Scarlette Abbou, an engineer at CNRS, explained her lab’s work: “CD4 T-cells – among others – act as reservoirs for HIV, and are established during the earliest stage of infection. These latent reservoirs are able to survive antiretroviral therapy (ART), which allows infected cells to become reactivated and produce HIV after treatment is halted, or if resistance develops. Our team is looking at all the factors that contribute to the survival of the virus in these circumstances, which is really important for the advancement of new treatments.”

Supporting longitudinal HIV studies

The lab has been working with a cohort of HIV-positive patients, followed since the 1990s, monitoring their therapies and disease progression. The VOYAGER adjustable tip spacing pipette has become crucial to this work, as it supports the large screens of multiple patient samples necessary for analysis. Scarlette continued: “One of the things that we look at is the establishment and the dynamic of the HIV reservoir through the study of resistance mutations. We receive blood samples from the patient and extract both the CD4 T-cells and genomic DNA from the host. We perform PCR on the provirus – virus genome that is integrated into the DNA of a host cell – and then analyze the PCR products by running the samples on a gel to see the size of the fragments, and whether they are truncated or complete (around 10 kb in length). After gel electrophoresis, we then perform purification of the PCR products and sequencing.”

Accurately process large samples numbers

“Our cohort consists of around a dozen patients, and screening multiple samples for each individual is a lot of work. We often end up sorting around a million cells from a blood sample. To be sure we are amplifying an individual provirus, we perform limiting dilution – or digital – PCR, which means preparing up to 20 PCR plates at a time for each patient. When loading these samples onto a gel, we need to pipette from the 96 well plate to the gel. A fixed spacing multichannel pipette wouldn’t allow us to transfer multiple samples at once, as the wells in the gel are much closer together than those in the plate, so we originally had to process all of these samples manually one by one. This took a lot of time, especially as it’s important to be careful not to tear the gel.”

“The amount of time it was taking to process large number of samples was a big problem. We contacted several companies to see if they provided electronic pipettes with automatically adjustable tip spacing – and that’s how we came to find INTEGRA! A representative from the company visited us and brought a few different pipettes to try. I instantly liked the VOYAGER; it was really easy to use and control using the different programs. We bought two 8 channel VOYAGERs a couple of years ago and were immediately happy with how they improved the workflow! The VOYAGER reduces the time to transfer samples from a 96 well plate into a gel from around 40 minutes to five minutes or less, which is fantastic when you have multiple plates for several different patients to process! I’ve also noticed a significant improvement in accuracy, as I’m not having to pipette each well individually, so I don’t lose where I am in the wells and there’s no chance of making mistakes. Having the two different volume pipette sizes – 50 and 125 µl – gives us added flexibility for different experiments too.”

Added flexibility for different workflows

“The VOYAGER has made a massive difference to the lab; various colleagues have now seen how it can benefit their work and have been using it for their own experiments. For instance, one of my colleagues is performing qPCR using 384 well plates, and was struggling to pipette between the small wells of that plate and other labware formats. Now, we have to take in turns to use it! It’s amazing though, as it really is saving everyone’s time and frees us up for other experiments. It’s so much quicker to process the samples now, so I have much more time to analyze my results or start preparing my next gel or round of PCR.”

Additional features and great ergonomics

“I really like how the pipette attaches to INTEGRA’s GripTips – it’s incredibly easy, and with a simple push you feel like the tips are really securely attached and that you’ll have no problems with your aspiration or dispensing. You can even adjust the aspiration speed to avoid introducing any bubbles. It’s amazing being able to securely attach multiple tips like this and have confidence that they won’t leak or fall off in the middle of an experiment, which means there’s no chance of losing samples or contaminating other wells. I can quickly attach all eight tips, set the spacing, and get stuck into my experiments! I also love that the tips come in boxes of 384, this means we save lab space as there are so many tips in a box, and it’s more environmentally friendly as there’s less plastic. INTEGRA’s multichannel reagent reservoirs are great for this too, as they are packaged in stacks of 50 reservoirs, and nest inside each other to save space. Each reservoir then just fits easily into a reusable base.”

“The VOYAGER really has enabled my research and allowed me to get from experiment to result so much quicker. An electronic multichannel pipette makes pipetting this large number of samples really easy, and the VOYAGER is particularly comfortable to use; I love the shape of it. Plus, the sound the pipette makes at the end of the program to let you know you’re done is an excellent finishing touch! It makes me feel like it’s a job well done – it’s perfect.”

Further reading:

• 40 years of HIV research: What have we achieved and where are we going?
• Scientists at CNRS using INTEGRA’s VOYAGER to speed up their HIV research