Browsing by Subject "ELISA"

Now showing 1 - 3 of 3
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    Antiphospholipid autoantibodies as blood biomarkers for detection of early stage Alzheimer's disease
    (Taylor & Francis, 2015-08) McIntyre, John A.; Ramsey, Curtis J.; Gitter, Bruce D.; Saykin, Andrew J.; Wagenknecht, Dawn R.; Hyslop, Paul A.; Department of Radiology and Imaging Sciences, IU School of Medicine
    A robust blood biomarker is urgently needed to facilitate early prognosis for those at risk for Alzheimer's disease (AD). Redox reactive autoantibodies (R-RAAs) represent a novel family of antibodies detectable only after exposure of cerebrospinal fluid (CSF), serum, plasma or immunoglobulin fractions to oxidizing agents. We have previously reported that R-RAA antiphospholipid antibodies (aPLs) are significantly decreased in the CSF and serum of AD patients compared to healthy controls (HCs). These studies were extended to measure R-RAA aPL in serum samples obtained from Alzheimer's Disease Neuroimaging Initiative (ADNI). Serum samples from the ADNI-1 diagnostic groups from participants with mild cognitive impairment (MCI), AD and HCs were blinded for diagnosis and analyzed for R-RAA aPL by ELISA. Demographics, cognitive data at baseline and yearly follow-up were subsequently provided by ADNI after posting assay data. As observed in CSF, R-RAA aPL in sera from the AD diagnostic group were significantly reduced compared to HC. However, the sera from the MCI population contained significantly elevated R-RAA aPL activity relative to AD patient and/or HC sera. The data presented in this study indicate that R-RAA aPL show promise as a blood biomarker for detection of early AD, and warrant replication in a larger sample. Longitudinal testing of an individual for increases in R-RAA aPL over a previously established baseline may serve as a useful early sero-epidemiologic blood biomarker for individuals at risk for developing dementia of the Alzheimer's type.
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    CD30 Lateral Flow and Enzyme-Linked Immunosorbent Assays for Detection of BIA-ALCL: A Pilot Study
    (MDPI, 2023-10-25) Zeyl, Victoria G.; Xu, Haiying; Khan, Imran; Machan, Jason T.; Clemens, Mark W.; Hu, Honghua; Deva, Anand; Glicksman, Caroline; McGuire, Patricia; Adams, William P., Jr.; Sieber, David; Sinha, Mithun; Kadin, Marshall E.; Surgery, School of Medicine
    Introduction: Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) commonly presents as a peri-implant effusion (seroma). CD30 (TNFRSF8) is a consistent marker of tumor cells but also can be expressed by activated lymphocytes in benign seromas. Diagnosis of BIA-ALCL currently includes cytology and detection of CD30 by immunohistochemistry or flow cytometry, but these studies require specialized equipment and pathologists' interpretation. We hypothesized that a CD30 lateral flow assay (LFA) could provide a less costly rapid test for soluble CD30 that eventually could be used by non-specialized personnel for point-of-care diagnosis of BIA-ALCL. Methods: We performed LFA for CD30 and enzyme-linked immunosorbent assay (ELISA) for 15 patients with pathologically confirmed BIA-ALCL and 10 patients with benign seromas. To determine the dynamic range of CD30 detection by LFA, we added recombinant CD30 protein to universal buffer at seven different concentrations ranging from 125 pg/mL to 10,000 pg/mL. We then performed LFA for CD30 on cryopreserved seromas of 10 patients with pathologically confirmed BIA-ALCL and 10 patients with benign seromas. Results: Recombinant CD30 protein added to universal buffer produced a distinct test line at concentrations higher than 1000 pg/mL and faint test lines at 250-500 pg/mL. LFA produced a positive test line for all BIA-ALCL seromas undiluted and for 8 of 10 malignant seromas at 1:10 dilution, whereas 3 of 10 benign seromas were positive undiluted but all were negative at 1:10 dilution. Undiluted CD30 LFA had a sensitivity of 100.00%, specificity of 70.00%, positive predictive value of 76.92%, and negative predictive value of 100.00% for BIA-ALCL. When specimens were diluted 1:10, sensitivity was reduced to 80.00% but specificity and positive predictive values increased to 100.00%, while negative predictive value was reduced to 88.33%. When measured by ELISA, CD30 was below 1200 pg/mL in each of six benign seromas, whereas seven BIA-ALCL seromas contained CD30 levels > 2300 pg/mL, in all but one case calculated from dilutions of 1:10 or 1:50. Conclusions: BIA-ALCL seromas can be distinguished from benign seromas by CD30 ELISA and LFA, but LFA requires less time (<20 min) and can be performed without special equipment by non-specialized personnel, suggesting future point-of-care testing for BIA-ALCL may be feasible.
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    Establishment of sandwich ELISA for soluble alpha-Klotho measurement: Age-dependent change of soluble alpha-Klotho levels in healthy subjects
    (2010-07) Yamazaki, Yuji; Imura, Akihiro; Urakawa, Itaru; Shimada, Takashi; Murakami, Junko; Aono, Yukiko; Hasegawa, Hisashi; Yamashita, Takeyoshi; Nakatani, Kimihiko; Saito, Yoshihiko; Okamoto, Nozomi; Kurumatani, Norio; Namba, Noriyuki; Kitaoka, Taichi; Ozono, Keiichi; Sakai, Tomoyuki; Hataya, Hiroshi; Ichikawa, Shoji; Imel, Erik A.; Econs, Michael J.; Nabeshima, Yo-ichi
    Background α-Klotho (αKl) regulates mineral metabolism such as calcium ion (Ca2+) and inorganic phosphate (Pi) in circulation. Defects in mice result in clinical features resembling disorders found in human aging. Although the importance of transmembrane-type αKl has been demonstrated, less is known regarding the physiological importance of soluble-type αKl (sαKl) in circulation. Objectives The aims of this study were: (1) to establish a sandwich ELISA system enabling detection of circulating serum sαKl, and (2) to determine reference values for sαKl serum levels and relationship to indices of renal function, mineral metabolism, age and sex in healthy subjects. Results We successively developed an ELISA to measure serum sαKl in healthy volunteers (n = 142, males 66) of ages (61.1 ± 18.5 year). The levels (mean ± SD) in these healthy control adults were as follows: total calcium (Ca; 9.46 ± 0.41 mg/dL), Pi (3.63 ± 0.51 mg/dL), blood urea nitrogen (BUN; 15.7 ± 4.3 mg/dL), creatinine (Cre; 0.69 ± 0.14 mg/dL), 1,25 dihydroxyvitamin D (1,25(OH)2D; 54.8 ± 17.7 pg/mL), intact parathyroid hormone (iPTH; 49.2 ± 20.6 pg/mL), calcitonin (26.0 ± 12.3 pg/mL) and intact fibroblast growth factor (FGF23; 43.8 ± 17.6 pg/mL). Serum levels of sαKl ranged from 239 to 1266 pg/mL (mean ± SD; 562 ± 146 pg/mL) in normal adults. Although sαKl levels were not modified by gender or indices of mineral metabolism, sαKl levels were inversely related to Cre and age. However, sαKl levels in normal children (n = 39, males 23, mean ± SD; 7.1 ± 4.8 years) were significantly higher (mean ± SD; 952 ± 282 pg/mL) than those in adults (mean ± SD; 562 ± 146, P < 0.001). A multivariate linear regression analysis including children and adults in this study demonstrated that sαKl correlated negatively with age and Ca, and positively with Pi. Finally, we measured a serum sαKl from a patient with severe tumoral calcinosis derived from a homozygous missense mutation of α-klotho gene. In this patient, sαKl level was notably lower than those of age-matched controls. Conclusion We established a detection system to measure human serum sαKl for the first time. Age, Ca and Pi seem to influence serum sαKl levels in a normal population. This detection system should be an excellent tool for investigating sαKl functions in mineral metabolism.