Correlation between Sequencing Results from Liquid Plasma and Dried Plasma Spot (DPS) for Determination of HIV Type 1 Non-B Subtypes

Background: The blotting paper is an alternative to the collection of blood in the tubes for analysis, especially in the field of Human Immunodeficiency Virus infection. This technique allows to easily send the collected samples to specialized laboratories while limiting the stresses of storage and transport. Objective: The objective of this study was to compare the results of sequencing performed on liquid plasma and Dried Plasma Spot (DPS) for the variants of HIV-1 non-B. Methodology: Fifty subjects diagnosed positive for HIV Type 1 using the Rapid Screening Tests voluntarily participated in this study. Two hundred microliters of plasma are deposited on blotting paper Whatman 903 and 500 μl in a micro tube. RNA was extracted from 140 μl of plasma fluid and from a piece of DPS of 5 mm of diameter using the QIAamp RNA Mini Kit QIAGEN. After extraction, the Viral Load (VL) was performed on each sample of liquid plasma. A Reverse Transcription PCR and Nested PCR were used to amplify the regions of interest on the Protease and Reverse Transcriptase for subsequent sequencing. Results: Protease and Reverse Transcriptase were amplified and sequenced respectively for 44 (88%) and 48 (96%) with the liquid plasma samples and 40 (80%) and 45 (90%) with the DPS. The results of Viral Loads were in the range of 2.5 log₁₀ and 6.5 log₁₀. The results of sequencing are comparable for plasma samples and DPS. The correlation coefficient (R²) between the two methods is good (R² = 0.903, p < 0.001). Conclusion: Liquid Plasma and Dried Plasma Spot give highly correlated results for sequencing strains of HIV type 1 non-B.