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VIRUS CLINIC
 Virus Medical Clinic, London - Centre for research, information, prevention and treatment using complementary and allopathic medicine.
Electronic microscopy of the fluvirus H1N1
...they are well known for causing disease, but most viruses coexist peacefully with their host.
ON THIS PAGE
# INTRODUCTION
# HOW VIRUSES REPLICATE
# ANTI VIRAL MEDICINE
# LASER THERAPY
# RETROVIRUSES of human importance and HIV/AIDS
INTRODUCTION
Medicine seems helpless when it comes to (most) viruses. The "harmless" ones disappear after a while, because ones immune system is capable enough to deal with them.
Then there are vaccinations, name them useful or call some of them dangerous... at least some are quite controversial.
Laser therapy can be part of a solution to tackle viruses... see
WHAT IS A VIRUS?
A virus is an intracellular parasite which grows inside the host cells. It uses the host's metabolic machinery. It is debatable whether viruses are truly living organisms. Specific viruses attack specific types of cells. F.e. respiratory syncytial viruses infect only the cells of the respiratory tract and bacteriophages attack only bacteria.
A VIRUS does not grow, but replicates
A VIRUS does not respire
A VIRUS does not move
A VIRUS is made of nucleic acid and a protein coat. Some viruses have an envelope, made of lipid and usually derived from the cell in which they grow. Other viruses are naked and just have their protein coat exposed, protecting the nucleic acid within the centre of the structure.
A VIRUS genome comprises of either RNA or DNA*
A VIRUS infects animals, plants, fungi, protists, bacteria and archaea
A VIRUS origin is unknown
*Retroviruses, like HIV, carry an RNA copy of the genome but upon infection of a host cell a cDNA copy of the virus RNA genome is made using the enzyme reverse transcriptase. A retrovirus has a genome comprising RNA in the virus particle. From this, the cDNA copy is made following infection of a new cell. The cDNA copy then integrates into its host cell genome.
VIRUSES CO-EVOLVED WITH THEIR HOSTS
Viruses were discovered in the late 19th century swhen the scientists Ivanowski (1892) and Beijerink (1898( worked independently with infected tobacco plants. Both demonstrated that there was an infectious agent that could pass through filters known to remove bacteria. This demonstrated the existence of an much smaller infectious agent, known today as the Tobacco Mosaic virus.
In 1796 a small pox vaccination was invented without knowing the (viral) cause of this disease!
1898 - the first animal virus was identified (Foot-and-Mouth virus)
1901 - the first human virus was identified (the Yellow Fever virus)
1917 - discovery of viruses that can infect bacteria
1918 - worldwide influenza epidemic
1939 - first visualisation of a virus with an electronic microscope
1962-70 - Mumps, Measles and Rubella (MMR)vaccine lincensed
1983 - identification of the Human Immunodeficiency Virus (HIV), the agent for AIDS.
Bird Flu H5N1
ANTIVIRAL MEDICINE
1. CONVENTIONAL APPROACHES... the long struggle
2. LASER THERAPY - the new way forward?
Rule: Antiviral drugs are available to treat only a few viral diseases. The reason for this is the fact that viral replication is so intimately associated with the host cell that any drug that interferes significantly with viral replication, is likely to be toxic to the host!
Confused? Just a little overview
ANTIMICROBIALS
(kill or inhibit growth of microbes)
Antimicrobials are:
ANTIBACTERIAL ANTIFUNGAL ANTIPARASITIC ANTIVIRAL
ANTIVIRALS
(kill or inhibit replication of viruses)
ZALCITABINE (1992) – anti-retroviral
CIDOFOVIR (1996) – against cytomegalovirus infections
ZANAMIVIR (1999) – against influenza
LOPINAVIR (2000) – anti-retroviral
The discovery of antibiotics (antibacterial chemotherapy) by Alexander Fleming was at least initially a big success and in the world of medicine enthusiasm was big. It was said that it might only take some years until bacterial infections are a thing of the past. But then…! Bacteria changed to adapt to new environments (like they always did), more and more different bacterial strains emerged, human immune-systems developed allergies to drugs and bacteria became and become more resistant to antibiotics. The incredible overuse of antibiotics plays a major role in resistance.
And ANTIVIRAL DRUGS?
After the success of antibiotics, the pharmaceutical industry launched huge programmes… with very little success. The key to success in drug development is specificity. Any stage of virus replication can be a target for a drug, but the drug must be more toxic to virus than to the host!
You go to your doctor with a viral infection and you will be told that you have a viral infection. As far as prescription medication goes... that's it! The doctor can't do anything except advising you to drink plenty and rest. If you are unlucky (and it happens very often), you will be prescribed antibiotics, which are not only useless, but can increase drug-resistance.
The idea to "blitz the bug and spare the host" might work sometimes with bacteria, but not with viruses, as viruses come only alive when it becomes part of the host by entering the cells.
Viruses (again a difference to bacteria) cannot live outside the host... as a virus... BUT! ... they can stay alive in its crystalline (dormant) structure. Italian scientists discovered intact smallpox viruses in a mummy from 1000 AD and were amazed to find, that they could culture the crystals of viruses and infect living cells.
The outside of every human cell has many receptors for the chemical messengers used to communicate between cells. The viral coat must fit exactly into the receptor. After the attachment, the receptor acts as a channel and the viral genetic information can travel into the cell, where it hijacks the cell and the new "cell machine" manufactures viral subunits, copies of the viral coat and all the enzymes and chemical messengers necessary to assemble many copies of the virus itself. And because all of this happens within a cell, the human immune system is not allert! Eventually the cell bursts and release uncountable copies of the virus into the bloodstream.
Antiviral drugs and antiviral herbs have to a certain extend the same approach once the virus starts to replicate: To disrupt the replication cycle of the virus.
When it comes to prevention, most antiviral drugs (like vaccines) are not very successful, but we do not know, whether antiviral herbs work better or not. Of course there are immune enhancing herbs and supplements, which will be at least a little effective... and never underestimate a placebo effect, which can also stimulate a positive immune response.
Once a virus is active and replicates in your body, many herbs can offer at least some relief and some help (f.e. Echinacea, which should not be used as a prevention herb, because it increases the white blood cells... and an increase in white blood cells - as a healthy person - makes you more prone to allergies and intolerances).
Some examples, how herbs can be helpful:
Prunellin, an active ingredient from Prunella vulgaris blocks cell receptors;
Baicalin from the Plantain and Skullcap interfere with the enzymes needed to make copies of viral components;
... and there are of course detoxification herbs which are helpful to eliminate the disease.
VIRUS CLINIC #03
LASER THERAPY
Laser Blood Irradiation Therapy/Transdermal Systemic Laser Therapy (TSLT)
…heal and increase functioning efficacy of the vascular, immune and respiratory system:
Currently the methods of laser and non-laser (incoherent monochromic, narrow-band or broadband) light blood irradiation therapy - the methods of photo-hemotherapy - are widely applied in the treatment of different pathologies. Direct intravenous and extracorporeal (with red, UV and blue light) as well as non-invasive transcutaneous (with red and infrared light) irradiation of blood are used. Unlike the treatment mechanisms of local laser therapy, the medical effects of photo-hemotherapy methods are determined by predominance of systemic healing mechanisms above the local ones, increasing the functioning efficacy of vascular, respiratory, immune, other systems and organism as a whole.
… normalisation of parameters of hormonal, immune, reproductive systems
The method of laser blood irradiation was developed in 1981 by the scientists E.N. Meshalkin and V.S. Sergievskiy. Originally the method was applied in the treatment of cardiovascular pathologies. Some authors reported that the treatment possibilities of the method are very large and include the improvement of rheological characteristics of the blood and microcirculation, normalisation of parameters of hormonal, immune, reproductive and many other systems.
… antitoxic, bio-stimulative, immuno-corrective, anti-allergic, antibacterial, antiviral, analgetic, anti-inflammatory
The laser stimulates the immune response of the organism, activates erythrogenesis and improves deformability of erythrocyte membranes, has anti-hypoxic activity on tissues and general antitoxic influence on the organism at different pathological processes. Our laser is used for its bio-stimulative, analgetic, antiallergic, immunocorrective, antitoxic, vasodilative, antiarrhythmic, antibacterial, antihypoxic, spasmolytic, anti-inflammatory and some other properties.
…boost the cellular part of your immunity, decrease concentrations of microbes in the abdomen, activate microcirculation.
The laser activates non-specific mechanisms of anti-infectious immunity. Intensifying of bactericidal activity of serum of the blood and system of the complement, reduction of the degree of C - reactive protein, level of average molecules and toxicity of plasma, increasing the content of IgA, IgM and IgG in the serum of the blood, as well as decreasing of the level of circulating immune complexes are proved. There are studies on boosting effects of the laser on the cellular part of immunity (N. F. Gamaleya et al., 1991). Under influence of the laser, the phagocytic activity of macrophages markedly increases, concentration of microbes in the abdomen of patients decreases, reduction of inflammatory exhibiting of disease, activation of microcirculation are detected. The medical effect of the laser is stipulated by its immuno-corrective activity by normalisation of intercellular relationships within the subpopulation of T-lymphocytes and increasing the amount of immune cells in a blood. It elevates the function activity of B-lymphocytes, strengthens the immune response, reduces the degree of intoxication and as a result improves the general condition of patients (V. S. Sergievskiy et al., 1991).
…increase energy and normalise tissue metabolism, activate ATP–synthesis and energy formation in cells, increase oxidation of energy-carrying molecules.
The laser promotes improving the rheological properties of blood, rising fluidity and activating transport functions. That is accompanied by increasing the oxygen level, as well as decreasing the carbon dioxide partial pressure. The arterio-venous difference by oxygen is enlarged, that testifies the liquidation of a tissue hypoxia and enrichment the oxygenation. It is a sign of normalisation of tissue metabolism. Probably, the basis of activation of oxygen transport function of the laser is the influence on haemoglobin with transforming it in more favourable conformation state. The augmentation of oxygen level improves metabolism of the organism tissues. In addition, the laser irradiation activates the ATP synthesis and energy formation in cells (A. S. Krjuk et al., 1986). Application of IV LBI in cardiology has shown that procedures have analgetic effect, show reliable rising tolerance of patients towards physical tolerance test, elongation of the period of remission. It was proved that the laser reduces aggregation ability of thrombocytes, activates fibrinolysis, which results in peripheral blood flow velocity increasing and tissues oxygenation enriching. The improvement of microcirculation and utilisation of oxygen in tissues as a result of the laser is intimately linked with positive influence on metabolism: higher level of oxidation of energy-carrying molecules of glucose, pyruvate, and other substances.
… unblocking of capillaries, positive pre- and post-surgical operations effects.
The improvement in microcirculation system is also stipulated by vasodilation and change in rheological properties of blood as a result of drop of its viscosity, decrease of aggregation activity of erythrocytes due to changes of their physicochemical properties, in particular rising of negative electric charge. Finally the activation of microcirculation, unblocking of capillaries and collaterals, improvement of tissue trophical activity, normalisation of a nervous excitability take place (N. N. Kapshidze et al., 1993). TSLT is recommended to apply before surgical operations as preparation for intervention, as well as in the postoperative stage, because the laser irradiation of blood has not only analgetic effect, but also spasmolytic and sedative activity.
…regeneration and reparation of cells, incl. inner genital organs.
Our laser procedures have found broad application in obstetrics and gynaecology for activation the blood flow in utero-placental and feto-placental basins, for prophylaxis of the pathologies at delivery, for influence on inflammatory processes of inner genital organs. The laser normalises production of gonadotropins, improves microcirculation, elevates oxygen pressure in blood and in tissues, and so accelerates the process of regeneration and reparation.
…increase functional activity of the hypothalamus and positive effects on the activation of energetic, metabolism, immune and vegetative responses.
In order to explain the generalised and multifactor effects of the laser, its positive influence practically on all tissues and functional systems of the body, clinical effectiveness for the treatment of different diseases, some authors mentioned that the improvement of microcirculation after TSTL is detected in all structures of central nervous system, but this improvement is most active in the hypothalamus, which has highly developed vascular system. The capillaries of a hypothalamus are remarkable for high permeability for macro-molecular proteins, which should even more amplify influence of the irradiated blood to subthalamic nuclei. So it is supposed, that TSLT increases the functional activity of hypothalamus and all limbic system, and as a result the activation of energetic, metabolism, immune and vegetative responses, mobilization of adaptive reserves of an organism is reached.
VIRUS CLINIC #04
RETROVIRUSES of human importance:
1. Deltaretrovirus: Human T-lymphotrophic virus type-1 causing T-cell leukaemia.
2. Spumavirus: Human foamy virus – no disease known
3. Lentivirus: Human immunodeficiency virus type-1 and type-2 causing AIDS and CNS disease.
Common feature of Lentiviruses:
Lentiviruses can infect non-dividing cells.
Lentivirus encode regulatory proteins such as Tat and Rev which regulate viral transcription.
Lentiviruses persist lifelong with ability to integrade into host chromosome and ability to evade host immunity.
Lentiviruses have high mutation rate.
Family: Retroviridae, Size: 80-130 nm, Envelope: Yes, Genome: Nucleus, Disease: Slow (aids, pneumonia, eg), major human: HIV-1 and HIV-2, Capsid symmetry: Icosahedral, Genome: approx. 10 kb, Virus assembly: cytoplasm.
The infection proceeds through at least three stages:
1. Initial infection is rapid viral replication and dissemination, often accompanied by a transient period of disease,
2. Followed by a latent period, during which the virus is brought under immune control and no disease occurs,
3. Finally high level of viral replication resumes later, resulting in disease.
Discovery of human lentiviruses:
First recognised in 1981 with a report of 5 cases of Pneumocystis carinii pneumonia (PCP) in 5 previously healthy men in the Los Angeles area.
At the time even a single case of PCP was unusual and a cluster of several cases signalled that something new and unusual was taking place.
In 1983, Francoise Barre-Sinoussi, Claude Chermann, and Luc Montagnier at the Pasteur-Institute isolated a retrovirus from the lymph node cells of a patient with lymphadenopathy (swollen lymph glands) and called it lymphadenopathy virus.
Next year, Robert gallo’s group at NIH confirmed this finding, linking virus to immunodeficiency syndrome, AIDS. In 1986, a second HIV was isolated (HIV-2) from West Africa.
- Acquired Immunodeficiency Syndrome was first described in 1981.
- HIV-1 isolated in 1984, HIV-2 in 1986
- Enveloped RNA virus, 120 nm in diameter
- HIV-2 shares 40% nucleotide homology with HIV-1
- Gag core proteins – p15, p17, p24
- Pol - p16 (protease), p31 (integrase/endonuclease)
- Env – gp 160 (gp 120, outer membrane; gp41, transmembrane)
- Other regulatory proteins, fe. Tat, Rev, Vif, Nef, Vpr and Vpu
The HIV epidemic:
90% of HIV cases occur in the part of the world with no access to antiretroviral therapy,
Numbers of people dying from AIDS is staggering,
A vaccine for HIV is an urgent global need
Leading infectious causes of Death:
1. acute lower respiratory infections
2. AIDS
3. Diarrhoeal diseases
4. Tuberculosis
5. Malaria
Clinical Feature of HIV infection:
a) Asymptomatic infection
Carrier state that follows initial infection lasting for many years, with a graduate decline in the number of circulation CD4+ T cells. In some cases, infection does not proceed beyond this asymptomatic phase and CD4 counts remain stable.
b) Symptomatic HIV infection and AIDS
Symptoms related to HIV infection develop occurring about 10 – 12 years after initial HIV-1 infection with a decline in circulating CD4 count below 200 cells per micro litre. (Normal count: 800 – 1200)
HIV-1 replication goes on for >10 years, during which time the body has to replace all T cells that have been killed.
This constant requirement to replace billions of T cells is believed to gradually wear out the body’s ability to produce these cells.
Additionally it is known that continous evolution of the HIV genome eventually overwhelms the immune system’s ability to respond.
High virus load is associated with rapid progression of disease.
HIV replication steps:
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Maturation, proteolytic processing of Gag and Gag-Pol
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Binds the next cell using gp120 – CD4 interactions
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Gp42 undergoes conformational change allowing membrane fusion and entry of core into the cell
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Virion core is uncoated and expose viral nucleoprotein complex, which contains MA, RT, IN, Vpr and RNA
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Complex is transported to nucleus
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Genomic RNA is reversed transcribed by RT into partially duplex linear DNA
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IN catalyzes integration of viral DNA into host chromosome and thus completing the viral replication cycle.
(see picture lecture 8a)
Gag encodes internal proteins
Pol encodes RNA genome, reverse transcriptase, integrase, protease
Vpr contain nuclear localisation signal, direct nucleocapsid to nucleus
Nef promotes CD4 degradation, negatively regulates Tat and Rev
Env codes for outer membrane coat
Tat trans-activator of transcription, accelerates viral protein production
Vpu newly synthesized Env are sometimes held in ER through interaction with newly synthesized CD4 (as host are CD4+ cells). Vpu binds CD4 and promotes its CD4 degradation, allowing Env transport to cell surface for viral assembly
Rev promotes full-length viral RNA transport from nucleus to cytoplasms
Vif important for viral maturation, vif-mutant show reduced levels of viral DNA-synthesis.
Env protein(regulation = structural) / Function: codes for outer protein coat gp160, which splits into gp120 and gp41 by protease. Gp120 (550 residue) that binds to CD4 and a co-receptor CCR5 and CXCR4. Binding to co-receptor is dependent on V3 region (variable loop) gp41 (345aa) in viral membrane mediate membrane fusion
Protein Regulation Function
Gag,
structural, encodes internal proteins (MA, CA, NC, p6) required for various
functions as follows
MA,
targets Gag to plasma membrane prior to viral assembly -132
residue – also helps of Gag Env glycoprotein incorporate in
viral particles
CA,
2nd component towards C-terminus, residue (152-231) – primary
function in viral assembly core of virus
NC,
3rd component binds to full length viral RNA and delivers into assembling virion – 55 residue
p6,
comprise the 51 amino acids, binds Vpr and incorporates C-
terminus Vpr in viral assembly, also helps viral of Gag release
Pol,
encodes the HIV core: p7, p9, RNA genome, reverse trans-
scriptase (RT), ribonuclease, integrase (IN), protease (PR)
PR,
PR has proteolytic activity to produce final MA, CA, NC &
p6 from Gag and PR, RT, IN proteins from Pol. Required for
virion maturation into infectious particle.
RT,
Before viral genome can be integrated into host chromosome,
it must be reverse transcribed into dublex DNA. This reaction
is catalyzed by RT. RT is a heterodimer containing 560-
residue subunit (p51) – both contains polymerase domains
IN,
288-residue, following reverse transcription, IN catalyzes a series of reaction
to integrate viral genome into host chromosome. First, IN re-
moves 3’ end nucleotides from each strand of viral DNA. Se-
condly 3’ ends are covalently joined to 5’ end of the target
DNA. Thirdly unpaired nucleotides at viral 5’ end are removed
and ends are joined to the target site 3’ ends. Viral substrate used
for integration is linear DNA containing a complete minus strand
and a discontinous plus strand, which is completed following integration.
TAT,
positive, transactivator of transcription. Can regulatory accelerate viral
protein production of proviral genome several thousand times.
Up-regulates Rev, Nef, and itself. This protein is 88 amino
acids long
Vpu,
positive, 81 residue – newly synthesized Env are sometimes held in ER through interaction with newly synthesized CD4. Vpu binds CD4 and promotes its CD4 degration, allowing Env transport to cell surface for viral assembly. Variation on gene result in decreased release of virions, required for smooth release of virions from infected cells.
Nef,
positive, 206 amino acids – reduces levels of CD4 – Facilitates routing of CD4 from cell surface and golgi to lysosomes p romotes virion release. Also downregulates MHC-I molecules thus protects killing of infected cells by CTL. Nef mutants exhibit decreased rate of viral DNA synthesis following infection. Also negatively regulates Tat and Rev. Inhibits induction of NF-kB, which indicates that NEF may sustain latency period.
Vpr,
weak, 96 amino acids. Following entry, virus is uncoated and nucleoprotein complexes are transported to host cell nucleus by Vpr protein. Vontains NLS (nuclear localization signal) that directs transport to nucleus. Can also induce cell cycle arrest at G2.
Vif,
infectivity, 192 residue protein. Important for mature infectious virion vif-mutant shows reduced level of viral DNA synthesis and altered core structure. Increases infectivity of HIV, thus increased transmission.
Rev,
pos/neg, located in nucleus. Promotes unspliced RNA transport to cytoplasm, thus prevents spliced RNA expression. More Rev, the full-length RNA is present and greater amount of expression of Env proteins. Less Rev, more small, spliced RNA pieces that encodes for regulatory genes. Activate transport of viral mRNA from nucleus into cytoplasm.
Tnv/Tev,
pos/neg, a fusion protein resulting from a frameshift reading the mRNA (mixes up Tat/Env/Rev) and has full functional capacity of both TAT and REV.
Replication:
The first step of infection is the binding of gp120 to the CD4 receptor of the cell, which is followed by penetration and uncoating.
The RNA genome is then reverse transcribed into DNA which is integrated into the cell genome. This is followed by the synthesis and maturation of virus progeny.
Requirement of CD4?
Very specific – only cells that express CD4 allow HIV entry or replication
Tropism in HIV:
Some strains of HIV replicate well in macrophages and are called M-tropic
Some strains of HIV replicate well in T cell lines and are called T-tropic
Some strains of HIV can replicate well in both and are called dual-tropic
Both macrophages and T cells have CD4
HIV-1 envelope protein:
Initially synthesized as 895aa gp160 protein cleaved by cellular protease into:
Gp 120 (550aa), extracellular, that interacts with CD4 on cells
Gp 41 (345) contains transmembrane domain. |
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