Plasma Concentrations Of Calprotectin Research Articles

Assessment of the predictive value of plasma calprotectin in the evolution of SARS-Cov-2 primo-infection

BackgroundThe COVID-19 epidemic still calls for anticipation aimed at preventing the overloading of critical care services. With this in mind, the predictive value of easily accessible biomarkers is to be assessed. ObjectiveSecretion of calprotectin is stimulated during an inflammatory process, especially in the cytokine storm. We tried to determine whether early plasma concentration of calprotectin in patients with primary SARS-CoV-2 infection could predict an adverse outcome in cases of COVID-19. MethodsWe included 308 patients with a primary diagnosis of SARS-CoV-2 confirmed by PCR. Heparinized tube samples, collected within the first 24 h of hospitalization, were used for biomarker assays, in which plasma calprotectin was included. Data from the patients' medical records and severity groups established subsequent to diagnosis at the end of hospitalization were collected. ResultsEarly plasma calprotectin concentration is significantly associated with progression to a severe form of COVID-19 in patients with primary infection (Relative Risk: 2.2 [1.6–2.7]). In multivariate analysis, however, it does not appear to provide additional information compared to other parameters (age, GFR, CRP…). ConclusionOur study shows that while an early single blood test for calprotectin could help to predict the progression of a primary SARS-CoV-2 infection, it is not superior to the other parameters currently used in emergency medicine. However, it paves the way for future considerations, such as the interest of this biomarker for high-risk infected patients (immunocompromised individuals…). Finally, the usefulness of early serial measurements of plasma calprotectin to assess progression towards severity of COVID-19 requires further assessment.

Plasma calprotectin is extremely high in patients with lysinuric protein intolerance.

Lysinuric protein intolerance (LPI) is a rare autosomal recessive disorder affecting the transport of cationic amino acids. Elevated plasma zinc concentrations have been described in patients with LPI. Calprotectin is a calcium- and zinc-binding protein, produced by polymorphonuclear leukocytes and monocytes. Both zinc and calprotectin have an important role in immune system. In this study, we describe plasma zinc and plasma calprotectin concentrations in Finnish LPI patients. Plasma calprotectin concentration was measured from 10 LPI patients using an enzyme-linked immunosorbent assay (ELISA) and it was remarkably high in all LPI patients (median: 622 338 μg/L) compared to that in healthy controls (608 μg/L). Plasma zinc concentration was measured by photometry and it was normal or only mildly elevated (median: 14.9 μmol/L). All the patients had decreased glomerular infiltration rate (median: 50 mL/min/1.73 m2). In conclusion, we observed extremely high plasma calprotectin concentration in patients with LPI. Mechanism of this phenomenon is unknown.

Increased levels of NETosis biomarkers in high-grade serous ovarian cancer patients' biofluids: Potential role in disease diagnosis and management.

High-grade serous ovarian cancer (HGSOC) is the second most frequent gynecological malignancy but the most lethal, partially due to the spread of the disease through the peritoneal cavity. Recent evidence has shown that, apart from their role in immune defense through phagocytosis and degranulation, neutrophils are able to participate in cancer progression through the release of neutrophil extracellular traps (NETs) in a process called NETosis. NETs are composed of DNA, histones, calprotectin, myeloperoxidase (MPO) and elastase and the NETosis process has been proposed as a pre-requisite for the establishment of omental metastases in early stages of HGSOC. Nevertheless, its role in advanced stages remains to be elucidated. Therefore, our principal aim is to characterize a NETosis biomarker profile in biofluids from patients with advanced HGSOC and control women. Specifically, five biomarkers of NETosis (cell-free DNA (cfDNA), nucleosomes, citrullinated histone 3 (citH3), calprotectin and MPO) were quantified in plasma and peritoneal fluid (PF) samples from patients (n=45) and control women (n=40). Our results showed that HGSOC patients presented a higher concentration of cfDNA, citH3 and calprotectin in plasma and of all five NETosis biomarkers in PF than control women. Moreover, these biomarkers showed a strong ability to differentiate the two clinical groups. Interestingly, neoadjuvant treatment (NT) seemed to reduce NETosis biomarkers mainly systemically (plasma) compared to the tumor environment (PF). In conclusion, NETosis biomarkers are present in the tumor environment of patients with advanced HGSOC, which might contribute to the progression of the disease. Besides, plasma cfDNA and calprotectin could represent minimally invasive surrogate biomarkers for HGSOC. Finally, NT modifies NETosis biomarkers levels mainly at the systemic level.

Сalprotectin in the blood plasma as a new biomarker for assessing the activity of rheumatoid arthritis

Aim. To study the potential use and information value of calprotectin in the blood plasma as a new biomarker for determining the activity of rheumatoid arthritis (RA).Materials and methods. The study included 113 people. The treatment group consisted of 79 patients diagnosed with RA; the average age was 58 (± 11.66) years, the median duration of the disease was 10 [6; 15] years. The control group encompassed 34 healthy volunteers; the average age was 40 (± 11.14) years. RA activity was determined according to the Disease Activity Score (DAS) 28 and the Clinical Disease Activity Index (CDAI). The concentration of calprotectin in the blood plasma was determined by the solid-phase enzyme-linked immunosorbent assay. The obtained results were compared with laboratory and clinical parameters, as well as with composite indices (DAS28, CDAI) of RA activity. For mathematical data processing, Spearman’s rank correlation coefficient, linear discriminant analysis, and ROC analysis were used.Results. In the group of patients with RA, the level of calprotectin in the blood was higher than in the control group. A statistically significant relationship was revealed between the level of calprotectin in the blood and all standard parameters of RA activity. The ROC analysis showed that the sensitivity, specificity, and diagnostic accuracy in assessing articular syndrome, as well as moderate and high RA activity according to the composite indices DAS28 and CDAI were higher for calprotectin than for erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). The linear discriminant analysis showed that a combination of ESR and calprotectin levels was the most informative; following it, the probability of correct classification of RA activity, according to the DAS28 index, was 71%. For the CDAI index, only one marker, calprotectin, resulted in a statistically significant classification with a probability of 70.5 %.Conclusion. Сalprotectin in the blood plasma is a promising laboratory biomarker for assessing synovitis activity in RA demonstrating higher accuracy, sensitivity, and specificity than traditional acute-phase reactants.

Plasma Calprotectin Is Predictive for Short-Term Functional Outcomes of Acute Ischemic Stroke.

BackgroundBlood-based prognostic biomarkers of acute ischemic stroke (AIS) are limiting. Calprotectin is suggested to be involved in directing post-stroke inflammatory conditions. However, the pathological alteration of circulating calprotectin in AIS is yet to be thoroughly elucidated. Therefore, this study aimed to investigate the levels and clinical relevance of calprotectin in AIS.MethodsThis study recruited 271 patients with AIS within 24 h since symptom onset and 145 non-stroke healthy controls (HC) from February 1, 2018, to Dec 31, 2020. Patients were followed up for 2 weeks for observation of functional outcomes, as determined by the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). Plasma calprotectin concentrations were determined by ELISA.ResultsPlasma calprotectin concentrations were significantly higher in patients with AIS compared with controls [patients vs. control: median (IQR) 54.2 (39.01–99.04) vs. 50.04 (35.42–61.22), p < 0.001]. Besides, patients with poor prognosis, as defined by mRS ≥ 3, had significantly higher calprotectin levels than patients with good prognosis [poor prognosis patients vs. good prognosis patients: median (IQR) 61.99 (47.52–108) vs. 43.36 (33.39–60.2), p < 0.001]. Plasma calprotectin levels were positively associated with the disease severity of AIS, as reflected by infarction volume and NIHSS score at baseline. Furthermore, baseline calprotectin was found to be independently associated with poor prognosis [odds ratio (OR): 1.02, 95% CI: 1.01–1.03] and disease progression (OR: 1.03, 95% CI: 1.02–1.04) of AIS during a 2-week follow-up, with adjustment of possible confounding factors.ConclusionPlasma calprotectin is associated with short-term functional outcomes of AIS.

Analytical and clinical evaluation of DiaSorin Liaison® Calprotectin fecal assay adapted for serum samples.

BackgroundCalprotectin is a calcium‐binding protein that can be measured in serum, plasma, and feces. Increased serum and plasma calprotectin concentrations have been found in chronic inflammatory rheumatic disorders. An analytical and clinical evaluation of the DiaSorin Liaison® fecal Calprotectin assay using LIAISON® XL was performed.MethodsThe protocol included an analytical and clinical evaluation in which imprecision, the linearity of dilution, differences between serum and plasma samples and method comparison with CalproLab™ ELISA kit were assessed. Serum calprotectin concentrations in active (n = 26) and remission (n = 23) rheumatoid arthritis (RA) patients were compared.ResultsThe intra‐day and inter‐day analytical imprecision CVs ranged from 2.9% to 4.0% and 2.7% to 10.4%, respectively. Correlation between measured and expected values was high (R > 0.99), indicating good linearity. The Wilcoxon signed‐rank test showed that serum and plasma matched samples presented statistically significant differences (p < 0.001) being the highest concentrations of calprotectin observed in serum samples. Deming regression equation was as follows: Diasorin calprotectin (μg/ml) = −0.32 (95% CI: −0.65 ‐ −0.05) +1.58 (95% CI: 1.42–1.79).* Calprolab calprotectin (μg/ml). Significantly higher serum calprotectin levels were found in RA patients with active disease when compared to patients with low disease activity or in clinical remission (mean ± SD) [(3.35 μg/ml ± 1.55) vs. (1.63 μg/ml ± 0.52), p < 0.001] and these levels correlated well with all disease activity indices.ConclusionsThe DiaSorin Liaison® fecal Calprotectin assay adapted for serum samples showed adequate technical performances and the clinical performances were similar to other assays.

The Role of Serum Calprotectin as a New Marker in Abdominal Aortic Aneurysms - A Preliminary Report.

Abdominal Aortic Aneurysm (AAA) remains a surgical challenge. There are many recognizable markers associated with the formation of AAA. Previous experiments carried out on animal models have shown a correlation between serum calprotectin and the occurrence of AAA. This study aimed to evaluate the level of calprotectin as a potential diagnostic biomarker in patients with diagnosed AAA. The study group consisted of 75 patients aged 35-75 years assigned to two groups: a control group (n=43) of healthy subjects without AAA and a study group (n=32) of patients with a diagnosed AAA. The first calprotectin test was performed upon patient admission to the hospital, and the second control test was performed after three months. The concentration of calprotectin in plasma was determined using the Immunoenzymatic Method (ELISA) with the commercially available Assaypro Kit (AssayMax™ Human Calprotectin ELISA Kit), as well as the sandwich method with polyclonal antibodies to human calprotectin and peroxidase enzyme. Serum calprotectin levels in AAA patients were three times higher than in healthy subjects (p<0.05). A statistically significant twofold decrease in calprotectin concentration was observed after AAA surgery compared to the control group (p<0.05). Calprotectin levels can be an important marker in the detection of AAA. In conclusion, AAA patients showed a threefold increase in serum calprotectin level and a twofold decrease in this marker after AAA surgery.

Calprotectin and Receptor for Advanced Glycation End Products as a Potential Biomarker in Abdominal Aortic Aneurysm.

Experiments conducted in recent years on animals and research works worldwide show a linkage between calprotectin and occurrence and development of the abdominal aortic aneurysm (AAA). Additionally, a correlation between the level of the receptor for advanced glycation end products (RAGE) and the diameter of the abdominal aorta was found. The purpose of this study was to investigate whether calprotectin and the RAGE plasma level may be a biomarker of human AAA occurrence. We determined two groups of research participants: a group of 32 patients aged 53–88 undergoing primary endovascular aneurysm repair and a control group of 43 volunteers aged 59–82 without the AAA. All the patients from the study group had their blood samples drawn in order to determine the level of calprotectin and RAGE in plasma. The second follow-up examination was carried out after three months. The concentration of calprotectin and RAGE in plasma was determined with the use of the immunoenzymatic method (ELISA). The study showed that patients with the AAA had significantly higher mean calprotectin and RAGE plasma levels (p = 0.0001 and p = 0.0002, respectively) as compared to the control group. After the AAA repair operations, the level of concentration of the calprotectin decreased significantly (p = 0.0002). So far, no studies on the connection between the increase of the calprotectin and RAGE in the patient’s plasma with the AAA have been published. Calprotectin may be a promising biomarker related to the occurrence of AAA. Larger studies are needed to fully elucidate and confirm the role of calprotectin in the development and progression of the aneurysm.

Inflammatory Response 24 h Post-Exercise in Youth with Juvenile Idiopathic Arthritis.

The aim of this study was to measure the impact, at 24 h post-exercise, of a single exercise bout on plasma inflammatory markers such as calprotectin, IL-6, sIL-6 R, sgp130 and the hypothalamic-pituitary-adrenal (HPA) axis in children with juvenile idiopathic arthritis (JIA).Twelve children with JIA attended the laboratory on three consecutive days (control day, exercise day and 24 h post-exercise), including a 20-min exercise bout on a cycle-ergometer at 70% of max. HR at 8:30 a.m. on day 2. Plasma concentrations of calprotectin, IL-6, sIL-6 R, sgp130, cortisol, ACTH and DHEA were measured on venous blood samples taken every day.at rest and at 8:30, 8:50, 9:30, 10:30 a.m. and 12:00, 3:00, 5:30 p.m.A single exercise bout increased plasma calprotectin 1.7-fold (p<0.001) but did not increase IL-6 and soluble IL-6 receptors in short-term post-exercise recovery. However, at 24 h post-exercise, calprotectin, IL-6 and its receptors had decreased compared to control-day levels. There was a transient 2-fold increase in post-exercise self-evaluated pain (p=0.03) that disappeared in the evening without repercussions the following day.Physical activity in children with JIA results in a slight transient systemic inflammation but seems to be followed by counter-regulation at 24 h post-exercise with a decrease in proinflammatory markers.

The use of selected neutrophil protein plasma concentrations in the diagnosis of Crohn's disease and ulcerative colitis - a preliminary report.

Difficulties in diagnosis of inflammatory bowel disease (IBD) motivate the search for new diagnostic tools, including laboratory tests. The aim of this study was to evaluate concentrations of the neutrophil (NEU) proteins leukocyte elastase (HLE-α1AT), lactoferrin and calprotectin as potential biomarkers used in the diagnosis and assessment of clinical activity of Crohn's disease (CD) and ulcerative colitis (UC). The study included 27 patients with CD, 33 patients with UC and 20 healthy controls. Plasma concentrations of calprotectin, lactoferrin and HLE-α1AT were measured using ELISA. In patients with CD higher concentrations of HLE-α1AT (64.3±43.1 vs. 30.1±7.7 ng/l, P<0.001), calprotectin (151.6±97.8 vs. 69.9±22.1 ng/l, P<0.001) and lactoferrin (243.2±102.0 vs. 129.7±32.7 ng/l, P<0.001) than in the control group were found. In patients with UC higher plasma concentrations of HLE-α1AT (62.0±30.9 vs. 30.1±7.7 ng/l, P<0.001), calprotectin (149.6±72.3 vs. 69.9±22.1 ng/l, P<0.001) and lactoferrin (242.6±107.5 vs 129.7±32.7 ng/l, P<0.001) than in the control group were found. HLE-α1AT/NEU and lactoferrin/NEU ratios in patients with UC were significantly higher compared with patients with CD. Calprotectin (P=0.010) and lactoferrin (P=0.023) levels were higher in patients with the active compared with inactive phase of CD. The diagnostic characteristics of plasma granulocyte protein concentrations indicate the usefulness of these tests in the diagnosis of IBD. Higher HLE-α1AT and lactoferrin/NEU ratios in patients with UC than with CD may suggest the usefulness of these ratios in differential diagnostics. Plasma calprotectin and lactoferrin levels may be useful in CD activity assessment.

Exercise-Induced Inflammation during Different Phases of the Menstrual Cycle

Objective: To examine the effects of menstrual cycle on exercise-induced inflammation, we investigated exercise-induced changes in circulating cytokines and leukocyte responses during different phases of the menstrual cycle. Methods: Ten healthy sedentary females (20.5 ± 0.7 years) performed 60 min of cycling at 75% of their individual anaerobic threshold (AT) during the three different phases of the menstrual cycle (menstrual, follicular and luteal phases). Blood and saliva were sampled baseline, post- and 30 min post-exercise. The salivary concentrations of female sex hormones, progesterone and 17β-estradiol, and plasma concentrations of pro-inflammatory cytokines, interleukin (IL)-6 and IL-8, and markers of leukocyte activation, calprotectin and myeloperoxidase, were measured in all the blood and saliva sampling intervals. Results: The plasma concentration of IL-6 increased significantly post-exercise (p<0.001) and the plasma concentration of calprotectin increased significantly 30 min post-exercise (p<0.05) in all the three menstrual cycle phases. A positive correlation was found between exercise-induced changes in plasma IL-6 and calprotectin concentrations in the menstrual phase, suggesting the possibility of enhanced leukocyte reactivity to IL-6 during this phase. Conclusion: These findings suggest that 60 min of strenuous exercise at an intensity of higher than 75% AT may induce inflammation in sedentary females, especially during the menstrual phase of the menstrual cycle.

A new turbidimetric immunoassay for serum calprotectin for fully automatized clinical analysers.

Serum and plasma calprotectin concentration is shown to be elevated when neutrophils are activated, and may therefore be used as a marker for inflammatory diseases. A serum calprotectin immunoassay was developed based on calprotectin values observed in samples from the intensive care unit. The polyclonal avian antibodies were raised and affinity purified with calprotectin antigens. The performance was tested and it was observed that the assay was linear in the range 0.3–24.7 mg/L, the limit of quantitation was observed to be lower than 0.3 mg/L, no antigen excess was observed up to 54 mg/L, all CVs were lower than 1.8 % in the precision study, the calibration curve stability was longer than 6 weeks, and there was no significant interference detected for haemoglobin, intralipid or bilirubin. The serum calprotectin immunoassay presented in this paper performs well within the criteria carefully set from the limited clinical experience obtained in both serum and plasma. In addition it is commutable with Bühlmann MRP8/14 ELISA.

The correlation between plasma calprotectin and neutrophil count in patients with aggressive periodontitis

To measure the levels of plasma calprotectin in aggressive periodontitis (AgP) patients and to analyze the relationship between the plasma calprotectin and neutrophil count. Venous blood samples were collected from 61 AgP patients and 48 periodontally healthy controls. Clinical examination consisted of bleeding index (BI), probing depth (PD), attachment loss measurements (AL) and percentage of severe sites. Plasma level of calprotectin was determined by enzyme-linked immunosorbent assay. The plasma concentrations of calprotectin in AgP patients [(2.1±1.1) mg/L] were significantly higher than those in healthy controls[(1.5±0.6) mg/L] (P < 0.01). The plasma concentration of calprotectin in AgP patients was positively correlated with BI (r = 0. 271, P = 0.035), PD (r = 0.437, P = 0.000), AL (r = 0.450, P = 0.000) and percentage of severe sites (r = 0.423, P = 0.001). While the neutrophil count was also positively correlated with the plasma concentrations of calprotectin in AgP patients (r = 0.380, P = 0.004). AgP may have impact on the elevation of plasma level of calprotectin.

Analysis of plasma calprotectin and polymorphisms of S100A8 in patients with aggressive periodontitis

Calprotectin is an important proinflammatory mediator in various inflammatory diseases and is composed of two subunits (S100A8 and S100A9). However, the level of calprotectin in plasma of patients with aggressive periodontitis and its relationship with gene polymorphisms of S100A8 are unclear. The plasma concentrations of calprotectin were measured, using an enzyme immunoassay, in 139 patients with aggressive periodontitis and in 88 periodontally healthy control subjects. These patients were genotyped for the rs3795391 and rs3806232 polymorphisms of S100A8. The plasma concentration of calprotectin in patients with aggressive periodontitis was significantly higher than in controls (2.17 mg/L vs. 1.72 mg/L, respectively, p = 0.001). The percentage of the AA genotype of S100A8 rs3795391 was significantly higher in patients than in controls (82% vs. 69.3%, respectively, p = 0.027), while the frequency of the allele G was decreased among patients compared with controls (9.6% vs. 16.1%, respectively, p = 0.036), which was especially apparent in men (rs3795391 genotype, p = 0.005; rs3795391 allele, p = 0.015). The mean probing depth in patients carrying the AA genotype was significantly higher than that of patients carrying the GA + GG genotype of two polymorphisms of S100A8 (rs3795391, p = 0.035; rs3806232, p = 0.040), whereas the levels of calprotectin between different genotypes were not significantly different (rs3795391, p = 0.11; rs3806232, p = 0.15). These findings indicate that aggressive periodontitis is associated with elevated levels of plasma calprotectin and that gene polymorphisms of S100A8 may influence the susceptibility and severity of aggressive periodontitis.

Plasma calprotectin as inflammation marker in pregnancies complicated by diabetes mellitus and superimposed preeclampsia

Objective We hypothesized that pregnancies complicated by diabetes mellitus with or without preeclampsia show an elevated systemic inflammatory response evaluated by the inflammation markers calprotectin and high-sensitivity C-reactive protein (hsCRP). Study design Third trimester EDTA plasma and serum from 138 women with diabetes mellitus (type 1, n = 53; type 2, n = 11; gestational diabetes mellitus (GDM), n = 63; diabetes mellitus with preeclampsia, n = 11) were analyzed for calprotectin and hsCRP and compared to previously published results from 37 healthy and 27 preeclamptic pregnancies. Results Median plasma calprotectin concentration was intermediate in women with GDM as compared to healthy and preeclamptic pregnancies (729 vs 552 and 1081 μg/L, P = .006 and P = .001, respectively). In diabetic pregnancies with preeclampsia, median plasma calprotectin concentration was elevated as compared to controls, but not different from women with preeclampsia alone (969 vs 552 and 1081 μg/L, P = .01 and P = .1, respectively). hsCRP was only elevated in type 2 diabetic pregnancies as compared to healthy pregnancies (6.6 vs 3.8 mg/L, P =.02). Conclusion Elevated plasma calprotectin concentrations in GDM may reflect an accentuated inflammatory process, possibly contributing to the augmented preeclampsia risk. Increased plasma calprotectin in diabetic pregnancies with preeclampsia may originate from the excess systemic inflammatory response associated with preeclampsia.

Plasma calprotectin concentrations in women with endometrial carcinoma

Objectives There is a lack of circulating markers to predict disease outcome, therapy effect and monitoring for disease recurrence in endometrial cancer. The aim of this study was to explore whether plasma concentration of the inflammatory marker calprotectin is elevated in endometrial cancer and related to clinical parameters. Methods Calprotectin in EDTA-plasma samples from women with primary endometrial carcinoma ( n = 194), from healthy premenopausal ( n = 20) and postmenopausal ( n = 20) women was analyzed with ELISA. Results Median plasma calprotectin concentration was elevated in the patient group of endometrial cancer (3415 μg/L) as compared to the healthy premenopausal (832 μg/L) and postmenopausal groups (868 μg/L), both p < 0.001. Also, median calprotectin concentration was elevated in the endometrial cancer group as compared to women with invasive ovarian cancer, borderline ovarian tumor and benign ovarian tumors. Calprotectin plasma concentration correlated significantly with poor survival and high FIGO stage in endometrial carcinoma. Conclusion Calprotectin is elevated in plasma of women with endometrial carcinoma. Further studies are warranted to assess its possible value as a clinical tool for evaluating disease progression and relapse, as well as in monitoring treatment response.

Monomeric Calgranulins Measured by SELDI-TOF Mass Spectrometry and Calprotectin Measured by ELISA as Biomarkers in Arthritis

SELDI-TOF mass spectrometry (MS) is a high-throughput proteomic approach with potential for identifying novel forms of serum biomarkers of arthritis. We used SELDI-TOF MS to analyze serum samples from patients with various forms of inflammatory arthritis. Several protein profiles were collected on different Bio-Rad Laboratories ProteinChip arrays (CM10 and IMAC-Cu(2+)) and were evaluated statistically to select potential biomarkers. SELDI-TOF MS analyses identified several calgranulin proteins [S100A8 (calgranulin A), S100A9 (calgranulin B), S100A9*, and S100A12 (calgranulin C)], serum amyloid A (SAA), SAA des-Arg (SAA-R), and SAA des-Arg/des-Ser (SAA-RS) as biomarkers and confirmed the results with other techniques, such as western blotting, immunoprecipitation, and nano-LC-MS/MS. The S100 proteins were all able to significantly differentiate samples from patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) from those of patients with inflammatory bowel diseases used as an inflammatory control (IC) group, whereas the SAA, SAA-R, and SAA-RS proteins were not, with the exception of AS. The 4 S100 proteins were coproduced in all of the pathologies and were significantly correlated with the plasma calprotectin concentration; however, these S100 proteins were correlated with the SAA peak intensities only in the RA and IC patient groups. In RA, these S100 proteins (except for S100A12) were significantly correlated with the serum concentrations of C-reactive protein, matrix metalloproteinase 3, and anti-cyclic citrullinated peptide and with the Disease Activity Score (DAS(28)). The SELDI-TOF MS technology is a powerful approach for analyzing the status of monomeric, truncated, or posttranslationally modified forms of arthritis biomarkers, such as the S100A8, S100A9, S100A12, and SAA proteins. The fact that the SELDI-TOF MS data were correlated with results obtained with the classic calprotectin ELISA test supports the reliability of this new proteomic technique.

Circulating calprotectin in ovarian carcinomas and borderline tumors of the ovary

Recent studies indicate that circulating calprotectin may serve as a biomarker in some cancers. We investigated whether this is the case for ovarian neoplasms. Calprotectin was analyzed with an enzyme-linked immunosorbent assay in EDTA-plasma collected prior to surgery from women with ovarian carcinomas (n = 89), borderline ovarian tumors (BOT, n = 39), and benign ovarian tumors (n = 71). Serum CA 125 was analyzed in the same study population. Median plasma calprotectin concentration was elevated in ovarian carcinoma, compared with controls, as well as compared with BOT (both P < .001). A positive correlation was found between CA 125 and calprotectin concentrations in ovarian carcinoma. Receiver operating characteristic curves demonstrated a larger area under the curve for CA 125 (0.85) as compared with calprotectin (0.70). Plasma calprotectin is elevated in invasive ovarian cancer, but when used as a tumor marker, it is inferior to CA 125.

Is plasma concentration of calprotectin a measure of joint inflammation and damage in RA?

Is plasma concentration of calprotectin a measure of joint inflammation and damage in RA?

Severe Anemia and Neutropenia Associated With Hyperzincemia and Hypercalprotectinemia

Calprotectin, also known as the S100A8/A9 or MRP8/14 complex, is a major calcium-binding protein in the cytosol of neutrophils, monocytes, and keratinocytes. It differs from other S100 proteins in its zinc-binding capacity. The authors describe a 4-year-old girl with severe anemia, neutropenia, inflammation, and severe growth failure. Bone marrow examination showed moderate dyserythropoiesis. No hemolysis, iron deficiency, hemoglobinopathies, immunologic diseases, or autoantibodies were detected. Serum levels of copper and ceruloplasmin were within the normal range, although the serum zinc concentration was markedly increased (310 microg/dL). Urinary zinc excretion and erythrocyte zinc concentrations were within the normal range. Family studies showed normal zinc and copper plasma levels. The patient's plasma calprotectin concentration showed a 6,000-fold increase (2,900 mg/L) compared with normal values. The calprotectin concentration is known to be elevated in many inflammatory conditions but is generally below 10 mg/L and thus far below the levels reported in this patient. The authors describe this case as an inborn error of zinc metabolism caused by dysregulation of calprotectin metabolism, which mainly presented with the features of microcytic anemia and inflammation.