id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-334165-7gfk554m	Stadlbauer, Daniel	SARS‐CoV‐2 Seroconversion in Humans: A Detailed Protocol for a Serological Assay, Antigen Production, and Test Setup	2020-04-17		.txt	text/plain	5286	414	69	Basic Protocol 1: Mammalian cell transfection and protein purification Basic Protocol 2: A two‐stage ELISA for high‐throughput screening of human serum samples for antibodies binding to the spike protein of SARS‐CoV‐2 We reported in our earlier work that individuals not exposed to SARS-CoV-2 are completely naïve to the spike protein, and their serum samples show little or no reactivity in an ELISA (Amanat et al., 2020) . We developed this as a two-stage ELISA in which the first stage ('a' steps below) includes relatively high-throughput screening of samples in a single serum dilution against the RBD (which expresses very well and therefore can be produced in greater quantities). This is followed by a second stage ('b' steps below) in which positive samples from the first stage undergo a confirmatory ELISA against the full-length spike protein (which is harder to express; therefore there is usually less available). i. Thaw the required number of vials of antigen (SARS-CoV-2 RBD protein) to coat 96-well microtiter ELISA plates at a concentration of 2 μg/ml.	./cache/cord-334165-7gfk554m.txt	./txt/cord-334165-7gfk554m.txt