Incident light fluorescence microscopy is growing rapidly in importance as an investigational tool in the fields of medical and biological research. All photomicrographs in this gallery were taken with Olympus microscopes employing UIS optics and a PM-30 automatic camera system.

The specimen is human lympocytes grown in tissue culture that have been infected with HIV and stained using FITC as the fluorophore. Photomicrographs were recorded utilizing a UPL 40x fluorite objective coupled to a NIB dichroic filter combination. A 3.3x projection photo eyepiece was used to transfer light from the intermediate image plane to the photographic emulsion.

It is now firmly established that the deadly Acquired Immuno-Deficiency Syndrome (AIDS) is caused in humans by a retrovirus termed Human Immunodeficiency Virus (HIV). There is no known cure for this disease, although several agents have been found to be efficacious in treatment of the symptoms. In this respect, 3'-azidothymidine (also known as AZT, Retrovir® and Zidovudine) is probably the most effective anti-AIDS medication developed to date. During initial clinical trials using a double-blind placebo, the treated study population displayed a fivefold diminution in mortality rates.

It was therefore deemed medically unethical to continue withholding the drug from patients receiving the placebo and the trial was halted. The drug is phosphorylated in vivo to the triphosphate analog, which is mistaken for thymidine triphosphate by the viral-specific DNA replicating enzyme reverse transcriptase. Subsequently, the azido analog is incorporated into the DNA transcript of viral RNA and causes premature chain termination, thus preventing integration of viral double stranded DNA into the host genome. The header image of AZT crystallites represents a genuine image of hope for a cure from this deadly plague.

Recently, several additional drugs have been approved for use against AIDS. The most promising are the di-deoxyribonucleoside derivatives, 2',3'-dideoxycytidine and 2',3'-dideoxyinosine. These drugs, when used by themselves or in combination with AZT, offer suppression of symptoms in patents that are resistant to AZT. Even newer drugs are constantly being tested and one day, there may actually be a cure for this tragic virus.