Naturally occurring autoantibodies (NAbs) are common in normal humans. The majority of NAbs are IgMs, but a small proportion are IgGs. Therefore a certain portion of pooled whole human IgG (IVIG) can be considered NAbs. While the applications of IVIG to modulate human disease have increased dramatically, the use of IgMs as drugs has lagged. In fact, much of the contaminating IgM component of IVIG is disposed of as waste. However, a number of model studies, including those targeting Alzheimer and multiple sclerosis (MS) suggest that IgMs may better modulate disease at much lower doses than IVIG. Our own studies in a model of MS show that polyclonal human IgM promotes better remyelination than IVIG and that monoclonal IgMs promote greater remyelination than monoclonal IgGs containing identical variable region sequences. We propose that this difference is due to the ability of IgM to cross link cell surface antigens better than IgGs and induce signals in nervous system cells. Monoclonal antibodies (mAbs) that promote remyelination induce a transient Ca2+ influx in myelin forming cells, whereas IgGs with identical variable sequences do not. MAbs that promote remyelination were identified in human serum and in EBV‑immortalized human B‑cell lines obtained from normal adults, fetal cord blood, and rheumatoid arthritis and MS patients. Therefore therapeutic mAbs are present and common in normal circulation. All therapeutic mAbs were IgMs and bound to nervous system cells, however, the tissue binding patterns suggest that binding any one of multiple antigens induces repair. An expression vector was constructed that can manufacture gram quantities of recombinant monoclonal human IgM. Therefore the technology exists to determine whether human monoclonal NAbs can modulate human disease. IVIG can modulate neurologic disease, but using IVIG to treat these chronic diseases is unsustainable. A long‑term solution is to identify the functional component of IVIG and test whether a recombinant human monoclonal can replicate its efficacy.
Ischemia and reperfusion events within the heart and brain and similar trauma‑induced ischemia/reperfusion events lead to significant morbidity and mortality. In the past two decades, an excessive innate immune response has been identified as the mediator of reperfusion‑induced tissue...
Polyspecificity (polyreactivity) is currently considered an intrinsic property of a subset of antibodies, primarily of naturally occurring autoantibodies. Polyspecificity is no longer viewed as a biologically irrelevant stickiness. Furthermore, the capacity to bind defined sets of unrelated...
Germline‑encoded naturally occurring autoantibodies (NAbs) developed about 400 to 450 million years ago to provide specificity for clearance of body waste in animals with 3 germ layers. Such NAbs became a necessity to selectively clear aged red blood cells (RBC) surviving 60 to 120 d in...
Subsets of IgM naturally occurring autoantibodies (NAbs) bind to the cell surface membranes of dying cells. The antibodies predominantly have specificities against lipid antigens or oxidized lipids. Chief among these lipid antigens are phosphorylcholine (PC) and malondialdehyde (MDA)....
Naturally occurring autoantibodies (NAbs) are common in normal humans. The majority of NAbs are IgMs, but a small proportion are IgGs. Therefore a certain portion of pooled whole human IgG (IVIG) can be considered NAbs. While the applications of IVIG to modulate human disease have increased...
Healthy persons carry within their pool of circulating antibodies immunoglobulins preferentially of IgM isotype, which are directed against a variety of tumor‑associated antigens. In closer scrutiny of their nature, some of these antibodies could be defined as naturally occurring antibodies...
Naturally occurring antibodies (NAbs) have specificity for both microbial and self antigens, which allows them to act in the first line defense against invading pathogens, as well as in tissue homeostasis by mediating the clearance of cellular debris. This latter recognition of self by NAbs...
Programmed cell death (PCD) plays a central role in the regulation of granulocytes that are key effector cells of the innate immune system. Granulocytes are produced in high amounts in the bone marrow. A safe elimination of granulocytes by cell death (apoptosis) is essential to maintain the...
Naturally occurring antibodies (NAbs) play a vital role in the first line of defense against bacterial and viral infections. Most studies in mice and man have attributed this role to NAbs of the IgM isotype. However, there is also a significant amount of data on the anti‑infectious function...
Antibody networks have been studied in the past based on the connectivity between idiotypes and anti‑idiotypes—antibodies that bind one another. Here we call attention to a different network of antibodies, antibodies connected by their reactivities to sets of antigens—the...
The role of naturally occurring autoantibodies (NAbs) in homeostasis and in disease manifestations is poorly understood. In the present chapter, we review how NAbs may interfere with the cytokine network and how NAbs, through formation of complement‑activating immune complexes with soluble...
Naturally occurring autoantibodies (NAbs) are typically polyreactive, bind with low affinity to a discrete set of autoantigens and are encoded by variable region genes in germline configuration. They differ from disease‑associated autoantibodies (autoAb), which are mostly monoreactive,...
Most studies on the effects of naturally occurring autoantibodies (NAbs) on immune cells have been performed in the context of research on the immunomodulatory effects of intravenous immunoglobulin (IVIG). Among others, IVIG inhibits the differentiation, maturation and functions of dendritic...
In sepsis death follows an excessive inflammatory response involving cytokines and complement that is activated primarily via the amplifying C3/C5 convertase. Excessive stimulation of complement amplification requires IgG‑containing or F(ab’) 2 ‑containing immune complexes (IC) that...
Immunoglobulins (antibodies) frequently express constitutive functions. Two such functions are nucleophilic catalysis and the reversible binding to B‑cell superantigens. Constitutive or “naturally‑occurring” antibodies are produced spontaneously from germline genetic information. The...
Naturally occurring antibodies (NAbs) have been described for more than 30 years. Recently, NAbs against β‑Amyloid and against other proteins involved in neurodegenerative disorders have been detected in humans. Based on the current evidence, it is hypothesized that anti‑Aβ NAbs can...
It was a long way from the use of hyperimmune animal sera for the treatment of toxin‑producing infections to the production of polyclonal, polyspecific human immunoglobulin preparations and the use of NAbs as therapeutic tools for autoimmune and inflammatory diseases. Some highlights of the...
Naturally occurring antibodies (NAbs) produced by CD5+ B‑1 B cells include those with specificity for thymocytes (anti‑thymocyte autoantibody, ATA). Here we describe a prototypic example, encoded by an unmutated immunoglobulin μ/κ heavy chain/light chain. Studies with ATA‑μ (“heavy...