A monoclonal antibody raised against a synthetic oxytocin peptide stains mouse hypothalamic neurones

Abstract

A monoclonal antibody against oxytocin was generated in 7a5 hybridoma cells derived from myeloma cells and lymphocytes from the spleen of mice immunised with a synthetic oxytocin peptide. The 7a5 monoclonal antibody bound with oxytocin in enzyme‐linked immunosorbent assays. 7a5 cell growth medium was diluted up to 5000‐fold and used for immunohistochemistry. First, to test the specificity of the 7a5 antibody against oxytocin, we stained brain tissues of oxytocin knockout mice, comprising mice in which the first exon of the oxytocin‐neurophysin gene is deleted. No 7a5 immunoreactivity was detected in the paraventricular nucleus (PVN) of the hypothalamus of oxytocin knockout mice; however, this area was strongly stained with the anti‐vasopressin polyclonal antibody, HM07. Tissue preparations of the wild‐type mouse PVN and supraoptic nucleus (SON) displayed 7a5 immunoreactivity that was indistinguishable from the staining produced with an anti‐oxytocin polyclonal antibody, HM06. The immunoreactivity of HM06 in the PVN was similar to that of an anti‐oxytocin monoclonal antibody, PS38. We then examined the cross‐reactivity of 7a5 with arginine vasopressin. The majority of cell soma and processes stained by 7a5 were not co‐stained with the vasopressin antibody in SON and PVN regions. Furthermore, the suprachiasmatic nucleus was stained by the vasopressin antibody but not by 7a5. These results demonstrate that 7a5 is a new anti‐oxytocin monoclonal antibody recognising oxytocin and not vasopressin; therefore, 7a5 can be used to investigate the role of oxytocin in the brain.

Identification of peripheral oxytocin‐expressing cells using systemically applied cell‐type specific adeno‐associated viral vector

“…Whether expression of the oxytocin gene, as reflected by Venus expression, is consistently accompanied by the expression of biologically active oxytocin remains to be determined because the antibody against the oxytocin‐associated neurophysin used in the present study recognises both the precursor and mature forms of neurophysin 35 . Further studies should consider the use of specific antibodies targeting the (bioactive) oxytocin nonapeptide as reported recently, 63 and the use of oxytocin‐deficient animals as an additional (negative) control for Venus and oxytocin‐neurophysin labelling in peripheral tissues.…”

A comprehensive overview of the relationship between RET gene and tumor occurrence

“…HM06, another selective RET inhibitor, circumvents RET-V804X gatekeeper mutation and RET-G810X resistance mutations. This drug is currently in phase I/II clinical trials (NCT04683250) in a patient with RET mutation ( 75 ). Lastly, LOX-18228 can inhibit RET-V804X and RET-G810X mutations, which have a promising use after first-generation RET inhibitors.…”

Advances in neurohypophysial hormones research

“…A complementary study by Freeman and colleagues compares the distribution of central OXT and AVP receptors among different rodent species, in an effort to localise conserved sites of action of the neurohypophysial hormones in the brain 7 . To complete the set of neuroanatomical papers, Kogami and colleagues describe a new OXT‐specific monoclonal antibody, thus adding an important reagent to OXT‐related research 8 …”