Two-dimensional polyacrylamide gel electrophoresis analysis of cryoglobulins and identification of an IgM-associated peptide.

The clonality of immunoglobulins (Igs) in cryoprecipitates (n = 41) was studied by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Our series included 24 cryoglobulins characterized by immunofixation electrophoresis (IF), 12 'trace amount' cryoglobulins, defined by a protein content in the precipitate of less than 0.05 mg/ml of serum, and five cryoglobulins of undetermined protein composition by IF.

No evidence for protein modifications in fresh frozen plasma after photochemical treatment: an analysis by high-resolution two-dimensional electrophoresis.

To study if photochemical treatment of human plasma by methylene blue in combination with visible light induces protein alterations, we analysed by high-resolution two-dimensional gel electrophoresis (2-D PAGE) untreated and photochemically treated fresh frozen plasma collected by apheresis from the same donor (n = 8). Polypeptides were separated according to their charges by isoelectric focusing and to their sizes in polyacrylamide gels in presence of sodium and to their sizes in polyacrylamide gels in presence of sodium dodecyl sulphate, and visualized by silver staining. Despite their apparent complexity, protein maps of untreated plasma and photochemically treated fresh frozen plasma revealed identical spot patterns.

Two-dimensional electrophoresis as an aid in the analysis of the clonality of immunoglobulins.

In this paper, we summarize our five-year observation of two-dimensional polyacrylamide gel electrophoretic (2-D PAGE) analysis of immunoglobulin (Ig) light (L) chain patterns on serum/plasma and/or purified human Ig, and compare this technique with agarose electrophoresis and/or immunofixation examination. Polyclonal Ig L chains were seen as large "fuzzy" areas with several zones of high density. The majority (71%) of the monoclonal Ig L chains of monoclonal gammopathy detected by conventional electrophoresis appeared as a single large and well-defined spot on 2-D PAGE analysis, with the remaining appearing as multiple spots.

Pattern variations of polyclonal and monoclonal immunoglobulins of different isotypes analyzed by high-resolution two-dimensional electrophoresis.

High-resolution two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was used to analyze serum samples and purified immunoglobulins (Ig) obtained from "normal" individuals and from patients diagnosed with monoclonal gammopathies (MG) (n = 47; 5 IgA, 15 IgM, 15 IgG, 4 biclonal IgG, 1 IgD, 7 Bence Jones proteins). Polyclonal and monoclonal heavy (H) chains were located at different restricted gel positions according to their isotype. Monoclonal H chains appeared as sets of spots characterized by charge (pI) and size (M(r)) microheterogeneity.

[Transient episode of erythrocytic autoimmunization in a patient alloimmunized at the end of multiple transfusions].

Delayed hemolytic reaction is a well recognized hazard of blood transfusion and occurs mainly in recipients with alloantibodies, due to sensitization to red cell antigens by previous transfusion or pregnancy. Less frequently, such a reaction may be associated with the presence of red cell autoantibodies appearing after alloimmunization. We report the observation of a patient with chronic myelomonocytic leukemia, who presented a transitory episode of delayed hemolysis after multiple transfusions.

[Two-dimensional electrophoretic study of monoclonal gammopathies and cold agglutinins associated with a chronic hemolytic anemia].

Two-dimensional gel electrophoresis (2-DGE) associated with a very sensitive silver staining is one of the most powerful technique available for protein analysis. Proteins are separated in the first dimension by isoelectric focusing in a pH gradient, and in the second dimension by polyacrylamide gel electrophoresis. Proteins are thus separated according to their charge and to their size.