Jin A, Ozawa T, Tajiri K, Obata T, Kishi H, Muraguchi A (2011):
“Rapid isolation of antigen-specific antibody secreting cells using a chip-based immunospot array”. Nature Protocols 6(5): 668-76.
This excellent publication describes what the authors call the ‘immunospot array assay on a chip’ (ISAAC), an advanced ELISpot assay to detect and retrieve IgG secreting peripheral lymphocytes on a single cell level. According to Jin et al, up to 234,000 individual cells can be analyzed within a day. First, anti human IgG antibodies are coupled to a microarray chip surface comprising 90,000 wells á 10 µm Ø. Immunized lymphocytes are isolated from peripheral blood, and subjected to the microwell chip, which should separate the lymphocytes by a single cell per well. Cell secreting IgGs specific for an antigen are detected by staining of the same with labelled antigen. Microcapillaries are finally used to retrieve the cells of interest. The method has several advantages:
1. Identification and production of human antibody therapeutics;
2. Screening of immunotherapeutic libraries for best immunostimulatory candidates;
3. Identification of a therapeutic antibody panel for the treatment of virus surfaces;
4. In vitro immunization of a lymphocyte population immobilized on the chip;
A great progress in immunology assay development in a high throughput nanoscale format.