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Biology subjects

Aslam, R.

Publications and source records attributed to Aslam, R..

2 recordsLinked to original sources

SeqStain using fluorescent-DNA conjugated antibodies allows efficient, multiplexed, spatialomic profiling of human and murine tissues

Spatial organization of molecules and cells in complex tissue microenvironments provides essential cues during healthy growth and in disease. Novel techniques are needed for elucidation of their spatial relationships and architecture. Although a few multiplex immunofluorescence based techniques have been developed for visualization of the spatial relationships of various molecules in cells and tissues, there remains a significant need for newer methods that are rapid, easy to adapt and are gentle during the cyclic steps of fluorescence staining and de-staining. Here, we describe a novel, multiplex immunofluorescence imaging method, termed SeqStain, that uses fluorescent-DNA labelled antibodies for immunofluorescence staining of cells and tissues, and nuclease treatment for de-staining that allows selective enzymatic removal of the fluorescent signal. SeqStain can be used with primary antibodies, secondary antibodies and antibody fragments, such as Fabs, to efficiently analyse complex cells and tissues in multiple rounds of staining and de-staining. Additionally, incorporation of specific endonuclease restriction sites in antibody labels allows for selective removal of fluorescent signals, while retaining other signals that can serve as marks for subsequent analyses. The application of SeqStain on human kidney tissue provided spatialomic profile of the organization of >25 markers in the kidney, highlighting it as a versatile, easy to use and gentle new technique for spatialomic analyses of complex microenvironments.

molecular biology↗

Apolipoprotein L1 Dynamics in Human Parietal Epithelial Cell Molecular Phenotype Kinetics

Human Parietal Epithelial cells (PECs) are considered as a source of progenitor cells to sustain podocyte (PD) homeostasis. We hypothesized that the absence of apolipoprotein (APO) L1 favors the PEC phenotype and that induction of APOL1 transitions to PD renewal. During PECs transition, APOL1 expression coincided with the expression of PD markers (PEC transition) along with down regulation of miR193a. The induction of APOL1 down regulated miR193a and induced PD markers in PECs/HEKs; whereas, the APOL1-silencing in transited (Tr)-PECs/HepG2s up regulated miR193a expression suggesting a reciprocally linked feedback loop relationship between APOL1 and miR193a. HIV, IFN-y, and vitamin D receptor agonist (VDA) induced APOL1 expression and PEC transition markers but down regulated miR193a in PECs/HEKs. Glomeruli in HIV patients and HIV: APOL1 transgenic mice displayed foci of PECs expressing synaptopodin, a PEC transition marker. Since APOL1 silencing in PECs partially attenuated HIV-, VDA-, and IFN-y-induced PECs transition, this would suggest that APOL1 is an important functional constituent of APOL1-miR193a axis.

molecular biology↗