Maailmassa etsitään biomarkkereita aivotraumojen diagnostisiin ja monitoriointitarpeisiin .

S100-proteiiniperheen S100B on eräs biomarkkeri, mutta se ei ole  spesifinen keskushermoston  sisäisille vaurioille. Duodecim 7/2019 kirjoittaa aiheesta
"Parempaa aivovammapotilaiden diagnostiikkaa ja hoitoa  verikokeen avulla?"
Vuonna 2013 skandinaavinen neurotraumakomitea julkaisi ensimmäisen aivovammojen hoitosuosituksen, joka integroi aivovammapotilaan kliiniseen arviointiin  biomarkkerin. kyseinen suositus sisältää hermotukisoluissa ( glia)  ekspressoituvan S100B-proteiinin määrityksen osana pienen riskin lievän aivovamman saaneen potilaan kuvantamistarpeen arviointia". Kyseisen suosituksen on raportoitu vähentävän sekä diagnostiikkakustannuksia, että pään tietokonetomografioiden määrää".  (Niistä suurin osa on ilman löydöstä ja  antaa jonisoivaa säteilyä joka kertyessään  nostaa syöpäriskiä, joten turhia kuvauksia tulisi välttää ja kuvaustarve tulisi  varmistaa  verikokeista  lievissä  aivovammoissa - ei edes  lumbaalipunktiosta, joka on invasiivinen diagnostinen menetelmä. Lieviä  aivovammoja tulee  lisääntyvässä määrin  jo urheilun alueelta, esim jääkiekkoilusta).
 " Mainitun  biomarkkerin S100B   käyttöä rajoittaa kuitenkin keskushermoston ulkopuolinen ekspressio, jonka vuosi merkkiaine reagoi muun muassa tuki- ja liikuntaelimistön vammoihin. S100B ei sovellu itsenäiseksi testiksi aivovammoihin, vaan sitä on käytettävä yhdessä kliinsiten löydösten kansas, kuten on todettu skandinaavisessa suosituksessa.  toistaiseksi tämän hoitosuosituksen luotettavuudesta on vielä vähän tutkimusnäyttöä".
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Ensinnäkin vähän  S100-proteiiniperheestä Pub med haku  "S100 functions"(2013).
https://www.ncbi.nlm.nih.gov/pubmed/22834835

Curr Mol Med. 2013 Jan;13(1):24-57. tämä on laaja artikkeli kaiksita S100 proteiineista ja otan siitä sitaatin vain tästä S100B:   (Jatkan toiseen otsikkoon   Duodecimin mainitsemista muista uusista biomarkkereista).

Functions of S100 proteins.

Donato R¹, Cannon BR, Sorci G, Riuzzi F, Hsu K, Weber DJ, Geczy CL. Abstract

The S100 protein family consists of 24 members functionally distributed into three main subgroups: those that only exert intracellular regulatory effects, those with intracellular and extracellular functions and those which mainly exert extracellular regulatory effects. S100 proteins are only expressed in vertebrates and show cell-specific expression patterns. In some instances, a particular S100 protein can be induced in pathological circumstances in a cell type that does not express it in normal physiological conditions. Within cells, S100 proteins are involved in aspects of regulation of proliferation, differentiation, apoptosis, Ca2+ homeostasis, energy metabolism, inflammation and migration/invasion through interactions with a variety of target proteins including enzymes, cytoskeletal subunits, receptors, transcription factors and nucleic acids. Some S100 proteins are secreted or released and regulate cell functions in an autocrine and paracrine manner via activation of surface receptors (e.g. the receptor for advanced glycation end-products and toll-like receptor 4), G-protein-coupled receptors, scavenger receptors, or heparan sulfate proteoglycans and N-glycans. Extracellular S100A4 and S100B also interact with epidermal growth factor and basic fibroblast growth factor, respectively, thereby enhancing the activity of the corresponding receptors. Thus, extracellular S100 proteins exert regulatory activities on monocytes/macrophages/microglia, neutrophils, lymphocytes, mast cells, articular chondrocytes, endothelial and vascular smooth muscle cells, neurons, astrocytes, Schwann cells, epithelial cells, myoblasts and cardiomyocytes, thereby participating in innate and adaptive immune responses, cell migration and chemotaxis, tissue development and repair, and leukocyte and tumor cell invasion.

Free PMC Article

Fig. (6)

Schematic representation of proposed intracellular effects of S100B. S100B interacts with several intracellular proteins as shown thereby regulating protein phosphorylation, enzyme activities, the state of assembly of certain cytoskeleton components, the transcription factor p53, protein degradation, cell proliferation, locomotion and differentiation, dark adaptation of photoreceptors, Ca²⁺ homeostasis and the innate inflammatory response.

S100B

S100B is expressed in astrocytes, certain neuronal populations, Schwann cells, melanocytes, chondrocytes, adipocytes, skeletal myofibers and associated satellite cells, certain dendritic cell and lymphocyte populations and a few other cell types [7]. It acts as a stimulator of cell proliferation and migration and an inhibitor of apoptosis and differentiation [101-111] (Fig. 6), which might have important implications during brain, cartilage and skeletal muscle development and regeneration/repair, activation of astrocytes in the course of brain damage and neurodegenerative processes, and of cardiomyocyte remodeling after infarction, as well as in melanomagenesis and gliomagenesis. In particular, downregulation of S100B expression in precursor cells in a defined temporal window appears to be permissive for cell differentiation [101-106,108-110]. Sex-determining region Y-type high mobility group box 5, 6 and 9 (the so-called SOX trio), NF-κB, EGF and the Th-1-derived cytokine IFN-γ, regulate S100B expression in several cell types [see 7 for review; also see 12]. However, cells that downregulate S100B expression at the onset of their differentiation resume S100B expression at completion of development [7,106], and in mature cells the protein regulate a large variety of key activities including maintenance of shape, transcription, protein degradation, Ca²⁺ homeostasis, energy metabolism and enzyme functions by interacting with a wide array of target proteins. Binding partners of S100B within cells are tubulin and the microtubule-associated τ protein, the actin-binding protein caldesmon, calponin, type III intermediate filament subunits, annexin 6 [7,112-119], membrane-bound guanylate cyclase, the small GTPase Rac1 and Cdc42 effector IQGAP1, Src kinase, the serine/threonine protein kinase Ndr, the tumor suppressor p53, intermediates upstream of IKKβ/NF-κB, the giant phosphoprotein AHNAK/desmoyokin, the E3 ligase hdm2, dopamine D2 receptor and the mitochondrial AAA ATPase, ATAD3A [7,120,121] (Fig. 6). Thus, lack of S100B downregulation may maintain cell proliferation with potential beneficial effects during development and tissue regeneration, and detrimental effects during tumorigenesis. S100B also regulates Ca²⁺ homeostasis [122-125], but opposing results were reported in astrocytes and VSMCs [122,124] (Fig. 6). Moreover, S100B binds to, and inhibits EAG1 potassium channels Ca²⁺-dependently (Fig. 6) raising the possibility that its negative effects on cell differentiation may be via this mechanism as well [125]. Chronically high S100B levels such as those obtained in S100B transgenic mice are proposed to be causally correlated with Parkinson's disease likely via downregulation of dopamine D2 receptor and G protein-coupled receptor kinase2 expression, increased dopamine synthesis and metabolism, and decreased serotonin levels [126] and/or S100B interaction with the third cytoplasmic loop of the dopamine D2 receptor and extracellular signal-regulated kinase (ERK)1/2-mediated inhibition of adenylyl cyclase activity in striatal neurons [127] (Fig. 6). S100B is highly expressed in astrocytes [7] and to a lesser extent in certain neuronal populations [128,129], and its elevation in serum positively correlates with mood disorders [130] and schizophrenia [131]. Serum levels of S100B are of prognostic value in patients with cutaneous melanoma [105] and breast cancer [132]. Whether serum levels of S100B are an outcome predictor in severe traumatic brain injury is a matter of debate [133,134].