Virsuses: Human Immunodeficiency Syndrome & Acquired Immunodeficiency Syndrome
Outline we may need to save some topic in lecture Origins of HIV based on scientific evidence HIV viral particle Mechanism of infection Transmission Treatment AIDS Prevention Clinical Detection and Diagnosis: you will learn one of these techiques in lab today.
Transmission of HIV
Biological fluids –Blood –Sexual transmission (Semen) –Breast milk –Transplant tissues
Non-transmitting sources of HIV Tears Saliva Mosquito or insects Swimming pool Food handling
Highly Active Antiretroviral Therapy (HAART) Cocktail Therapy
Examples of anti-retroviral drugs Cocktail Drug Mixtures –Protease inhibitors –Non-nucleoside RT Inhibitors (NNRTIs) –Nuleoside/nucleotide RT inhibitors (NRTIs) –* Fusion Inhibitors*Fuzeon –Integrase Inhibitors –portmanteau inhibitor
Fusion Inhibitors block Co-receptors on host cell Gp120/gp 41 on viral particle or
Co-Receptors CCR5 & CXCR4 (fusin) Binds naturally occurring chemokines
Prevention Condoms Clean needles Treatment of pregnant mother with anti-viral drugs Blood screening Abstinence
Acquired Immunodeficiency Disease
Symptoms of AIDS Decrease T cell count Rapid weight loss Recurring fever and dry cough Profound fatigue Swollen lymph glands
Symptoms of AIDS Persistent diarrhea Unusual blemishes on the tongue, mouth, or throat pneumonia memory loss, depression
Acquired Immunodeficiency Syndrome Opportunistic Diseases and cancer pneumonia Kaposi’s Sarcoma
HIV Diagnostic Tests ELISA Indirect evidence of HIV exposure measures
HIV Diagnostic Tests Western Blot PCR Directly measures HIV
Polymerase Chain Reaction Measures proviral DNA within the host DNA
Western Blot Identifies HIV proteins Protein ladder
A diagnostic test for Antibodies to HIV Enzyme Linked Immunosorbent Assay (ELISA) Antibodies
Antibodies are proteins produced by our immune system that are directed against specific antigens.
Antibodies Antigens Immune system Non-self
Now apply these concepts to the diagnostic test known as ELISA to detect antibodies against HIV from a biologic fluid.
The ELISA protocol antigen sample Labelled 2 nd Ab Color inducing substrate
Results POSITIVE ANTI-HIV COLOR CHANGE NEGATIVE ANTI-HIV NO COLOR CHANGE
FDA Approves Saliva OraQuick Rapid Test for HIV-1, HIV-2 Antibodies [March 29, 2004] (similar test is also available for blood samples, see next slides).
OraQuick Rapid Anti-HIV Blood Test minute test Cost app. $15.00
Onto the ELISA lab
For Your Information and Files
Acquired Immunodeficiency Syndrome Normal CD4+ count Normal CD4 + (%) AIDS /mm % <350/mm 3 begin anti-viral treatment <14% serious immune damage
Table 1. For Your personal Information: not for lecture. Antiretroviral Agents AgentTypeDoseMajor Toxicities AZTNRTI300 mg bidnausea, headache, low blood counts ddINRTI mg bid or mg qd (tablet form) diarrhea, pancreatitis, peripheral neuropathy ddCNRTI0.750 mg tiddiarrhea, peripheral neuropathy d4TNRTI30-40 mg bidabnormal liver function tests, peripheral neuropathy 3TCNRTI150 mg bidminor abacavirNRTI300 mg bidhypersensitivity reaction tenofovir NRTI (nucleotide) 300 mg qd nausea, diarrhea, vomiting, flatulence
AZT/3TC (Combivir) NRTIone pill bid (300 mg AZT/150 mg 3TC) see above AZT/3TC/a bacavir (Trizivir) NRTIone pill bid (300 mg AZT/150 mg 3TC/ 300 mg abacavir) see above nevirapineNNRTI200 mg bidrash delavirdineNNRTI400 mg tidrash efavirenzNNRTI600 mg qhsrash, dizziness, impaired concentration, insomnia, abnormal dreams saquinavir (Fortovase) PI1200 mg tiddiarrhea ritonavirPI600 mg bidnausea/vomiting, drug interactions indinavirPI800 mg tidkidney stones nelfinavirPI750 mg tid or 1250 mg bid diarrhea amprenavirPI1200 mg bid nausea/vomiting, diarrhea, rash lopinavir/ri tonavir PIthree capsules bid (133.3 mg lopinavir/33.3 mg ritonavir) diarrhea, nausea, weakness, headache
Experimental drugs are italicized, and approved drugs are in regular, non-italicized type) Brand Name Generic NameAbbreviationExperimental CodePharmaceutical Company FuzeonFuzeon™enfuvirtideENFT-20Trimeris and Hoffmann-La Roche BMS Bristol-Myers Squibb GSK-873,140GlaxoSmithKline PRO-542Progenics Pharmaceuticals SCH-DSchering-Plough Corporation TNX-355Tanox and Biogen Idec UK-427,857Pfizer
Interesting links on HIV –Links to global and US HIV/AIDS statistics –Links to HIV and pregnancy as well as numerous other links including statistics on global epidemic; HIV/AIDS quizzes and treatment. –Links to CDC and a comprehensive fact sheet on HIV transmission
Experimental drugs are italicized, and approved drugs are in regular, non-italicized type) Brand NameGeneric NameAbbreviationExperimental Code Pharmaceutical Company Fuzeon™enfuvirtideENFT-20Trimeris and Hoffmann-La Roche BMS Bristol-Myers Squibb GSK-873,140GlaxoSmithKline PRO-542Progenics Pharmaceuticals SCH-DSchering-Plough Corporation TNX-355Tanox and Biogen Idec UK-427,857Pfizer What are Entry Inhibitors (including Fusion Inhibitors)? Entry inhibitors work by preventing HIV from entering healthy T-cells in the body. They work differently than many of the approved anti-HIV drugs – the protease inhibitors (PIs), the nucleoside reverse transcriptase inhibitors (NRTIs), and the non-nucleoside reverse transcriptase inhibitors (NNRTIs) – which are active against HIV after it has infected a T-cell. Entry inhibitors work by attaching themselves to proteins on the surface of T-cells or proteins on the surface of HIV. In order for HIV to bind to T-cells, the proteins on HIV's outer coat must bind to the proteins on the surface of T-cells. Entry inhibitors prevent this from happening. Some entry inhibitors target the gp120 or gp41 proteins on HIV's surface. Some entry inhibitors target the CD4 protein or the CCR5 or CXCR4 receptors on a T-cell's surface. If entry inhibitors are successful in blocking these proteins, HIV is unable to bind to the surface of T-cells and gain entry into the cells. Only one entry inhibitor has been approved by the U.S. Food and Drug Administration (FDA): Fuzeon™ (T-20). This drug targets the gp41 protein on HIV's surface. Some experimental drugs target proteins on T-cells: BMS targets the gp120 protein, PRO-542 and TNX-355 target the CD4 protein, and SCH-D, GSK-873,140 and UK-427,857 target the CCR5 protein. HIV-positive people who have become resistant to PIs, NRTIs, and NNRTIs will likely benefit from the entry inhibitors because they are a different class of drugs. This is good news for HIV-positive people who have tried and failed many of the currently approved anti-HIV medications. To learn more on how HIV infects a T-cell and begins to create more viruses, and where each class of anti-HIV drugs blocks this process, click on the following lesson link: The HIV Life Cycle (and the targets of each class of anti-HIV drugs) FuzeonBMS GSK-873,140PRO-542SCH-DTNX-355UK-427,857protease inhibitors (PIs)nucleoside reverse transcriptase inhibitors (NRTIs)non-nucleoside reverse transcriptase inhibitors (NNRTIs)FuzeonBMS PRO-542TNX-355 SCH-DGSK-873,140UK-427,857 The HIV Life Cycle (and the targets of each class of anti-HIV drugs)