Replacement of HIV p24 Ag test by a multiplex RT-PCR method for primary screening of blood donors

HIV microarray for the mapping and characterization of HIV-specific antibody responses

We used the microarray technology to develop chips containing a comprehensive set of proteins and peptides covering the proteome of HIV-1 clade C, which is the HIV-1 subtype that causes the majority of infections worldwide. We demonstrate that the HIV microarray allows simultaneous, sensitive and specific detection of antibody responses for the major immunoglobulin classes (IgG, IgA, IgM, IgE) and subclasses (IgG1-4) with minute amounts of serum samples towards a large number of HIV antigens and peptides. Furthermore, we show that the HIV chip can be used for the monitoring of antibody responses during the course of the disease and during treatment. The HIV microarray should be useful to study antibody responses to multiple HIV antigens and epitopes in HIV-infected patients to explore pathomechanisms of the disease, for diagnosis and for monitoring of treatment and of vaccine trials.

Primary screening of blood donors by nat testing for HCV-RNA: development of an "in-house" method and results

An "in-house" RT-PCR method was developed that allows the simultaneous detection of the RNA of the Hepatitis C Virus (HCV) and an artificial RNA employed as an external control. Samples were analyzed in pools of 6-12 donations, each donation included in two pools, one horizontal and one vertical, permitting the immediate identification of a reactive donation, obviating the need for pool dismembering. The whole process took 6-8 hours per day and results were issued in parallel to serology. The method was shown to detect all six HCV genotypes and a sensitivity of 500 IU/mL was achieved (95% hit rate). Until July 2005, 139,678 donations were tested and 315 (0.23%) were found reactive for HCV-RNA. Except for five false-positives, all 310 presented the corresponding antibody as well, so the yield of NAT-only donations was zero, presenting a specificity of 99.83%. Detection of a window period donation, in the population studied, will probably demand testing of a larger number of donations. International experience is showing a rate of 1:200,000 - 1:500,000 of isolated HCV-RNA reactive donations.