Establishment of a Pcr Technique for Determination of Htlv-1 Infection in Paraffin-Embedded Tissues

HTLV-1 , the first known human retrovirus belongs to oncovirus subfamily of retroviruses. The major characteristic of HTLV-1 is its highly restricted geographic prevalence. Northern part of Khorasan is an endemic region of HTLV-1 infection. Epidemiological studies can help in designing preventive programs for HTLV-1 infection. The aim of this study was the establishment of a PCR technique for determination of HTLV-1 infection in paraffin-embedded tissues.

In this experimental laboratory study for establishment of a technique, PCR was initially optimized using Beta-actin primers on various formalin fixed paraffin-embedded tissues from liver, spleen, skin and lymph nodes. The optimized concentration of Mgcl2 was 2mm, primer was 8 pmol. Optimized concentration of DNA was different according to the kind of tissue. HTLV-1 infection was determined by applying tax, pol, env and LTR primers on 50 paraffin-embedded lymph node tissues . The reporoducibility of this technique was shown for skin and lymph node tissues infected with HTLV-1. Resuls: In 50 lymph node tissues, one case with pathologic diagnosis of NHL was positive with all 5 sets of primers (tax, Pol, env and LTR primers) and the other case was positive with only two sets of tax primers but was negative with pol, env and LTR primers. The prevalence of infection was 2% among lymph node specimens. (1 of 50 specimens ) and if the second case is considered, the prevalence would be 4%.

Comparison of the results of this study with another study on blood specimens (seroprevalence2.3%) was not statistically significant thus confirming the results of one another. (P=0.883)