What is the distribution of desmosine in serum in healthy subjects and patients with lung disease?

Lung function tests has long been an important pillar in lungdisease. Not only
is lung function used for diagnostic purpose, but also for estimating the
prognosis and evaluating the effect of a specific treatment.
These parameters are far from perfect. They are not always specific or
sensitive, and often measure the outcome of a process and not the process
itself, namely the development of lung injury.
A search for new parameters hasn't yet yielded a good alternatives. There is a
need to develop alternative markers such as bio-markers. Desmosine isodesmosine
and are examples of this.

In many lung diseases, the underlying problem is the destruction of alveolar
tissue and loss of elasticity. The most common diseases are COPD and pulmonary
emphysema. Elastin in the lung is formed by cross linking tropo-elastin
(elastin precursor). This process is possible due to (Iso)desmosine. These
proteins are exclusively found in elastin. In patients with COPD / emphysema
the degradation of elastin stands centrally. This proces happens under the
influence of proteases. These proteins are produced by several inflammatory
cells (macrophages / neutrophils / T cells). Secondly, there is a
downregulation of the anti-proteases, whitch have a protective role on the
pulmonary elastin. The overall result is elastin degradation whitch causes
various components in the bloodstream. These includes the (iso) desmosine.

Because lung tissue consist of such a high proportion of elastin, there may be
a role for desmosine in pulmonary medicine. This can be diagnostic,to evaluate
therapy and its prognosis. To this date Investigations that have taken place,
could not give DES a role in daily practice.. This is partly due to the small
study populations that have been used and due to the complexity and costliness
of the laboratory assessment.
In recent years there is lots of advancement in this field. Mass spectrometry
(MS) combined with ultra-pressure liquid chromatography (UPLC), is one of the
most interesting develpments. With UP-MS/MS (iso) desmosine can be measured in
various body fluids. UP-MS/MS gives a good sensitivity and specificity in the
measurement of (iso) desmosine.

In the past mostly desmosine (DES) measurements took place in 24 hour urine.
UP-MS/MS allows accurate measurements in the serum. Correlation between 24-hour
urine DES and plasma DES has been examined in only a small subgroup. Inter-day
variation for 24 hour urine was considered relatively stable with a
coefficient of variation of about 8%. This is, however, for plasma DES.

This study aims to determine the normal distribution of desmosine in a healthy
population and a population of patients with COPD (ranging from GOLD I-IV). In
addition, the inter-day variation and the correlation with 24-hour urinary
desmosine will be determined.

Cross sectional descriptive study

Hematoma caused by vena puncture in the arm.
Possible pulmonary function testing