Genereren van tweekleurige Antigen Microarrays voor de simultane detectie van IgG en IgM Autoantistoffen

Summary

We describe here a method to generate customizable antigen microarrays that can be used for the simultaneous detection of serum IgG and IgM autoantibodies from humans and mice. These arrays allow for high-throughput and quantitative detection of antibodies against any antigens or epitopes of interest.

Abstract

Autoantibodies, which are antibodies against self-antigens, are present in many disease states and can serve as markers for disease activity. The levels of autoantibodies to specific antigens are typically detected with the enzyme-linked immunosorbent assay (ELISA) technique. However, screening for multiple autoantibodies with ELISA can be time-consuming and requires a large quantity of patient sample. The antigen microarray technique is an alternative method that can be used to screen for autoantibodies in a multiplex fashion. In this technique, antigens are arrayed onto specially coated microscope slides with a robotic microarrayer. The slides are probed with patient serum samples and subsequently fluorescent-labeled secondary antibodies are added to detect binding of serum autoantibodies to the antigens. The autoantibody reactivities are revealed and quantified by scanning the slides with a scanner that can detect fluorescent signals. Here we describe methods to generate custom antigen microarrays. Our current arrays are printed with 9 solid pins and can include up to 162 antigens spotted in duplicate. The arrays can be easily customized by changing the antigens in the source plate that is used by the microarrayer. We have developed a two-color secondary antibody detection scheme that can distinguish IgG and IgM reactivities on the same slide surface. The detection system has been optimized to study binding of human and murine autoantibodies.

Introduction

Autoantibodies are present in many disease states and can often have direct pathogenic activity¹. Identification of autoantibodies is important for diagnosis of certain diseases, for prognosis of disease outcome, and for the classification of patients who may benefit from specific therapies². Autoantibodies are typically identified in patient serum using the ELISA technique; however, screening for multiple antigens with this technique is laborious and consumes a large quantity of patient sample. New technologies are therefore needed to profile autoantibodies on a larger scale.

The antigen microarray technique is a prot....

Protocol

1. Verdunning antigenen en genereren Antigen Microarrays

1. Verdun antigenen in PBS tot een eindconcentratie van 0,2 mg / ml. Druk tot 162 unieke antigenen in tweevoud met een microarrayprinter configuratie met 9 pinnen. Onder IgG en IgM antigenen in het antigeen bibliotheek als positieve controles. Omvatten PBS alleen als een negatieve controle.
2. Voeg 20 ul van elk antigeen aan de 384 goed bronplaat. Antigenen toevoegen bronplaat in groepen die de instelling van de printkop spiegel (bv regelen antigenen in groepen van 9 bij 9 kunnen worden gebruikt voor het afdrukken).
3. Cover bron plaat met folie en bevriezen bij -80 ° C tot klaar ....

Results

Antigenen zijn aangebracht in een plaat met 384 putjes en gedrukt op objectglaasjes door een robot microarrayprinter zie figuur 1. Figuur 2 toont glaasjes geplaatst in een frame met incubatie kamers en een gescande dia na verwerking. Figuur 3 toont positieve en negatieve controleglaasjes. De negatieve schuif alleen maar geprobed met secundaire antilichamen, en de positieve controle dia geprobed met serum van een patiënt met systemische l.......

Discussion

De hier beschreven protocol maakt de kwantificering van auto-antilichamen met het antigeen microarray techniek. Antigeen microarrays bieden verscheidene voordelen boven conventionele ELISA screening voor autoantilichamen. Allereerst een grote antigenen zoals nucleïnezuren, eiwitten, peptiden, en cellysaten worden opgesteld op de met nitrocellulose gecoate glaasjes, hetgeen aldus gemultiplexte screenen van autoantilichamen. Bovendien, slechts microgram antigeen nodig om de arrays genereren aangezien nanoliters antigeendo.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Ribosomal P0	Diarect	14100	dilute to 0.2 mg/ml in PBS
human IgG	Jackson Immuno	009-000-003	dilute to 0.2 mg/ml in PBS
human IgM	Jackson Immuno	009-000-012	dilute to 0.2 mg/ml in PBS
mouse IgG	Sigma-Aldrich	I5381	dilute to 0.2 mg/ml in PBS
mouse IgM	Biolegend	401601	dilute to 0.2 mg/ml in PBS
double-stranded DNA	Sigma-Aldrich	D1626	dilute to 0.2 mg/ml in PBS
single-stranded DNA	Sigma-Aldrich	D8899	dilute to 0.2 mg/ml in PBS
microarrayer	Virtek	VersArray Chipwriter Pro	many types of arrayers are suitable
solid printing pins	Arrayit Corporation	SSP015
software for robotic microarrayer	Virtek	Chipwriter Pro
FAST slides (2 Pad)	GVS Northa America	10485317
FAST frame	GVS Northa America	10486001
FAST incubation chambers (2 Pad)	GVS Northa America	10486242
384 well plates	Whatman	7701-5101
plate sealers	VWR	60941-062
foil plate covers	VWR	60941-124
Tween-20	Fisher Scientific	BP337-500
Fetal calf serum	Invitrogen	12483020
Cy3 goat anti-human IgG	Jackson Immuno	109-165-096	use working stock in 50% glyercol
Cy5 goat anti-human IgM	Jackson Immuno	109-175-129	use working stock in 50% glyercol
Cy3 goat anti-mouse IgG	Jackson Immuno	115-165-071	use working stock in 50% glyercol
Cy5 goat anti-mouse IgM	Jackson Immuno	115-175-075	use working stock in 50% glyercol
Microarray Scanner	Molecular Devices	Axon 4200A
Microarray software	Molecular Devices	Genepix 6.1
Clustering software	eisenlab.org	Cluster 3.0
Heatmap software	eisenlab.org	Treeview 1.60
Microarray statistical software	Stanford University	SAM 4.0 (Significance Analysis of Microarrays)