Bulletin Spring‧Summer 1994

Above right: Prof. K.N. Lai Above left: Dr. John S.L. Tarn Below: Dr. Philip K.T. Li Prof. KM Lai obtained his MB BS from the University of Hong Kong in 1975, and qualified as a Member of the Royal College of Physicians (UK) in 1980. He is a Fellow of the Royal Colleges of Physicians (London, Edinburgh, Glasgow), the Royal Australasian College of Physicians, and the American College of Physicians. His research on diseases of the kidney led to the award of an MD from the University of Hong Kong in 1983 and a D.Sc. in 1994. Prof Lai joined CUHK in 1983, and was promoted to professor of medicine (nephrology) in 1992. His co-investigators are DR. Philip K.T. Li and Dr. John S.L.. Tam. Dr. Li is a senior medical officer at Prince of Wales Hospital and an honorary lecturer in medicine at CUHK. Dr. Tam is a senior lecturer in microbiology at CUHK. Using PCR techniques to detect mRNA of the hepatitis virus in kidney biopsies from patients. Lane 2 is a positive control of the relevant RNA; it is clear that the same RNA is detected in biopsies located in lanes 5, 6, 7, and 8. to the kidney. But RNA or mRNA will stay put after they have performed their duty to transfer DNA information. So the site where they are found will definitely be the site where the vims is replicated. So the investigators set out to look for RNA and mRNA. Preliminary Results After careful research and study, Prof. Lai's team has been able to demonstrate the presence of immune complexes related to hepatitis B e antigen (HBeAg) in the diseased glomeruli. DNA of the hepatitis B vims has also been found i n the nearby renal tubules, where urine is concentrated. However, the amount of RNA found is extremely small and cannot be detected directly. Normally, RNA breeds DNA. Through a technique called reverse transcription, researchers can synthesize small copies of DNA out of the small quantity of RNA found. And through polymerase chain reaction triggered by suitable enzymes, this small quantity of DNA can multiply about 10,000 fold to produce a copious amount, from which the presence or absence of RNA can be detected chemically. Through such amechanism researchers successfully proved the presence of RNA and mRNA of the hepatitis B vims in the kidney. The finding suggests that the vims replicates in the tubules of the kidney. The HBeAg that is then shed into the blood circulation induces antibody formation. The chemical complex formed by the HBeAg, its antibody, and the vims circulate in the blood and are finally trapped by the glomeruli. The trapping of the complexes leads to the thickening of basement membranes and local inflammation. Equipped with the new knowledge they have just discovered, Prof. Lai and his colleagues have now set out to study the role of hepatitis B virus in hepatitis B carrier patients with immunoglobulin A (IgA) nephropathy. Research Projects 18