'ORGAN-ON-A-CHIP' technology could be the future

A research team at the Wyss Institute for Biologically Inspired Engineering at Harvard University have used their new ‘organ-on-a-chip’ technology to develop a model of the human airway so that diseases such as COPD can be studied outside of the human body to allow researchers to gain new insights into the disease mechanisms, identify biomarkers and test new drugs.
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Diseases such as COPD and asthma are inflammatory reactions in the lungs whether to smoking, inhaled particles or bacterial/viral infections. It is already known that many of the disease processes occur in the alveoli however much less is known about how inflammation starts off these reactions and why these processes react in the way that they do. For example the reason why the body recruits white blood cells and the build-up of mucus, both of which compromises the patient’s lungs or the cause and reasoning behind exacerbations.
A new microfluidic model of the lung has been created of the lung’s small airways made with chips lined with cells from both normal donors and diseased patients. This model is like looking inside an actual patient and “recapitulates critical features of asthma and COPD with unprecedented fidelity and detail” explains Donald Ingber. Now with this micro-engineered human lung small airway lung inflammatory diseases over several weeks can be studied in order to gain better insight into disease mechanisms, as well as screen for new therapeutic drugs.
This device closely mimics the 3D cellular architecture of an actual human small airway and contains fully matured human small airway epithelium with different cell types and channels containing all the components that you have in your lungs including white blood cells and nutrients. The device can keep itself ‘alive’ for a few weeks before starting to deteriorate. Inflammatory situations such as asthma and COPD can be simulated by adding an asthma-inducing immune factor or by setting up the system with lung epithelial cells from a COPD patient and then researchers can observe the different ways that the airways react in different situations. In both cases, the team was not only able to observe highly disease- and cell type-specific changes but could also exacerbate them with agents simulating viral or bacterial infection.
Demand for such a device is high due to the fact that the inflammatory response is so complex and internalised that it cannot be adequately studied in humans or animals and there are no known drugs that can stop and start the inflammation processes so that you could potentially get a snap-shot of what was going on.
This new organ-on-a-chip technology has provided researchers with a window on a molecular scale to be able to observe the activities of living human tissue and allows them to break down the processes and interactions of specific cell types and immune system components so as to understand why the diseases progress in the way they do and ideas on how this could be prevented based on the interactions between the lung tissue and the immune system, whether this be by manipulating the immune system response or by developing new drugs to counteract the effects.
“This novel ability to build small airway chips with cells from individual patients with diseases like COPD positions us and others now to investigate the effects of genetic variability, specific immune cell populations, pharmaceutical candidates and even pandemic viruses in an entirely new and more personalized way; one that will hopefully increase the likelihood of success of future therapeutics,” said Ingber.
References: http://medicalxpress.com

ACOS – what does that mean?

Asthma and COPD are both common lung diseases with very similar symptoms. Doctors have long had difficulty in diagnosing a patient when they presented with respiratory symptoms as to which category the patient falls into. Usually asthma is more likely in younger patients and COPD in older patients. However the mechanisms behind the symptoms for asthma and COPD are different and it is likely that 15%-25% of patients with obstructive lung disease actually suffer from both conditions simultaneously. When both of these occur in the same patient it is now known as Asthma COPD Overlap Syndrome or ACOS. Awareness is increasing but it is agreed that patients with ACOS suffer more frequent exacerbations, have a poorer quality of life, experience a more rapid decline in lung function, have a higher mortality rate and consume a disproprtionate amount of healthcare resources compared with patients who suffer from Asthma or COPD alone. However distinguishing ACOS from asthma or COPD is still problematic.

Asthma is defined as a disease characterized by chronic inflammation of the airways. With patients having a history of respiratory symptoms such as wheezing, shortness of breath, chest tightness and a cough. These symptoms can vary over time and in intensity.

COPD is defined as a common and preventable disease, caused by chronic exposure to damaging gases or particles such as smoking. This causes chronic inflammation in the airways and lungs which is also progressive.

ACOS is defined as the patient suffering limited lung airflow with several symptoms that are usually associated with either asthma or COPD. Therefore if you have symptoms from both categories then you can be diagnosed with ACOS.
Unfortunately research on ACOS is limited as most research trials investigating COPD have excluded patients with asthma and vice-versa and also excluded those that presented with both. Also many patients have been misdiagnosed with asthma when in fact they may have COPD or ACOS.

So what is the difference?
All three conditions are chronic diseases and all patients will complain of a cough, dyspnea and wheezing.
Asthma and ACOS share the feeling of a tight chest.
Asthma patients tend to never have had smoked.
COPD and ACOS patients tend to have been exposed to burning fossil fuels, gases or have smoked.
ACOS may be diagnosed in patients that have had long-standing asthma or have had airway remodelling.
COPD and ACOS is usually diagnosed in patients older than forty although ACOS patients usually have had symptoms earlier in life in one form or another, whereas asthma is usually found in patients younger than 40 years of age. Asthma can manifest in childhood, fade away and then may reappear in adulthood at a later date.
Asthma symptoms tend to vary day to day and occur more often at night and linked to triggers such as pollen and dust and exercise. The symptoms also respond well to the right medication and treatment.
ACOS and COPD symptoms tend to be more persistent, improve less dramatically with treatment and progressively get worse.
All three diseases suffer exacerbations but patients with ACOS suffer them three times as frequently and much more severely compared to asthma or COPD alone.
Patients with long-standing asthma may begin to suffer with airway-remodelling which results in incomplete reversibility of airflow and the patient can begin to look more like someone with COPD.
With all these conflicting symptoms which may fall into multiple categories it is still a long and complicated process for a doctor to be able to diagnose their patient properly but once your GP has pieced together all your symptoms, history since a child and performed respiratory tests they should be able to place you in the correct category and treat your accurately.
ACOS is still a fairly newly recognised disease but it has allowed a new understanding of the interplay of asthma and COPD and new research topics are being investigated to aid in understanding all three diseases more accurately.
References: http://www.rtmagazine.com and http://www.goldcopd.org

The dangers of summer

Whatever stage your respiratory disease may be at, preventing flare-ups is highly important to ensure you stay as healthy as possible and to keep your breathing as easy as possible. This means you need to be aware of the triggers and eliminating any exposure to cigarette smoke, fire smoke, dust, chemicals, excessive wind and pollution. Breathing can also be difficult at temperatures around or below freezing, above 90 degrees F, or on days with high humidity, ozone levels or pollen counts.

Many patients have a component of asthma and some prefer warm, dry climates whereas others may prefer more humid environments.
Extreme hot or cold conditions can put stress on the entire body. In order to maintain a constant body temperature, you exert additional energy to warm or cool it down. This additional energy requirement also increases the amount of oxygen that your body is using. Breathing hot or cold air can also have a drying or irritating effect on the airway causing bronchospasm (contraction of the smooth muscle that surrounds the airway). This decreases the size of the airway and makes it more difficult to get the air in and out of the lung, increasing shortness of breath.
In general most patients find that they prefer minimal humidity levels of about 40%. This is also true of indoor humidity levels which can be difficult to maintain throughout the year, if it is a hot summer or a cold winter with the heating on. You can purchase a humidifier that works with your heating system or independent units for single rooms. De-humidifiers can also be purchased to help lower the humidity in certain rooms.
High indoor humidity is often also the source of mould growth in the home which is another trigger, as well as an increase in common indoor air pollutants like dust mites, cockroaches, bacteria and viruses. Also as humidity increases, the density of the air increases. This more dense air creates more resistance to airflow in the airway, resulting in an increased work of breathing (i.e. more shortness of breath).
Look out for common signs of high humidity:
•    flooding or rainwater leaks from the roof or basement/crawl space
•    poorly connected pipes or leaky pipes under sinks or in showers
•    carpet that remains damp
•    poorly ventilated bathrooms and kitchens
•    condensation build-up from humidifiers and dehumidifiers, air conditioners, and drip pans under refrigerators/freezers
Here are some helpful pointers for when it is hot, although many are applicable to other weather conditions as well:
1.    Drink plenty of fluids, fairly obvious for Australians, but please take into account if you have a fluid restriction.
2.    Wear appropriate clothing and sunscreen.
3.    Plan your activities carefully. Try to organise your activities or exercise for the coolest times of the day – early in the morning, or in the evening. When driving, park in shady areas if possible, and choose places to go that are air conditioned. Place sun protectors in your car when it is parked.
4.    Keep cool, indoors. Use your air-conditioner if you have one and remember you do not need it to be freezing cold. A second benefit of the air conditioner is that it removes a great deal of humidity from the air as it cools it. If an air conditioner is not available, use fans and open windows to circulate the air during hot days. Special programmes are available in many places.
5.    Use the buddy system. This means making sure that someone contacts you at least twice a day to check that you are OK.
6.    Avoid rigorous exercise or excess activity.
7.    Take your medications as directed.
8.    Pay attention to weather reports.
References: www.healthline.com and http://lungfoundation.com and https://rotech.com