Human immunoprotein consists of two identical heavy chains (about 50kD) and two identical light chains, connected by disulfur linkage, the light chains are κ or λ, The heavy chains of the five immunoglobulins of IgA, IgD, IgE, IgG and IgM are different. IgA and lgM differs are because they can form polypolymers, IgG heavy chain is a γ chain.Human IgG consists of four sub-classes, with only slightly different amino acids. IgG antibodies are reported to be used to identify the classification of plasma cells containing IgG, lymphocytes, and B-cell-derived tumors. Normal B cell population is polyclonal, expressing a range of different immunoglobulins. In contrast, most B-cell tumors are characterized by monoclonal cell proliferation, expressing a light chain, while the same cell can express more than one heavy chain.IgG-positive tumors include hair cell leukemia, spleen lymphoma, and follicle lymphoma.