Apparent Functionality But Impractical Quantification of Neurotensin Receptors on Human Peripheral Lymphocytes

Abstract

Neurotensin (NT), a neuromodulator, is also thought to play an immunomodulatory role. We sought to confirm the effects of NT on proliferation in human peripheral blood lymphocytes (PBLs; n = 10), to characterize the binding properties of the NT receptor using Scatchard analysis, and to measure NT receptors using blood volumes (50 ml) applicable to clinical investigation. Incubation of phytohemagglutinin-stimulated PBLs with NT (10^–10 to 10^–13 M) in the presence of 0.07% normal human serum (72 h at 37°C) significantly enhanced proliferation (p < 0.001), which is consistent with PBLs possessing functional NT receptors. However, the various experimental conditions tested constantly yielded low specific NT binding to human PBLs, and hence Scatchard analysis was impossible for 50-ml blood samples. Our data confirm the existence of a link between NT and the immune system and support a physiological significance for this link. However, measurement of NT receptor binding in readily available cells proved unsuitable for clinical investigation.

Functional Characterization of Neurotensin Receptors in Human Cutaneous T Cell Lymphoma Malignant Lymphocytes

“…In this context, several neuropeptides have been reported to modulate the immune responses in the peripheral system (De la Fuente et al, 1998;Delgado et al, 1999) and in the skin (Hosoi et al, 1993;Scholzen et al, 1998). NT is a tridecapeptide ELYENKPRRPYIL, which has been reported to modulate cell functions of both innate and adaptive immunity (Goldman et al, 1982;Koff and Dunegean, 1985;Lemaire, 1988;Garrido et al, 1992;De la Fuente et al, 1993;Evers et al, 1994;Lhiaubet et al, 1998). It was originally isolated from bovine hypothalami (Carraway and Leeman, 1973) and is distributed in the central and peripheral nervous systems and gastrointestinal tract (Carraway and Leeman, 1976;Reinecke, 1985).…”

Neuro-immune modulation of the thymus microenvironment (Review)

“…The neuropeptide NT is known to be involved in the modulation of dopamine signalling in the brain (110). NT has been found to be expressed in human TEC (111) and it has been reported to modulate cell functions of both innate and adaptive immunity (112,113). The prevalent localization of NT on the medullary zone, where the thymus dopaminergic system has been specifically localized (12,66), may support this hypothesis, indicating that NT has a functional role in the thymus medullary environment (90).…”