Team:Aboa/Human Practices
Human Practices
As our team mostly consists with the students of the Biotechnology unit in the University of Turku, we know the principles of immunoassays and antibody dependent diagnostics quite well, so from day one we decided that the focus of our project would be on them. But we really did not know what antibody dependent diagnostic tests could be used for, outside the research lab. So, we set out to investigate the needs and demands of the people using immunoassays in laboratories and hospitals. Luckily, we live in Turku, where everyone knows one another, and we quickly had connections built up and several people to meet up with.
On this page you can read how we have investigated the needs and demands for immunoassays and how we integrated the results of our investigation into our project!
Interviews with Doctors
In most healthcare systems around the world, doctors are responsible for diagnosing the patient and choosing the right treatment from countless different options. That’s why we decided to interview doctors from the Turku University Hospital and see what kind of demands they have for the sensitivity and accuracy of the diagnostic tests they use, and whether there should be improvements of some kind in the current tests.
We learned that diagnostic laboratory tests are an important part of the patient examination. They provide knowledge about the patient’s condition that could not be acquired in any other way. For example, no one can see if unconsciousness is due to low blood glucose or some drug. The more doctors know about their patient’s condition, the better are the odds that they choose the correct treatment right away - thus improving the prognosis and saving health care resources.
We also learned that there really is a need for better diagnostic tests, especially for point-of-care (POC) tests that could be performed fast and with no need to ship the sample, or the patient, elsewhere. One example of a POC test that needs to be improved is heart specific Troponin tests that indicates heart attack. We encountered this need in almost every conversation we had with doctors.
These interviews confirmed that our project will focus on improving POC tests. You can read the interviews that led us to this project from bellow.
Aku Painilainen is a Medical Doctor specializing in anesthesiology. Before he started his specialization, he worked as a general practitioner in Community health centers and as an Emergency Room (ER) physician in 15 different ER’s and on-call clinics around southern Finland, including Turku University Hospital. As a doctor, he has to order laboratory tests for patient samples in order to diagnose different conditions and to be more certain about his decision.
Our meeting began by us presenting our project to Painilainen, after which the conversation continued by discussing diagnostic point-of-care (POC) -tests in general. He said that POC -tests are becoming more and more commonly used in the healthcare sector, especially in hospital emergency rooms, ambulances and community health centers that do not have their own laboratories.
While discussing the need for more sensitive POC -tests, Painilainen immediately mentioned troponin tests. Troponins are important heart infarct markers, especially if the patient has non-ST elevation myocardial infarction (NSTEMI) that can’t be detected with ECG (Electrocardiogram). According to him, current troponin POC - tests give a qualitative result that tells you if the sample’s troponin concentration is over 50 ng/l - even though the cut-off value is 14 ng/l. So there is certainly room for improvement.
Painilainen told us that in medical school they were taught that current troponin POC- tests are unreliable and that the results they give are merely indicative. There is also a high sensitivity troponin test, but it needs to be performed in a hospital laboratory. According to Painilainen, it may take from 1.5 h to 2 h before he gets the results from the hospital laboratory and that is just time wasted on waiting. Also, in some of the hospitals, the laboratory is not open during the night, so patients need to wait until the morning to have their troponin levels tested with this high sensitivity test.
When asked about needs for other improved POC -tests, Painilainen mentioned Fibrin D-dimer that indicates thrombosis, but as far as he knows that test is unreliable due to the Fibrin D-dimer being quite an unspecific biomarker. He also mentioned that community health centers would benefit from better POC leucocyte -tests. He also brought up a need for POC -tests for brain injuries and explained us that there is quite an intensive ongoing research for biomarkers and tests in University of Turku and Turku University Hospital.
We also discussed the significance of sensitive and reliable POC -tests. According to Painilainen, there would be many benefits to having these kinds of tests, including early diagnosis. In some cases, tests could be performed by paramedics in the ambulance and they would then have better information concerning whether the patient needs to be examined further in a hospital or if it is safe for the patient to seek treatment in a local health center the next day. Another example was from hospital’s ER, where treatments could be initiated faster if diagnosis was confirmed sooner rather than later. Studies have shown that the faster the patient gets through the ER to definitive treatment, the better the prognosis is. Lastly, there would be savings in healthcare expenses, as there would be less work per patient and less time used to get the patient in and out of the hospital.
The meeting with MD Aku Painilainen was very valuable to us. We learned quite a lot about laboratory tests and immunoassays in the health care sector from our teachers and lecturers, but this was the first time we discussed it with someone who uses them to diagnose and treat people. It was very interesting and educational for us to hear what people in the healthcare sector actually want and need in order to be able to work more effectively.
- Riku
Professor Juhani Airaksinen is the Director of Heart Centre in Turku University Hospital (TYKS) and Professor of Cardiology in University of Turku (UTU). He is an internationally respected researcher and he has studied heart diseases longer than the average Team Aboa member has lived. He has also done co-operation with the UTU Biotechnology unit and is very familiar with immunoassays and their use in the medical field, especially with cardiac markers, such as Troponin T and Troponin I.
We started by discussing the clinical relevance of Troponin T/I (Tn) tests and he explained that, in some cases, even the first test can confirm or rule out heart infarct, but generally it is advised to measure the change in blood Tn -levels, especially when the first sample indicates a low concentration. This is due to fact that lots of other diseases and conditions might also raise Tn concentration in blood, such as Sepsis, Renal failure and even running a marathon. This gives rise to a lot of false positive results.
False positives may also be in part due to antibodies cross reacting with skeletal muscle troponin. Prof. Airaksinen said that troponin being released into the blood circulation during a heart attack, while the heart muscle is going through necrosis, is somewhat different than troponin being released in other conditions. This is a widely researched matter at the moment, and hopefully science provides us with better markers in the future.
We also discussed current troponin tests, their clinical use and significance. Prof. Airaksinen told us that in large tertiary centres (like TYKS) point-of-care (POC) tests are not that significant, but in remote area ambulances, hospitals and health centers they are commonly used. He also mentioned that the problem with current POC tests is that the cut-off limit in troponin is lower than the minimum sensitivity of POC tests.
Ideally, the troponin POC test would identify people who have to be treated immediately and/or sent to the hospital for intensive care, while deselecting healthy people who can be sent home or to non-intensive care, thus freeing up the health care resources. Airaksinen also mentioned that almost 50 % of Finns die due to heart attack, and a rapid diagnosis has positive effects on both the short- and long-term prognosis.
Also, the replicability of the test is important, according to Airaksinen. Some variation of the test result is always caused by the sampling process and physiological variations, but every test has its own variation caused by the test itself. A small test variation allows for more reliable detection of even small changes in troponin levels.
One thing that Airaksinen pointed out is that the more sensitive and accurate the laboratory test is, the more confidence it gives to the doctors making decisions based on the laboratory tests. Also, accurate tests provide doctors with better protection from lawsuits, even though in Finland the system is quite different from what it is in the United States where the doctors have to order tests also to protect themselves from lawsuits.
Our discussion with Prof. Juhani Airaksinen was very meaningful. Even though he confirmed a lot of what we have heard before, he also provided us with loads of other things that we had not yet thought of. The most surprising thing was that accuracy and sensitivity can also cause problems if antibodies used in a biosensor are not specific enough against the biomarker of interest.
Interviews with Laboratory personel
To further investigate the current state of the immunoassays, possibilities of our project and the requirements the laboratories have for the new tests, we interviewed people developing new tests and working in large laboratories. And, boy, did we learn a lot!
Even though immunoassays are cheap, they come with certain disadvantages that are driving central laboratories to use the more sensitive, but also more expensive, mass spectrometry. Immunoassays have a future in point-of-care (POC) tests, though, as mass spectrometers are hugely expensive machines! Also, microfluidics has been coming to POC tests for a long time, but it has yet to have its breakthrough as the challenge is to manufacture affordable small and sensitive biosensors.
We also learned that sometimes other methods than immunoassays should be used. Sometimes, the molecule size of the biomarker is too small, as is the case with steroid hormones, to be analyzed with an immunoassay or sometimes other methods are just way more convenient, like PCR in early stage virus infections.
To have a new test method incorporated into a laboratory, it needs to pass a series of standards and laboratory’s internal test verification. If a test is to become part of an automated line, it needs to be easily intgrated into one.
Read more about our meetings with laboratory personnel from bellow!
Tanja Savukoski, PhD is a Clinical Chemist at the Turku University Hospital Laboratory (TYKSLAB). She did her PhD in unit of Biotechnology at University of Turku, and specialized in clinical chemistry at the Helsinki University Hospital Laboratory (HUSLAB). She has also worked as a researcher at the University of Turku, where she studied immunoassays, and especially the heart biomarker troponin.
During the meeting, we began by presenting our project and explained to her shortly what iGEM is all about, after which we began to discuss immunoassays in general. Savukoski told us that immunoassays are experiencing a bit of inflation, and that there are some analytes that in the future will be analyzed with mass-spectrometry, even though it is a more expensive method. However, mass spectrometry is also a more sensitive and specific method for analyzing and detecting small molecules, like vitamin D, cortisol and estradiol in patient samples. She also mentioned that some manufacturers are already selling mass-spectrometers that can be incorporated into automated laboratories, and these will in the future probably become much more popular for this purpose.
But, according to Savukoski, immunoassays are not entirely a thing of the past. On the contrary, they are still being used, and will continue to be used, for detecting larger protein markers and in point-of-care (POC) -tests as well as in places where large centralized automated laboratories are just a dream, like in developing countries. One POC test that she underlined was the troponin test that is used in diagnosing heart infarct. She told us that there are several manufacturers that wish to achieve high-sensitivity POC test for troponin measurement, but so far, it’s yet to be achieved.
When asked about the techniques uses in microfluidics, she answered right away that we must consider those. She continued to explain that microfluidic tests have not yet had their breakthrough, but new products are coming into the market every so often. One of the challenges in microfluidics is manufacturing an antigen binding surface that is dense enough.
Also, Savukoski suggested that we should find out how our test surface could be modified to whitstand sub-optimal storage conditions. In developed countries every Health Center has a fridge where to store POC -testing cartridges and supplies, but that might not be the case in developing countries.
Savukoski made some good points for us that we had not thought of before, like mass- spectrometry becoming a part of automated central laboratories and storage conditions of the test surface being important. She also made a very clear point that high sensitivity POC tests for troponin are currently a number one goal for many manufacturers. All in all, we got a lot of new information about immunoassays, their usage and current trends in development.
- Riku
The Finnish Red Cross Blood Service (FRCBS) handles all the donated blood in Finland. All blood products, like Red Blood Cells and Platelets, used in Finnish Hospitals are provided by them. This makes it important to screen all the donated blood for pathogens. We visited the Finnish Red Cross Blood Service headquarters and met laboratory specialists Susanna Wessberg, Niina Putkuri and Heli Tenkanen. First, they showed us the techniques that FRCBS uses to screen every sample they get, then we discussed about demands that they have towards new tests and, finally, we got a tour of their massive laboratory!
Every day, about 800 people donate blood in Finland and from every donation there are 3 samples taken. That adds up to about 2400 samples analyzed every day, so FRCBS’s laboratory needs to be capable of high throughput, but no errors are allowed. This requires high automation, sample tracking systems and capable people.
They mainly use two different methods for detecting pathogens. PCR techniques detect pathogen DNA or RNA, and, depending on the pathogen, antigen or antibody detection can be used as a detection method. Antigen immunoassays detect pathogen surface antigens, and antibody detecting immunoassays detect whether blood contains human antibodies against a certain pathogen. One reason for using more than one technique is that viruses are not always detectable with just one method. PCR techniques are best suited for detecting an early stage infection, while antigen and antibody assays are more suitable for detecting mid or late stage infections. This is due to the change in virus concentration in the blood as a result of the body’s response to an infection. We learned that people might have severe infections, but because our immune system is so effective at clearing pathogens from the blood circulation, they never experience the symptoms.
We also discussed how new tests are validated and what requirements they need to pass in order to implement in the laboratory. They explained that every test and device they take into use needs to have the European CE ( Conformité Européenne ) marking and must be able to be incorporated into the automated laboratory. After these requirements have been met, they also themselves validate the new test and machine in order to be certain that these perform as required.
Lastly, we got a tour of their automated laboratory, where all the magic happens! We saw the huge automated line that can handle FRCBS’s 2400 samples during the night. The same automation line is in use also during the day, but then it’s used by a private sector laboratory that provides sample analyzing for private, and some public, hospitals. We also saw the place where the blood type (you know, the A+, O- things) of all the 800 daily donations are tested.
During our visit, we learned that one test is not always enough, even if it is more sensitive and has less variation than than any other test! Sometimes, it’s biology and human physiology that intervenes and requires us to use another method of testing. But now we’ve seen the place where all the blood products are handled before they go in use to hospitals. And who knows how many lives that blood saves daily?
- Riku
Integrating issues on the Project
We learned that there is a continuous demand for more accurate and sensitive POC tests, especially for heart infarct where a faster diagnosis leads to better prognosis.
Improving the test specificity by developing new antibodies or finding new markers would require years of research, so we ended up looking for a way to increase the antibody activity in current biosensors, while at the same time keeping them inexpensive. You can take closer look at our solution in our Project Description -page.
