Anti-beta-endorphin immunoglobulin G in humans.

Abstract

Human IgG specific for (8-endorphin was identified by enzyme-linked immunoabsorbent assay and isolated by affinity chromatography. From a sample of 27 subjects, three individuals with major depression demonstrated plasma IgG highly reactive with human 13-endorphin, while four other subjects (two with depression and two randomly selected blood donors) had intermediate reactivity. An enzyme-linked immunoabsorbent assay (ELISA) system was used to detect human and rabbit antibodies to 3-endorphin. In preliminary studies, the sensitivity and specificity of this assay was examined using rabbit anti-pendorphin antiserum (Immuno Nuclear, Stillwater, MN). This antiserum was found to have relatively high specificity for ,-endorphin with negligible reactivity to bovine plasma albumin (<3.5%) or other human neuropeptides (2.5-7.9%). In similar experiments, comparable specificity was found using antisera to other neuropeptides including corticotropin, a-melanotropin, and substance P, firmly establishing that each of these neuropeptides bound to ELISA plates (data not shown). In these preliminary studies, no data were available for human antibodies directed against neuropeptides. Using the rabbit anti-/3-endorphin antibody, we detected lowest reactivity against substance P and corticotropin and decided to use these as background for the human studies. MATERIALS AND METHODSImmunoglobulins. We examined purified IgG after either ammonium sulfate precipitation or protein A (Staphylococcus aureus) column separation. Serum samples were obtained from a general pool of6 blood donors, 9 healthy normal volunteers, and 12 psychiatric patients meeting Diagnostic and Statistical Manual of Mental Disorders III (13) criteria for either major depression (n = 9) or personality disorder (n = 3) who were sequentially admitted over a several-month period to a National Institute of Mental Health Clinical Center psychiatric unit. One of the subjects with major depression (subject 10) had a 1-year history of chronic pain and a prior history of an urticarial reaction to hydromorphone hydrochloride.ELISA. P-Endorphin (10 gg/ml) and substance P or corticotropin (10 ,g/ml) in pH 9.4 coating buffer were pipetted in a 100-,ul volume into an Immulon I polystyrene plate (Dynatech, New York) and allowed to stand at 0C for 48 hr. The plate was washed with 0.5% Tween 20 (Fisher) in phosphate-buffered saline (PBS; pH 7.3, without calcium or magnesium), and nonspecific binding sites were blocked with 100 ,ul of 0.5% bovine plasma albumin in distilled water for 20 min at room temperature. Then 100 41. of human IgG was added and incubated at 370C for 2 hr. The plate was then washed, and 100 ,1u of a 1:200 dilution of an alkaline phosphatase-conjugated goat anti-human Fc IgG (heavychain specific) antibody (Sigma) was pipetted into each well.After 2 hr at 37°C, the plate was washed, 100 ,u1 of the alkaline phosphatase substrate p-nitrophenyl phosphate (disodium salt) dissolved in 10% diethanolamine was added to each well, and the reaction was allowed to pro...

Functional IgG Autoantibodies against Autonomic Nervous System Receptors in Symptomatic Women with Silicone Breast Implants

“…It is worth mentioning that dysregulated autoantibodies targeting neurotransmitter receptors or other neuronal antigens have been linked to major depressive disorders (MDD) [46,47]. For example, numerous reports had linked anti-opioid receptor (OPRM1) IgG autoantibodies [48], antibodies to 5HT-1A or 5-hydroxytryptamine receptor 1A (HTR-1A), DRD2, and antibodies directed against the GPCR muscarinic cholinergic receptor 1 (CHRM1), to MDD [49]. Not surprisingly, the comorbidity of MDD and autoimmune diseases has been reported.…”

Human psychoneuroimmunology today

“…The somewhat increased incidence of autoantibodies in depressives is nonspecific (221,222). It is interesting that an IgG directed against beta-endorphin has been detected in the plasma of depressive patients more frequently than in healthy controls (222), but the significance of this finding is presently unclear.…”

Autoantibodies in Neuropsychiatric Disorders

“…Roy et al were the first to report high reactivity of anti-opioid receptor (OPRM1) IgG autoantibodies in 3 out of 27 patients with MDD [170]. In a later study by the same group, patient serum IgGs were isolated by affinity chromatography and analyzed for reactivity on rat brain tissue [150].…”