Abstract: Human and animal serum contains naturally occurring autoantibodies that develop at birth in absence of deliberate immunization. These antibodies are predominantly of IgM isotype but can include all immunoglobulin isotypes such as IgD, IgA and IgG. Here we describe IgM anti-lymphocyte autoantibodies (IgM-ALA) and show that these antibodies are heterogenous with some antibodies binding to chemokine receptors such as CCR5 and CXCR4 and others binding to other lymphocyte receptors including CD3, CD2, CD4 and CD81. These IgM-ALA, unlike IgG antibodies, are not cytolytic to cells at 37 C and hence function to alter lymphocyte function including cytokine production and act as “blocking antibodies to inhibit binding of chemokines and viruses including HIV-1 and Hepatitis C. IgM antibodies that bind to receptors on lymphocyte also bind to the same or similar class of receptors on other leucocytes and other cells such as cancer cells and endothelial cells.

Abstract: Human and animal serum contains naturally occurring autoantibodies that develop at birth in absence of deliberate immunization. These antibodies are predominantly of IgM isotype but can include all immunoglobulin isotypes such as IgD, IgA and IgG. Here we describe IgM anti-lymphocyte autoantibodies (IgM-ALA) and show that these antibodies are heterogenous with some antibodies binding to chemokine receptors such as CCR5 and CXCR4 and others binding to other lymphocyte receptors including CD3, CD2, CD4 and CD81. These IgM-ALA, unlike IgG antibodies, are not cytolytic to cells at 37 C and hence function to alter lymphocyte function including cytokine production and act as “blocking antibodies to inhibit binding of chemokines and viruses including HIV-1 and Hepatitis C. IgM antibodies that bind to receptors on lymphocyte also bind to the same or similar class of receptors on other leucocytes and other cells such as cancer cells and endothelial cells.

Abstract: In this invention, the inventor discloses that naturally occurring IgM anti-lymphocyte antibodies bind to chemokine and non-chemokine receptors on lymphocytes and other cells, and downmodulate certain receptors including CD4 and CD2 on T cells and CD80 and CD86 on macrophages. The inventor also discloses that such antibodies (i) inhibit HIV-1 and other viruses from infecting cells (ii) inhibits activation and proliferation of T lymphocytes (iii) inhibits cytokine and chemokine production (iv) inhibits inflammatory processes, and (v) enhances death of malignant cells. This art or invention is novel in that the antibodies described herein are “naturally occurring” i.e. develop in absence of deliberate immunization and secondly these antibodies are distinct from disease causing autoantibodies in that these naturally occurring antibodies are polyreactive with low binding affinity.