Simultaneous analysis of serum immunoglobulins in patients with M protein using cellulose acetate membrane isoelectric focusing

Abstract

We developed a method for the simultaneous analysis of microheterogeneity of human serum IgG, IgA, IgM, IgD, and IgE, and serum protein pattern using cellulose acetate membrane isoelectric focusing, and analyzed in 11 healthy subjects and 67 patients with M protein (17 cases of multiple myeloma [MM] and 50 cases of monoclonal gammopathy of undetermined significance [MGUS]). Using this method, bands indicating the microheterogeneity of each immunoglobulin could clearly be detected. Among healthy subjects, the detected IgG, IgA, and IgM bands did not vary, but the detected IgE and IgD bands did vary. Therefore, IgA, IgM, and IgG were selected for comparison of serum immunoglobulins in MM and in MGUS. In the IgA‐type M protein group, normal IgM and IgG bands were decreased in MM patients compared to MGUS patients, while the M band and other bands were increased in MM patients compared to MGUS patients, but the differences between the two groups were not significant. In the IgG‐type M protein group, normal IgM, IgA, and IgG were significantly decreased in MM patients compared to MGUS patients. We examined the changes in electrophoretic pattern in six MM patients and eight MGUS patients with IgA‐type M protein after neuraminidase treatment. The width of the M band in MM patients with IgA‐type M protein decreased with neuraminidase treatment. On the other hand, the width of the M band in MGUS patients with IgA‐type M protein increased with neuraminidase treatment. We concluded that the decrease of the normal immunoglobulins in MM patients with IgG type M protein could be detected by this method, and IgA type of M protein binding sugar chain were different between MM and MGUS patients. J. Clin. Lab. Anal. 13:145–150, 1999. © 1999 Wiley‐Liss, Inc.

In Vitro Selection of High-Affinity DNA Ligands for Human IgE Using Capillary Electrophoresis

“…Although the peak shape was poor, excellent separation was still achieved between the uncomplexed DNA sequences and the IgE complex. The p I of human IgE is ∼9, 1 pH unit higher than the CE separation buffer. Therefore, IgE is slightly positive at the separation pH, dramatically slowing the mobility of the negative DNA upon binding.…”

Serum protein fractionation using supported molecular matrix electrophoresis

“…Immunostaining of proteins on cellulose acetate membranes usually involves fixation via acid treatment with sulfosalicylic acid or trichloroacetic acid . Immunostaining of SMME membranes, however, does not require acid fixation.…”