What It Is. An IgA test measures the blood level of immunoglobulin A, one of the most common antibodies in the body. Antibodies are proteins made by the immune system to fight bacteria, viruses, and toxins. IgA is found in high concentrations in the body's mucous membranes, particularly the respiratory passages and gastrointestinal tract, as well as in saliva and tears. IgA also plays a role in allergic reactions.
The highest recorded closing of the Dow Jones Industrial Average, as of 2015, is 18,312.39, according to FedPrimeRate.com. The DJIA crossed the 18,000 mark for the first time in December, 2014, and reached its current record in May, 2015. Continue Reading.
Stocks Break New Record As S&P 500 Closes At Highest Level Ever. The stock market is firing on all-cylinders, and about three weeks after the Dow topped its all-time high, the S&P 500 hit its highest closing price ever in early trading on Thursday and sustained the gains through the day.