The Measurement of Immunoglobulin Associated with Human Peripheral Lymphocytes

A sensitive and reproducible technique for the quantitation of cell-associated Ig has been described. In a normal individual the amount of Ig associated with circulating peripheral lymphocytes seems to be quite constant over a 30 min period but varies widely over daily intervals. In normal individuals, most of the Ig associated with intact cells can be accounted for by circulating peripheral lymphocytes. There is some evidence to indicate that significant amounts of Ig may be released from peripheral leukocytes after freezing and thawing, suggesting that other cellular elements are involved. The Ig associated with circulating peripheral lymphocytes was either free within the cell or loosely bound to membranous portions of the cell. Radioactive labeled protein isolated from circulating lymphocytes revealed the major immunoglobulin in a normal individual to be IgG. Human albumin was also found in normal peripheral lymphocytes using similar techniques. The function of albumin in circulating peripheral leukocytes is unknown.