quantikine human calprotectin heterodimer immunoassay  (R&D Systems)

Journal: Frontiers in Pediatrics

Article Title: Noninvasive salivary biomarkers (PTX3, calprotectin, and IL-8) for early-onset neonatal pneumonia: case-control differences and exploratory discrimination

doi: 10.3389/fped.2026.1747967

Figure Lengend Snippet: Salivary PTX3, calprotectin, and IL-8 are elevated in early-onset neonatal pneumonia (EONP) and show strong case—control discrimination. (A – C) Distributions of salivary PTX3, calprotectin, and IL-8 in EONP vs. healthy controls (medians with IQRs; Mann–Whitney tests, all P < 0.001). (D – F) ROC curves for each single biomarker with optimal cutoffs (PTX3 ≥ 1.38 ng/mL; calprotectin ≥5.49 ng/mL; IL-8 ≥ 8.69 pg/mL). The solid line denotes the ROC curve and the dashed lines indicate the 95% confidence interval (lower and upper limits). (G) ROC curves for the three-marker combined model (logistic regression using PTX3, calprotectin, and IL-8). The combined model achieved an apparent AUC of 0.978, and internally validated performance is overlaid (LOOCV and 5-fold cross-validation), demonstrating minimal performance degradation.

Article Snippet: Salivary PTX3, calprotectin, and IL-8 concentrations were measured using commercial ELISA kits according to the manufacturers' instructions: PTX3 with the QuantikineTM Human Pentraxin 3 Immunoassay (R&D Systems, Cat. DPTX30B); calprotectin with the Quantikine® Human Calprotectin Heterodimer Immunoassay (R&D Systems, Cat. DS8900); and IL-8 with the LEGEND MAXTM High Sensitivity Human IL-8 ELISA Kit (BioLegend, Cat. 431517).

Techniques: Control, MANN-WHITNEY, Biomarker Discovery, Marker

Journal: Frontiers in Pediatrics

Article Title: Noninvasive salivary biomarkers (PTX3, calprotectin, and IL-8) for early-onset neonatal pneumonia: case-control differences and exploratory discrimination

doi: 10.3389/fped.2026.1747967

Figure Lengend Snippet: Salivary biomarkers are inter-correlated and track systemic inflammation in EONP. (A) Pairwise correlations among salivary PTX3, calprotectin, and IL-8 in EONP (Spearman r , all P < 0.001). (B) Corresponding correlations in healthy controls (all P > 0.05). (C) Heatmap of Spearman correlations between salivary biomarkers and systemic indices (hs-CRP, serum PCT, serum IL-6, WBC, ANC, I/T ratio, platelets) in EONP, showing moderate-to-strong positive associations with inflammatory markers and inverse associations with platelets (panel labels show exact r ).

Article Snippet: Salivary PTX3, calprotectin, and IL-8 concentrations were measured using commercial ELISA kits according to the manufacturers' instructions: PTX3 with the QuantikineTM Human Pentraxin 3 Immunoassay (R&D Systems, Cat. DPTX30B); calprotectin with the Quantikine® Human Calprotectin Heterodimer Immunoassay (R&D Systems, Cat. DS8900); and IL-8 with the LEGEND MAXTM High Sensitivity Human IL-8 ELISA Kit (BioLegend, Cat. 431517).

Techniques:

Journal: Frontiers in Pediatrics

Article Title: Noninvasive salivary biomarkers (PTX3, calprotectin, and IL-8) for early-onset neonatal pneumonia: case-control differences and exploratory discrimination

doi: 10.3389/fped.2026.1747967

Figure Lengend Snippet: Salivary biomarkers modestly enrich for blood-culture-positive bacteremia within EONP. (A – C) Salivary PTX3, calprotectin, and IL-8 in culture-positive vs. culture-negative EONP cases (medians with IQRs; Mann–Whitney P < 0.001, =0.003, =0.002, respectively). (D – F) ROC curves for bacteremia detection using single salivary markers with optimal cutoffs (PTX3 ≥ 2.51 ng/mL; calprotectin ≥14.57 ng/mL; IL-8 ≥ 18.97 pg/mL), yielding AUCs 0.725, 0.682, and 0.689, respectively. The solid line denotes the ROC curve and the dashed lines indicate the 95% confidence interval (lower and upper limits). (G) ROC curves for the three-marker combined model (logistic regression using PTX3, calprotectin, and IL-8). The combined model achieved an apparent AUC of 0.702, with internally validated AUCs of 0.706 (5-fold cross-validation) and 0.702 (LOOCV), indicating stable but moderate enrichment performance.

Article Snippet: Salivary PTX3, calprotectin, and IL-8 concentrations were measured using commercial ELISA kits according to the manufacturers' instructions: PTX3 with the QuantikineTM Human Pentraxin 3 Immunoassay (R&D Systems, Cat. DPTX30B); calprotectin with the Quantikine® Human Calprotectin Heterodimer Immunoassay (R&D Systems, Cat. DS8900); and IL-8 with the LEGEND MAXTM High Sensitivity Human IL-8 ELISA Kit (BioLegend, Cat. 431517).

Techniques: MANN-WHITNEY, Marker, Biomarker Discovery

Journal: Medicine

Article Title: Cellular and soluble plasma immune markers at presentation in multisystem inflammatory syndrome in children and Kawasaki disease in South Africa: An observational study

doi: 10.1097/MD.0000000000041516

Figure Lengend Snippet: Inflammatory markers assessed in blood plasma of healthy controls, MIS-C and KD patients.

Article Snippet: Human S100A8/S100A9 (Calprotectin) Heterodimer Immunoassay and human haptoglobin (HP) Immunoassay commercial enzyme-linked immunosorbent assay kits (R&D Systems, Minneapolis, MN) were used to assess the levels of calprotectin and HP in cryopreserved plasma samples.

Techniques: Clinical Proteomics

Journal: Experimental & molecular medicine

Article Title: TLR7-dependent eosinophil degranulation links psoriatic skin inflammation to small intestinal inflammatory changes in mice.

doi: 10.1038/s12276-024-01225-y

Figure Lengend Snippet: Fig. 1 Psoriatic skin inflammation induces changes in the intestinal microenvironment. a, b Serum concentrations of soluble CD14, calprotectin, and zonulin in healthy individuals and patients with psoriasis. c Schematic of imiquimod (IMQ)-induced psoriatic inflammation. d Serum fluorescein isothiocyanate (FITC)-dextran fluorescence and soluble CD14 and calprotectin concentrations in mice. e Images of hematoxylin and eosin-stained tissues from the small intestine (SI) and large intestine (LI). Scale bars, 124.5 μm. f Ratio of villus length to crypt length. Three to five villi and crypts were analyzed per section. g Calprotectin concentrations in stool. h Sequencing of the stool microbiota of the SI and LI of mice treated with IMQ (n = 3) or vehicle cream (n = 4). Image of the cytokine array membrane (i) and the quantified density (j). The data are presented as the means ± SDs. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001 according to unpaired t tests (b, d, f, h, and CCL2 and CXCL9 in j), Mann–Whitney tests (calprotectin in b and j), or one-way ANOVA with Bonferroni’s multiple comparisons (g).

Article Snippet: A Quantikine Mouse CD14 ELISA Kit (R&D Systems, Minneapolis, MN, USA; cat# MC140) and a DuoSet Mouse Calprotectin ELISA Kit (R&D Systems; cat# DY8596-05) were used according to the manufacturer’s instructions.

Techniques: Staining, Sequencing, Cream, Membrane, MANN-WHITNEY

Journal: Experimental & molecular medicine

Article Title: TLR7-dependent eosinophil degranulation links psoriatic skin inflammation to small intestinal inflammatory changes in mice.

doi: 10.1038/s12276-024-01225-y

Figure Lengend Snippet: Fig. 5 Psoriatic skin inflammation and the increase in intestinal permeability are attenuated in eosinophil-deficient mice. a Schematic of the adoptive transfer (Tf) of bone marrow-derived eosinophils (BMEOs). WT, wild-type; ΔEO, ΔdblGATA. (b) Hematoxylin and eosin-stained skin. Scale bars, 124.5 μm. c Epidermal thickness. Three distinct regions of each section were analyzed. d Transepidermal water loss (TEWL) (n = 9 or 10/group). *P < 0.05, ***P < 0.001, and ****P < 0.0001, WT IMQ vs. ΔEO IMQ; #P < 0.05, ##P < 0.01, ΔEO IMQ + BMEO Tf vs. ΔEO IMQ. e Quantitative PCR analysis of the skin. f Serum concentrations of eosinophil peroxidase (EPX) and calprotectin. g Stool concentrations of EPX and calprotectin. h Quantitative PCR analysis of the small intestine (SI). Occludin and mucin 2 (green) immunofluorescence staining (i) and quantification (j) in the SI. Nuclei were stained with 4’,6-diamidino-2-phenylindole (DAPI; blue). The fluorescence intensity of each section was analyzed. Scale bars, 62.3 μm. The data are presented as the means ± SDs. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001; one-way ANOVA with Tukey’s multiple comparisons (c, e, f, and h); Kruskal–Wallis test with Dunn’s multiple comparisons (Il23 in e, g, and Tnf and Tjp1 in h); two-way ANOVA with Bonferroni’s multiple comparisons (d); or unpaired t test (j).

Article Snippet: A Quantikine Mouse CD14 ELISA Kit (R&D Systems, Minneapolis, MN, USA; cat# MC140) and a DuoSet Mouse Calprotectin ELISA Kit (R&D Systems; cat# DY8596-05) were used according to the manufacturer’s instructions.

Techniques: Permeability, Adoptive Transfer Assay, Derivative Assay, Staining, Real-time Polymerase Chain Reaction