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Surface Antigen Profiling of Helicobacter pylori-Infected and -Uninfected Gastric Cancer Cells Using Antibody Microarray

Sukri A, Hanafiah A, Kosai NR, Mohamed Taher M, Mohamed Rose I

Helicobacter, 2016 Oct;21(5):417-27.
PMID: 26807555 DOI: 10.1111/hel.12295

Comprehensive immunophenotyping cluster of differentiation (CD) antigens in gastric adenocarcinoma, specifically between Helicobacter pylori-infected and -uninfected gastric cancer patients by using DotScan(™) antibody microarray has not been conducted. Current immunophenotyping techniques include flow cytometry and immunohistochemistry are limited to the use of few antibodies for parallel examination. We used DotScan(™) antibody microarray consisting 144 CD antibodies to determine the distribution of CD antigens in gastric adenocarcinoma cells and to elucidate the effect of H. pylori infection toward CD antigen expression in gastric cancer.

Matched MeSH terms: Antigens, Surface/analysis*
Flow cytometric analysis of intracellular myeloperoxidase distinguishes lymphocytes, monocytes and granulocytes

Tay SP, Cheong SK, Hamidah NH, Ainoon O

Malays J Pathol, 1998 Dec;20(2):91-4.
PMID: 10879268

A study was undertaken to evaluate the ability of flow cytometric analysis of intracellular myeloperoxidase (MPO) in differentiating populations of lymphocytes (L), monocytes (M) and granulocytes (G), by means of lysed whole blood method. Anticoagulated blood from 23 normal individuals was lysed with FACS lysing solution and permeabilized with FACS permeabilizing solution before subjected to direct immunofluorescence staining. The geometric means of the fluorescence intensity were measured using FACSCalibur flow cytometer (Becton Dickinson). Populations of L, M and G were gated based on their light scatter characteristics and expression of CD14 and CD45. Then, the fluorescence intensity of MPO expression was studied in these individual cell populations. The results showed that fluorescence intensity of MPO was the strongest in G and weakest in L, whereas M showed intermediate fluorescence intensity. Our findings reveal that discrimination of these three cell types is achievable based upon the sole expression of intracellular MPO.

Matched MeSH terms: Antigens, Surface/analysis
Knob-positive and knob-negative Plasmodium falciparum differ in expression of a strain-specific malarial antigen on the surface of infected erythrocytes

Aley SB, Sherwood JA, Howard RJ

J. Exp. Med., 1984 Nov 01;160(5):1585-90.
PMID: 6208311

We have investigated the expression of a strain-specific malarial antigen on the surface of erythrocytes infected with knobless (K-) variants of knob-positive (K+) strains of Plasmodium falciparum. Aotus blood infected with K+ or K- parasites derived from two independent geographical isolates (Malayan camp and Santa Lucia) was surface iodinated by the lactoperoxidase method. Infected and uninfected erythrocytes were then separated by a new procedure involving equilibrium density sedimentation on a Percoll gradient containing sorbitol. Strain-specific antigens were readily identified on the surface of erythrocytes infected with either of the K+ strains by their characteristic size and detergent solubility. These proteins were not detected on the surface of erythrocytes infected with either of the K- variants nor on uninfected erythrocytes isolated from K+- or K- -infected blood. These results are consistent with a role for the strain-specific surface antigen in cytoadherence of P. falciparum-infected erythrocytes. Our findings represent the second biochemical difference (with the knob-associated histidine-rich protein) between K+ and K- P. falciparum.

Matched MeSH terms: Antigens, Surface/analysis*
Adult acute lymphoblastic leukaemia at University Hospital, Malaysia

Bosco JJ, Cherian R, Pang T

Haematol Blood Transfus, 1985;29:67-9.
PMID: 3861492
Matched MeSH terms: Antigens, Surface/analysis
Immunosensing prostate-specific antigen: Faradaic vs non-Faradaic electrochemical impedance spectroscopy analysis on interdigitated microelectrode device

Ibau C, Arshad MKM, Gopinath SCB, Nuzaihan M N M, Fathil MFM, Shamsuddin SA

Int J Biol Macromol, 2020 Nov 01;162:1924-1936.
PMID: 32822729 DOI: 10.1016/j.ijbiomac.2020.08.125

This work explores Electrochemical Impedance Spectroscopy (EIS) detection for a highly-sensitive quantification of prostate-specific antigen (PSA) in Faradaic (f-EIS) and non-Faradaic modes (nf-EIS). Immobilization of monoclonal antibody specific to PSA (anti-PSA) was performed using 1-ethyl-3-dimethylaminopropylcarbodiimide hydrochloride and N-hydroxysuccinimide crosslinking agents in order to conjugate carboxylic (-COOH) terminated group of 16-Mercaptoundecanoic acid with amine (-NH3+) on anti-PSA epitope. This approach offers simple and efficient approach to form a strong, covalently bound thiol-gold (SAu) for a reliable SAM layer formation. Studies on the topographic of pristine Au-IDE surface were performed by Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy techniques, meanwhile a 3-dimensional optical surface profiler, Atomic Force Microscopy and X-ray Photoelectron Spectroscopy techniques were used to validate the successful functionalization steps on the sensor transducer surface. Detection of PSA in f-EIS mode was carried out by measuring the response in charge transfer resistance (Rct) and impedance change (Z), meanwhile in nf-EIS mode, the changes in device capacitance was monitored. In f-EIS mode, the sensor reveals a logarithmic detection of PSA in a range of 100 ng/ml down to 0.01 ng/ml in Phosphate Buffered Saline with a recorded sensitivity of 2.412 kΩ/log10 ([PSA] ng/ml) and the limit of detection (LOD) down to 0.01 ng/ml. The nf-EIS detection mode yields a logarithmic detection range of 5000 ng/ml down to 0.5 ng/ml, with a sensitivity of 8.570 nF/log10 ([PSA] ng/ml) and an LOD of 0.5 ng/ml. The developed bio-assay yields great device stability, specificity to PSA and repeatability of detection that would pave its way for the future development into portable lab-on-chip bio-sensing system.

Matched MeSH terms: Antigens, Surface/analysis*
Interaction study of peptide-PAMAM as potential bio-nanogate for detecting anti-hepatitis B surface antigen

Syamila N, Syahir A, Ikeno S, Tan WS, Ahmad H, Ahmad Tajudin A

Colloids Surf B Biointerfaces, 2020 Jan 01;185:110623.
PMID: 31735420 DOI: 10.1016/j.colsurfb.2019.110623

Bio-nanogate involves synthesized or natural molecules as a 'gate' towards bioreceptors and responds upon the presence of targeted analytes in nanoscale dimension. Development of bio-nanogate improves analyte selectivity and signal response across various types of biosensors. The versatility of PAMAM dendrimers to form conjugates with guest molecules, such as proteins can be utilized in forming a bio-nanogate. PAMAM interaction with peptide bioreceptor for antibody detection is of interest in this study. This study investigated the interaction of synthesized immunogenic 'a' determinant (aD) region of hepatitis B virus surface antigen (HBsAg) with PAMAM G4 and anti-HBsAg antibody, as a potential bio-nanogate for anti-HBsAg detection. The aD peptide fused with maltose binding protein (MBP), was confirmed with Western blotting. Nano-Differential Scanning Fluorimetry (nano-DSF) study revealed that the interaction of MBP-aD with anti-HBsAg indicated a higher thermal stability as compared to its interaction with PAMAM G4. Electrochemical impedance spectroscopy showed that a higher binding constant of MBP-aD interaction with anti-HBsAg (0.92 μM-1) was observed at maximum saturation, as compared with PAMAM G4 (0.07 μM-1). Thermodynamic parameters demonstrated that MBP-aD interacted with anti-HBsAg and PAMAM G4, through van der Waals and hydrogen bonding. These analyses suggest that the weak interaction of MBP-aD and PAMAM G4 may form a potential bio-nanogate. It is hypothesized that the presence of anti-HBsAg has a higher affinity towards MBP-aD which may displace PAMAM G4 in the anti-HBsAg detection system. This interaction study is crucial as an initial platform of using peptide-PAMAM as a bio-nanogate in an antibody detection system.

Matched MeSH terms: Antigens, Surface/analysis*
Leukaemia and lymphoma in Malaysia

Bosco J, Cherian R, Lin HP, Pang T

Leuk. Res., 1985;9(6):789-91.
PMID: 3874337
Matched MeSH terms: Antigens, Surface/analysis
Human chorion-derived stem cells: changes in stem cell properties during serial passage

Fariha MM, Chua KH, Tan GC, Tan AE, Hayati AR

Cytotherapy, 2011 May;13(5):582-93.
PMID: 21231803 DOI: 10.3109/14653249.2010.549121

BACKGROUND AIMS: Fetal membrane from human placenta tissue has been described as a potential source of stem cells. Despite abundant literature on amnion stem cells, there are limited studies on the stem cell properties of chorion-derived stem cells.
METHODS: The main aim was to determine the stemness properties of serial-passaged human chorion-derived stem cells (hCDSC). Quantitative polymerase chain reaction (PCR) was performed to reveal the following stemness gene expression in serial-passaged hCDSC: Oct-4, Sox-2, FGF-4, Rex-1, TERT, Nanog (3), Nestin, FZD-9, ABCG-2 and BST-1. Cell growth rate was evaluated from passage (P) 1 until P5. The colony-forming unit-fibroblast (CFU-F) frequency of P3 and P5 cells and multilineage differentiation potential of P5 cells were determined. The immunophenotype of hCDSC was compared using the surface markers CD9, CD31, CD34, CD44, CD45, CD73, CD90, CD117, HLA-ABC and HLA-DR, -DP and -DQ. Immunostaining for trophoblast markers was done on P0, P1, P3 and P5 cells to detect the contamination of trophoblasts in culture, while chromosomal abnormality was screened by cytogenetic analysis of P5 cells.
RESULTS: The surface markers for mesenchymal lineage in hCDSC were more highly expressed at P5 compared with P3 and P0, indicating the increased purity of these stem cells after serial passage. Indeed, all the stemness genes except TERT were expressed at P1, P3 and P5 hCDSC. Furthermore, human chorion contained high clonogenic precursors with a 1:30 CFU-F frequency. Successful adipogenic, chondrogenic and osteogenic differentiation demonstrated the multilineage potential of hCDSC. The karyotyping analysis showed hCDSC maintained chromosomal stability after serial passage.
CONCLUSIONS: hCDSC retain multipotent potential even at later passages, hence are a promising source for cell therapy in the future.

Matched MeSH terms: Antigens, Surface/analysis