Analysis on the S100 protein ( a marker associated with brain injuries ) - Causes, Symptoms and Treatment .MF .
S-100 is a specific protein astrocytic glial cells capable of binding calcium, from the pier.mass of 21,000 Da.The protein was first identified in 1965 by B. W. Moore and got its name from the solubility in 100% ammonium sulphate.It consists of two subunits - a and p.S-100 (Pβ) is present in high concentration in glial cells and Schwann (lemmotsitah), S-100 (PF), - in glial cells, S-100 (aa) - in striated muscle, liver, and kidney.Protein is metabolized by the kidneys, its biological half-life time of 2 hours astroglial cells -. It is the most numerous cells in the brain tissue.They form a three-dimensional network, which is the reference framework for the neurons.Commercially available kits allow to determine the forms of the protein S-100 (RR) and S-100 (PF), i.e.useful for the diagnosis of cerebral tissue injury.In recent years, determination of the protein are increasingly used clinically as a marker of tissue damage in the brain cerebral circulatory disorders.Patients with cerebral hemorrhage S-100
S-100 protein is released into the blood in patients undergoing surgery with cardiopulmonary bypass.Peak concentrations falls on the end of extracorporeal circulation and then decreases in uncomplicated cases.In patients with brain complications protein recovery continued in the postoperative period.S-100 level greater than 0.5 mg / L after 2 days after cardiac surgery indicates the presence of the patient's neurological complications.
S-100 - Marker potential damage to the brain, a marker of malignant melanoma.
family proteins S100 (by now known to be at least 25 representatives: S100A1 - S100A18, trichohylin, fillagrin, repetin, S100B, S100G, S100P, S100Z) - small calcium-binding dimeric proteins with MWabout 10.5 kDa which are present only in vertebrates.S100 proteins are the largest subgroup of the so-called «EF-hand» calcium binding proteins (for calcium-binding site structure: helix E - loop - helix F), which, for example, also include calmodulin and troponin C. S100 name has been given by itsfirst description solubility (solubility) of 100% saturated ammonium sulfate.S100 proteins can form both homo- and heterodimers, besides Ca2 + binding also Zn2 + and Cu2 + .. Capture ions changes the spatial organization of protein S100 and allows communication with various protein - targets their biological effect (documented more than 90 potential target proteins).
Representatives of S100 proteins expressed exhibit tissue-specific expression and kletochnospetsifichnuyu.They are involved in various processes - reduction, mobility, cell growth and differentiation, cell cycle progression, transcription, cell membrane organization and dynamics of the cytoskeleton, the cell from oxidative damage protection, phosphorylation, secretion.It is assumed that the S100 proteins serve as intracellular and extracellular functions, some S100 proteins secreted cytokines and operate similarly.S100Β, which is produced mainly brain astrocytes, a marker of astroglial activation, mediates its effects via interaction with the RAGE (receptor for advanced glycation end products - receptor glycosylation end products).It is shown that S100Β exhibits neurotrophic activity at physiological concentrations and neurotoxic at high concentration.Different forms of cancer exhibit a pronounced change S100 products.Increased secretion S100Β characteristic of malignant melanoma.S100 - RAGE interaction plays an important role in inflammation and cancer communication, the survival of tumor cells and cancer progression.Clinical interest in the S100 is associated with the use of it as a marker of brain damage due to traumatic brain injury, Alzheimer's disease (S100Β, released from the necrotic tissue may exacerbate neurodegeneration by S100Β-induced apoptosis), subarachnoid hemorrhage, stroke and other neurological disorders;monitoring malignant melanoma and other neoplastic diseases and inflammatory diseases.
test quantifying S100 (COBAS, Roche Elecsys 1010) aims to identify and dimers S100A1B S100BB.S100A1 and S100B (functional proteins can be represented as homo- or heterodimers) are expressed predominantly by cells of the central nervous system, mainly, astroglia, but are also produced in melanoma cells, and to some extent in other tissues.The test can be used to monitor and control treatment, early detection of metastasis and recurrence (but not a diagnosis!) In patients with malignant melanoma and for integrated assessment of patients with suspected brain damage.
Melanoma. secretion S100 elevated in patients suffering from malignant melanoma (especially in stages II, III and IV), S100 levels correlate with the progression of the tumor, stage of disease and can be used to forecast, detection of recurrence and metastasis (non-primary diagnosis).Exceeding a threshold test by monitoring the treatment of melanoma patients can be expected, on average, in% - patients without evidence of disease - 5.5%;with regional metastases - 12.5%;metastases in the skin / distant lymph nodes - in 47.6%;Distant / visceral metastases - in 42.9% (based on the results of follow-up).In the control group of healthy people above that level observed in 4.9% (95% confidence interval).
In case of high-level research is recommended S100 is repeated in order to avoid false positive results and conduct the relevant tomographic studies to improve diagnostic accuracy.
Adult patients with a potential brain damage. level S100 increases in the cerebrospinal fluid and is released into the blood in different clinical situations.Measurement S100 neurological disorders compared c measurement of CRP in systemic inflammation.S100 may be found in patients with brain injuries of various origin, including traumatic injury or stroke.
after stroke S100 growth begins during the first 8 hours, an increase is maintained for 72 hours, the S100 concentration correlates with the amount of damage, and neurological effects of stroke.Increasing S100 after spontaneous subarachnoid hemorrhage correlates with the severity of disease (level above 0.3 mg / L is associated with unfavorable course). Traumatic brain injury S100 accompanied by increasing levels in the cerebrospinal fluid and serum.
When comparing the concentration of S100 results tomography demonstrated a high negative predictive test value (no damage as a result of imaging at otritsitelnom result S100) - 99 - 100%, but low positive predictive value (damage on the CT scan of the brain with the results of the S100 above the threshold) -9 - 13%.The sensitivity of 96.5 - 100%, specificity of 30 - 35% confidence interval 95%.At moderate traumatic brain injury and S100A1B S100BB growth can be observed in 31% and 48% of patients with no visible signs of cognitive impairment.The indicator can not be regarded as a reliable prediction of long-term neurological outcomes in such cases, especially in children.
should carefully interpret the results, given the opportunity to influence changes in the blood-brain barrier integrity.Early release of S100 may be the result of mechanical damage during separation barrier or hematological activation S100B expression in brain involvement in systemic inflammatory response.Potentially possible extracerebral sources of S100B (chondrocytes, adipocytes).Growth S100 (& gt; 1,5 mg / l) after cardiac arrest and subsequent resuscitation reflects the higher risk of severe neurological consequences.
Indications analysis on the S-100 protein:
- flow Monitoring and control treatment success
malignant melanoma, the early detection of recurrence and metastasis.
- As an additional test in conjunction with survey
potential damage of the brain (including
traumatic brain injury, stroke) for an overall evaluation and prognosis
protein content rate of 100 S-
serum normally at least 0.105 - 0.2 g / l;
in cerebrospinal fluid - less than 5 mg / l.
Explanation of results of analyzes on the S-100 protein:
Please note: measurement S100 concentration may vary considerably, depending on the testing procedure, the results obtained by different methods can not be directly compared with each other, it may cause misinterpretation.If necessary, change S100 test procedure during serial monitoring of the comparability of the results parallel measurement of two methods should be confirmed.
Units: ug / l.
Reference Range: & lt;0.105 g / l (95% of healthy people without clear evidence of any pathology).
Increased protein S-100 in the serum and CSF protein
Increase S-100 in the serum and cerebrospinal fluid (CSF) in the cerebral circulatory disorders caused by the activation of microglia.In the early phase of cerebral infarction microglial cells in the peri-zone express proteins S-100 family, and actively proliferate, and the proteins expressed by no more than 3 days after infarction.This suggests that activation of microglial population is constant early response to ischemia of brain tissue and can be used as an early marker of damage.
oncology: malignant melanoma (correlated with the stage of the disease);
- metabolic brain damage;
- traumatic brain injury;
- spontaneous subarachnoid hemorrhage;
- Alzheimer's disease;
- multiple sclerosis (level fluctuations);
- systemic lupus erythematosus (a neuropsychiatric involvement - organic brain syndrome, convulsions, cardiovascular incidents, psychosis);
- hepatic encephalopathy;
- bipolar disorder during exacerbations, but not in remission;
- neurological damage after cardiac arrest and subsequent resuscitation;
physiological conditions: intense physical training
measurement S100 concentration may vary considerably, depending on the testing procedure, the results obtained by different methods can not be directly compared with each other, it may cause misinterpretation.If necessary, change S100 test procedure during serial monitoring of the comparability of the results parallel measurement of two methods should be confirmed.ug / L.Reference Range: & lt;0.105 g / l (95% of healthy people without clear evidence of any pathology).malignant melanoma (correlated with the stage of the disease);intense physical exercise.