even trying this is that ciclosporin is not going to make the big bucks the new anti-virals are, so its in the interest of big pharma to ignore it entirely no matter how positive the evidence is that such medications could play a successful role in managing the HIV infection.