Using blood calprotectin as a measure of blood neutrophils

Abstract

Presently, bed-side or at home quantification of neutrophils in blood (b-neutrophils) is not practical, because cytometric methods are too expensive and technically demanding. We have explored whether calprotectin concentration in whole blood (b-calprotectin) might be a valid measure of b-neutrophils because this principle might be used in a simple and robust immunoassay device. We obtained heparin blood samples from 77 patients with possible neutropenia, most of them cancer patients treated with cytostatic drugs, and compared b-calprotectin with their b-neutrophils in a simultaneously taken EDTA-blood sample. The Spearman rank correlation coefficient between b-calprotectin and b-neutrophils was 0.986 (p < .0001). In a regression model of b-neutrophils as a function of age, gender, type of hematology instrument, total leukocyte count minus neutrophils, b-calprotectin, and plasma calprotectin (p-calprotectin), only b-calprotectin was a statistically significant predictor. B-neutrophils below 1 Â 10 9 /L was unlikely if b-calprotectin was above 50 mg/L. In conclusion, b-calprotectin, without adjusting for p-calprotectin, correlates closely with b-neutrophils and could be used to detect b-neutrophils below 1 Â 10 9 /L.

Fetal Immunomodulatory Environment Following Cartilage Injury—The Key to CARTILAGE Regeneration?

“…Cathelicidins are known as antimicrobial effector molecules characteristic for innate immune response and have been described in humans as biomarker for joint infection predominantly expressed by neutrophils [ 36 ]. Protein S100A8, contained in calprotectin, is reported to be a reliable blood marker for neutrophils [ 37 ]. Myeloid antimicrobial peptide (Map-34) is another effector molecule with anti-microbial properties, which was significantly upregulated in adult samples.…”

S100A8 and S100A9 in Hematologic Malignancies: From Development to Therapy

“…S100A8/A9 has been identified to be a biomarker in the inflammatory stages of numerous diseases such as ulcerative colitis and acute respiratory infections [34][35][36][37][38][39]. In addition, plasma levels of S100A8/A9 can be a surrogate of blood neutrophil count (below 1 × 10 9 /L) as a cost-effective, easier, and at-home method for monitoring and evaluating patients compared with flow cytometry [40]. Moreover, a study using quantitative protein expression profiling concluded that upregulated S100A8 in serum can be a diagnostic biomarker in two groups of childhood leukemia (B and T cell acute lymphoblastic leukemia; B and T-ALL) [41].…”

“…In addition, they observed a reduction in FIP1L1-PDGFRα-mediated signaling by decreasing FIP1L1-PDGFRα gene expression in the presence of recombinant S100A8 and S100A9 [63] (Figure 4A). Another group showed that the in vitro administration of human recombinant S100A8/A9 (10,20,40,80, and 100 mg/mL) on Nalm6 leukemia cell line induces an apoptotic effect in a time-and dose-dependent manner (after 24, 48, and 72 h) [64] (Figure 4B). A study by Kim et al also revealed the pro-apoptotic effect of S100A8 and/or S100A9 (10 ug/mL for 48 and 72 h) on human monocytic leukemia cells (THP-1) which express high levels of TLR-4 [65] (Figure 4C).…”