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PubMed2006

CD4+ memory T cells: functional differentiation and homeostasis.

CD4+ T cells are central regulators of both humoral and cellular immune responses. There are many subsets of CD4+ T cells, the most prominent being T-helper 1 (Th1), Th2, Th-17, and regulatory T cells, specialized in regulating different aspects of immunity. Without participation by these CD4+ T-cell subsets, B cells cannot undergo isotype switching to generate high-affinity antibodies, the microbicidal activity of macrophages is reduced, the efficiency of CD8+ T-cell responses and CD8+ T-cell memory are compromised, and downregulation of effector responses is impaired. It therefore stands to reason that memory CD4+ T cells are likely to fulfill an important facilitator role in the maintenance and control of protective immune responses. This review discusses some issues of importance for the generation of memory CD4+ T cells and focuses in particular on their heterogeneity and plasticity, with respect to both phenotypic characteristics and function. Finally, we discuss a number of factors that affect long-term maintenance of memory CD4+ T cells.

Animals↗
PubMed1989

Structural and functional differentiation of two clinally distributed glucosephosphate isomerase allelic isozymes from the teleost Fundulus heteroclitus.

The teleost Fundulus heteroclitus (L.) possesses two loci, Gpi-A and Gpi-B, for the glycolytic enzyme, glucose-phosphate isomerase (GPI; D-glucose-6-phosphate ketol-isomerase; E.C. 5.3.1.9). The Gpi-B locus is polymorphic in Fundulus, with two common alleles, Gpi-Bb and Gpi-Bc, distributed in a clinal manner in populations along the east coast of North America. Since this clinal distribution is strongly correlated with a temperature gradient, we asked whether the GPI-B2 allozymes were functionally adapted to the thermal environment in which a given phenotype predominated. The two major GPI-B2 allozymes were purified to homogeneity and were characterized as to molecular weight, isoelectric pH, thermal denaturation, and kinetic parameters. Both GPI-Bb2 and GPI-Bc2 allozymes have molecular masses of 110 kD, and they have isoelectric pHs of 6.4 and 6.6, respectively. The GPI-Bb2 allozyme was more stable to thermal denaturation than was the GPI-Bc2 enzyme. Kinetic properties of the allelic isozymes were investigated both as a function of pH and as a function of temperature. At 25 degrees C, over the pH range considered, there were no significant differences between allozymes, either in Km for fructose-6-phosphate or in Ki for 6-phosphogluconate, but apparent Vmax values differed between pH 7.5 and pH 8.5. All steady-state kinetic parameters showed strong temperature dependence, but the allozymes differed only in the Ki for 6-phosphogluconate at temperatures greater than 30 degrees C. On the basis of the observed structural and functional differences alluded to above, the hypothesis that the major allelic isozymes of the Gpi-B locus were functionally equivalent was rejected. However, it is not yet known whether these structural and functional differences have any significance at higher levels of biological organization.

Alleles↗
PubMedDate not supplied

[Functional differentiation of different portions of the the rat neocortex].

The effect of uni- and bilateral ablation of rostral and caudal parts of neocortex on conditioned avoidance reflex was studied on naive and pretrained albino rats. Maximal impairment of the reflex was seen after bilateral ablation of the caudal region of neocortex, minimal one--after unilateral neocortex ablation. The rats without rostral cortex showed medium impairment. After extirpation of caudal cortex the number of positive reactions to light was greater in pretrained rats than in naive ones. After total cortical extirpation the previously elaborated conditioned reflex disappeared irreversibly. The conclusion is made on functional heterogeneity of the rostral and caudal cortex.

Animals↗
PubMed1976

Functional differentiation of the chick endocrine pancreas. II. The alpha cells and glucagon.

A radioimmunoassay for glucagon, together with electron microscopic observations of early embryonic alpha cells were utilized to examine developmental aspects of glucagon accumulation and release in the chick embryo. Immunoreactive glucagon was detected in both the pancreas and blood plasma from the fifth embryonic day onwards. In addition, emiocytotic events were observed in alpha cells as early as the fifth embryonic day. The early appearance of glucagon and its subsequent developmental profile correlate well with major events in carbohydrate metabolism occurring in the embryonic chick, and are discussed in relation to a functionally responding system, the developing liver. The present data show that glucagon is secreted at earlier embryonic stages than hitherto demonstrated, and suggest a developmental role for glucagon in hepatic glycogen metabolism.

Animals↗
PubMed1997

Differential functional effects of a humanized anti-CD4 antibody on resting and activated human T cells.

A fully humanized immunoglobulin G1 (IgG1) anti-CD4 monoclonal antibody is currently being evaluated in phase I/II clinical trials for rheumatoid arthritis. In order to understand the mode of action of this antibody in vivo, we have carried out a detailed functional analysis in vitro of the effects of this antibody on T-cell activation. The anti-CD4 antibody was found to inhibit both antigen-specific responses involving recognition of human leucocyte antigen (HLA) class II and processed antigenic peptides as well as non-class II dependent responses via anti-CD3 antibodies. The antibody did not cause total blockade of T-cell proliferation, but rather induced a shift in the dose-response curve, decreasing the sensitivity of cells to antigen or anti-CD3-mediated stimulation. The antibody appears to allow at least a partial early signal into the T cell as it does not inhibit the increase in tyrosine phosphorylation induced by anti-CD3 antibodies. A comparison of the intact antibody with that of either the F(ab')2 fragment or an engineered non-Fc receptor (FcR) binding form revealed that the intact antibody was the most effective at inhibiting proliferation of resting peripheral blood CD4+ T cells. However, this difference was only apparent when excess antibody was removed from culture prior to antigen or anti-CD3 mediated stimulation. The intact antibody induced both CD4 down-modulation and increases in CD4-associated tyrosine phosphorylation of resting CD4+ T cells, which were not seen with the non-FcR binding versions, which may account for the enhanced potency of the intact antibody at inhibiting T-cell activation. Interestingly, the anti-CD4 antibody induced a differential effect on activated CD4+ T cell clones compared with resting CD4+ T cells with respect to degree of CD4 cross-linking required to induce functional effects in the T cell. Both intact and non-FcR binding antibodies were equally effective at inhibiting T-cell proliferation of activated T-cell clones. In addition CD4 down-modulation and increased CD4-associated tyrosine phosphorylation were observed with T-cell clones in the absence of secondary cross-linking. Such observations may be of relevance when studying the effects of the antibody at sites of inflammation, where there will be CD4+ T cells of differing activation states as well as varying numbers of FcR positive cells.

Antibodies, Monoclonal↗
PubMed1984

Rat liver epithelial cell cultures in a serum-free medium: primary cultures and derived cell lines expressing differentiated functions.

Rat liver epithelial cells explanted in a serum-free medium (SFM) composed of Ham's F10 basal medium plus free fatty acids adsorbed on bovine albumin gave successful rise to primary cultures and then to long-term cell lines that expressed liver functions; induction of L-tyrosine aminotransferase by glucocorticoids, hepatic pattern of progesterone metabolism, and biosynthesis of murine primary bile acids; chenodeoxycholic and cholic acid common to higher vertebrates and alpha-muricholic acid specific of the rat bile.

Animals↗
PubMed1993

Differential function of the costal and crural diaphragm during emesis in canines.

In six mongrel dogs under thiopental anesthesia, piezoelectric transducers and bipolar electromyographic (EMG) wires were installed onto left costal, medial crural and lateral crural segments of the diaphragm. During CO2 rebreathing, shortening and EMG activity increased significantly in all three regions of the diaphragm compared to resting breathing. During emesis, (1) both shortening and EMG activity significantly increased compared to resting in costal segment; however, (2) lateral crural shortening was not increased in spite of significant increase in EMG activity; furthermore, (3) the medial crural segment lengthened without any increased EMG activity. These results demonstrate a differential recruitment of costal and crural diaphragm segments, and an additional differential activity within the crural segment between medial and lateral crural regions, during emesis. This activity of the canine diaphragm is consistent with a central influence of emesis upon individual regions of the diaphragm.

Animals↗
PubMed1993

Acetylcholinesterase staining differentiates functionally distinct auditory pathways in the barn owl.

The aim of this study was to examine how the functional specialization of the barn owl's auditory brainstem might correlate with histochemical compartmentalization. The barn owl uses interaural intensity and time differences to encode, respectively, the vertical and azimuthal positions of sound sources in space. These two auditory cues are processed in parallel ascending pathways that separate from each other at the level of the cochlear nuclei. Sections through the auditory brainstem were stained for acetylcholinesterase (AChE) to examine whether nuclei that process different auditory cues stain differentially for this enzyme. Of the two cochlear nuclei, angularis showed more intense staining than nucleus magnocellularis. Nucleus angularis projects to all of the nuclei and subdivisions of nuclei that belong to the intensity processing pathway. Acetylcholinesterase stained all regions that contain terminal fields of nucleus angularis and thus provided discrimination between the time and intensity pathways. Moreover, staining patterns with acetylcholinesterase were complementary to those previously reported with an anti-calbindin antibody, which stains terminal fields of nucleus laminaris, and thus stains all the nuclei and subdivisions of nuclei that belong to the time pathway. Some of the gross staining patterns observed with AChE were similar to those reported with antibodies to glutamate decarboxylase. However, AChE is a more convenient and definitive marker in discriminating between these pathways than is calbindin or glutamate decarboxylase. Acetylcholinesterase staining of the intensity pathway in the owl may be related to encoding of sound intensity by spike rate over large dynamic ranges.

Acetylcholinesterase↗
PubMed1995

Stimulation of rat granulosa cell progesterone production but not other differentiated functions by a splenocyte-derived factor.

Concanavalin A-stimulated splenocytes secrete a factor that stimulates progesterone production in cultured rat granulosa cells. The actions of this progesterone-stimulating factor (PSF) were characterized further by purifying it by sequential chromatographies on heparin-agarose, copper chelating-Sepharose and Mono S columns. Several of its effects on granulosa cells were then compared with those of FSH. Like FSH, PSF induced accumulation of progesterone and 20 alpha-dihydroprogesterone in granulosa cell culture media; however, the time course of progesterone accumulation in response to PSF was much slower than that in response to FSH. In contrast to FSH, PSF induced little accumulation of oestrogen. Induction of other differentiated responses was compared by pretreating cultured granulosa cells with either FSH or PSF, and then challenging with LH, prolactin, epidermal growth factor or the beta-adrenergic agonist, isoproterenol. Pretreatment with FSH induced subsequent responsiveness to all four agents, whereas pretreatment with PSF induced subsequent responsiveness only to isoproterenol. These results indicate that granulosa cell responses to PSF are much more limited than are those to FSH and that these responses are characterized by an increase in progestin production.

Animals↗
PubMedDate not supplied

[Functional differentiation of the tail muscle fibers in Rana temporaria tadpoles].

Studies have been made on changes in the electrical properties of muscle membrane and lipid content of two types of myotomal fibers in the tail of tadpoles during metamorphosis. It was shown that during premetamorphosis, peripheral and inner muscle fibers do not differ with respect to their effective resistance, time constant of the membrane and lipid content; the resting membrane potential is higher in the inner fibers. During further development of the tadpoles, differentiation of muscle fibers takes place, and to the beginning of the climax the inner fibers attain lower values of the effective resistance and time constant, as well as lower content of lipids in their sarcoplasm; the difference in the level of resting membrane potential between the peripheral and inner fibers increases. The data obtained suggest that the inner fibers may be referred to as fast ones, whereas the peripheral ones--as slow. These data also reveal specific features in neurotrophic regulation of functional properties of muscle fibers in tadpoles.

Animals↗
PubMed2026

Distinct cell morphotypes of Aureobasidium melanogenum ZN exhibit differential functional profiles in promoting maize growth.

Black yeast-like fungi of the genus Aureobasidium exhibit morphological plasticity, but whether distinct cellular states within the same genetic background are associated with different plant growth-promoting functions remains unclear. Here, yeast-like cells (YL), swollen cells (SC), and chlamydospores (CH) of Aureobasidium melanogenum ZN were characterized. YL was associated mainly with siderophore production and laccase activity, SC with extracellular polysaccharide accumulation, and CH with phosphate mobilization and higher ammonia and IAA production. Whole-genome and comparative genomic analyses revealed a shared repertoire related to nutrient acquisition, auxin-associated metabolism, extracellular oxidation, and carbohydrate remodeling, with expansions in nutrient- and cell-surface-related gene families. Transcriptomic and metabolomic analyses showed distinct deployment of these capacities, with CH exhibiting broad reprogramming of tryptophan-associated, nitrogen, phosphate, central-carbon, and amino-acid metabolism. In maize, CH at the optimal inoculation concentration of 105 CFU·mL-1 produced the strongest growth promotion, increasing plant height, dry biomass, root length, root surface area, and root volume by 58.6%, 365.1%, 191.0%, 194.3%, and 222.4%, respectively. Consistent with this pronounced growth phenotype, maize root transcriptomics showed coordinated CH-induced responses involving root development, nutrient transport, redox regulation, and root-interface remodeling. Root-zone tracking showed greater short-term stability and persistence of CH. These findings identify cellular state as an important functional dimension of Aureobasidium-plant interactions and provide a basis for developing fungal inoculants with defined beneficial cellular states.

Zea mays↗
PubMed1976

Differential function of major histocompatibility complex antigens in T-lymphocyte activation.

We have emphasised the functional dichotomy of MHC LD and LD antigens as well as the differences in cellular responses to these antigens. Perhaps in so doing we have failed to stress adequately the similarities that exist. But while the similarities (for example skin graft rejection associated with both K and I region differences) are so very clear, the differences have best allowed our progressive understanding of MHC induced cellular responses from the perspective stressed in this article. Of greatest importance to our understanding of these transplantation antigens are the potentially differential roles for the LD and SD antigens in the complex series of events that are collectively referred to as the "allograft reaction". It has been suggested that these differences may be "merely quantitative". This possibility has been discussed repeatedly in our previous reports on the distinction of LD and SD. In fact, the great bulk of biological phenomena can be reduced to quantitative differences. It would seem to us that sufficient evidence for such differential activity exists to make the LD-SD dichotomy model an heuristically valuable one for purposes of designing future experiments. We have discussed the clinical relevance of this model elsewhere. Many authors have speculated and evidence has been gathered to suggest, that cell surface antigens associated with the MHC are important in developmental and other cell interactions. Some studies have directly addressed the question of the need for MHC compatibility to allow cell interaction to proceed optimally. It thus seems most appropriate that the genetic complex with which we are dealing has been termed the major histocompatibility complex; allowing for the literal interpretation of this term this may be the genetic region that by its influence on "tissue compatibility" may control critical cellular interactions in addition to those observed in allograft reactions. It is the simple good fortune for those whose attention was focused on this complex by transplantation problems to find themselves with a panorama of biological phenomena that require extensive experimental probing and integration, hopefully ultimately leading to an understanding of the MHC in a broader context than has to date been possible.

Animals↗
PubMed1975

Functional differentiation of splanchnic A delta fibres in relation to viscerosomatic reflexes.

The splanchnic afferent signal in the myelinated fibre spectrum was analysed in cats and its relationship to viscerosomatic reflex activity was studied. In addition to Abeta and Adelta components, a further elevation was observed in the sympathetic chain neurogram. According to the conduction rate (15 plus or minus 4 m/sec), it was caused by myelinated fibres 2-3 mu in diameter. The presence of this component at thoracic dorsal root level, or in the sympathetic chain in stimulation of the postganglionic part of the nerve trunk, confirmed the afferent nature of the observed activity. The threshold stimulus for these fibres, which were termed group Adelta2, was four times higher than for Abeta fibres. Correlation of the neurogram with evoked activity in the intercostal nerves confirmed the different functional role of group Adelta2 fibres. Adelta2 fibre activity evokes the early component of the two-component viscerosomatic discharge and Adelta2 fibre activity its later component. The authors discuss the functional significance of Adelta2 fibres, which probably mediate nociceptive information from the viscera.

Animals↗
PubMed2002

Differential functions of IL-4 receptor types I and II for dendritic cell maturation and IL-12 production and their dependency on GM-CSF.

Little is known about the distinct roles of the two types of IL-4R on DC. Here we report that IL-4 and IL-13 are able to promote DC maturation, as evaluated by up-regulation of MHC class II and costimulatory molecules, when the concentration of GM-CSF is relatively lower than the dose of IL-4 or IL-13. In addition, under these conditions both cytokines enable DC to respond to maturation stimuli such as bacterial products or proinflammatory cytokines. Both IL-4 and IL-13 act synergistically with weak maturation stimuli such as TNF-alpha or CD40. The IL-4R signaling for DC maturation requires the IL-4R alpha-chain and STAT6, but not Janus kinase 3, indicating that IL-4R type II signaling is preferentially responsible for these effects. In contrast, the production of IL-12 p70, but not IL-10 and TNF, induced by microbial products was enhanced only by IL-4, not by IL-13 or Y119D, a selective type II IL-4R agonist, in vitro and in vivo. This enhancement was dependent on the presence of Janus kinase 3, indicating that this function is exclusively mediated by the type I IL-4R. In short, we discerned the individual roles of the two IL-4R types on DC function, showing that IL-4R type I promotes IL-12 secretion independently of GM-CSF concentration, while IL-4R type II promotes the up-regulation of MHC class II and costimulatory surface markers in a GM-CSF concentration-dependent manner.

Animals↗
PubMed2005

Structural and functional differentiation of three groups of tyrosine residues by acetylation of N-acetylimidazole in manganese stabilizing protein.

To study its contribution to the assembly of the green plant manganese stabilizing protein (MSP) into photosystem II (PSII), tyrosine residues were specifically acetylated using N-acetylimidazole (NAI). In soluble MSP, three groups of Tyr residues could be differentiated by NAI acetylation: approximately 5 (actually approximately 5.2) Tyr residues could be easily acetylated (superficial), 1-2 Tyr residues could be acetylated when the NAI concentration was sufficiently high (superficially buried), and 1-2 Tyr residues could only be acetylated in the presence of the denaturant, urea (deeply buried). Acetylation of the 5.2 Tyr residues did not affect the reconstitution or oxygen-evolving activities of the MSP, and far-UV circular dichroism (CD) analysis showed that the altered MSP retained most of its native secondary structure. These results suggested that the 5.2 Tyr residues are not absolutely essential to the function of MSP. However, further modification of the 1-2 superficially buried Tyr residues (for a total acetylation of approximately 6.4 Tyr residues) completely abrogated the MSP rebinding and oxygen evolution activities. Finally, at least one tyrosine residue was inaccessible to NAI until MSP was completely unfolded by 8 M urea. Deacetylation of MSP with 6.4 or 8 acetylated Tyr residues with hydroxylamine restored most of the rebinding and oxygen-evolving activities. A prominent red shift in fluorescence spectra of MSP (excited at 280 or 295 nm) was observed after modification of 6.4 Tyr residues, and a further shift could be found after all 8 Tyr residues were modified, indicating a great loss of native secondary structure. Far-UV CD revealed that MSP was mostly unfolded when 6.4 Tyr residues were modified and completely unfolded when all 8 Tyr residues were modified. Fluorescence and far-UV CD studies revealed that loss of MSP rebinding to PSII membranes following NAI modification correlated well with conformational changes in MSP. Together, these results indicate that different tyrosine residues have different contributions to the binding and assembly of MSP into PSII.

Acetylation↗
PubMed1999

IL-15 promotes survival but not effector function differentiation of CD8+ TCRalphabeta+ intestinal intraepithelial lymphocytes.

CD8 single-positive cells, including CD8alphaalpha+ and CD8alphabeta+ subsets, constitute the majority of TCRalphabeta+ intestinal intraepithelial lymphocytes (alphabeta iIEL) in mice. CD8+ alphabeta iIEL show significantly weaker responses to TCR stimulation in the presence of exogenous IL-2 than do CD8+ T cells of the central immune system. IL-15 is a T cell growth factor likely expressed in the intestine mucosa. To understand the role of IL-15 in CD8+ alphabeta iIEL biology, we compared the effects of exogenous IL-15 and IL-2 on the survival and primary responses of the two CD8+ alphabeta iIEL subsets in vitro. In contrast to the death of approximately 60% of both CD8alphaalpha+ and CD8alphabeta+ iIEL cultured in IL-2 with or without TCR stimulation, IL-15 promoted survival of the CD8alphaalpha+ subset in the presence of TCR stimulation and promoted survival of both subsets in the absence of TCR stimulation. The higher proliferation level of TCR stimulated CD8alphaalpha+ alphabeta iIEL cultured in IL-15 compared with those cultured in IL-2 is likely due to IL-15's prosurvival effects. In addition, unlike exogenous IL-2, exogenous IL-15 did not support the effector functions of either iIEL subsets, including IFN-gamma production, IL-4-induced Th2 cytokine production, and anti-TCR mAb-redirected cytotoxicity. These findings demonstrate that IL-15 and IL-2 are functionally distinct and suggest that IL-15 plays a unique role in the maintenance of the CD8+ alphabeta iIEL pool in the absence of Ag stimulation and in the survival and expansion of CD8alphaalpha+ alphabeta iIEL upon Ag stimulation.

Animals↗
PubMedDate not supplied

[Functional differentiation of thymocytes induced by macrophages: cellular, humoral and genetic aspects].

The cellular, humoral and genetical mechanisms of induction of T-effectors of the graft vs. host reaction (GHR) were studied in a double-cell culture of phagocytizing mononuclears with thymocytes. Experiments were carried out on mice of inbred and recombinant strains. The GHR intensity was estimated by the increase in the number of cells in the popliteal lymph node, regional with reference to the introduction of parental thymocytes into the F1 hybrid. For the induction of the GHR T-effectors from the immature population of thymocytes to be realized, a direct physical contact and identity by the H-2K locus of the major histocompatibility complex between the cooperating cells in culture are indispensable. An antiserum containing antibodies against the H-2K locus products prevents the induction. At the same time antibodies against antigens controlled by loci of I-region or the H-2D locus do not affect the accumulation of T-effectors. Contact interaction of phagocytizing mononuclears with thymocytes results in accumulation of a 65,000 D humoral factor in the culture medium. Incubation of the intact thymocytes with this factor ensures functional transformation of immature thymocytes to corresponding effector cells. For the humoral induction of T-effectors to be successfully realized, identity by the T-2K locus between the factor producents and intact thymocytes is indispensable, as well as in the conditions of direct intercellular interaction. It is suggested that H-2K specificity is incorporated into the factor structure.

Animals↗
PubMed1998

Ependymal and choroidal cells in culture: characterization and functional differentiation.

During the past 10 years, our teams developed long-term primary cultures of ependymal cells derived from ventricular walls of telencephalon and hypothalamus or choroidal cells (modified ependymal cells) derived from plexuses dissected out of fetal or newborn mouse or rat brains. Cultures were established in serum-supplemented or chemically defined media after seeding on serum-, fibronectin-, or collagen-laminin-coated plastic dishes or semipermeable inserts. To identify and characterize cell types growing in our cultures, we used morphological features provided by phase contrast, scanning, and transmission electron microscopy. We used antibodies against intermediate filament proteins (vimentin, glial fibrillary acidic protein, cytokeratin, desmin, neurofilament proteins), actin, myosin, ciliary rootlets, laminin, and fibronectin in single or double immunostaining, and monoclonal antibodies against epitopes of ependymal or endothelial cells, to recognize ventricular wall cell types with immunological criteria. Ciliated or nonciliated ependymal cells in telencephalic cultures, tanycytes and ciliated and nonciliated ependymal cells in hypothalamic cultures always exceeded 75% of the cultured cells under the conditions used. These cells were characterized by their cell shape and epithelial organization, by their apical differentiations observed by scanning and transmission electron microscopy, and by specific markers (e.g., glial fibrillary acidic protein, ciliary rootlet proteins, DARPP 32) detected by immunofluorescence. All these cultured ependymal cell types remarkably resembled in vivo ependymocytes in terms of molecular markers and ultrastructural features. Choroidal cells were also maintained for several weeks in culture, and abundantly expressed markers were detected in both choroidal tissue and culture (Na+-K+-dependent ATPase, DARPP 32, G proteins, ANP receptors). In this review, the culture models we developed (defined in terms of biological material, media, substrates, duration, and subculturing) are also compared with those developed by other investigators during the last 10 years. Focusing on morphological and functional approaches, we have shown that these culture models were suitable to investigate and provide new insights on (1) the gap junctional communication of ependymal, choroidal, and astroglial cells in long-term primary cultures by freeze-fracture or dye transfer of Lucifer Yellow CH after intracellular microinjection; (2) some ionic channels; (3) the hormone receptors to tri-iodothyronine or atrial natriuretic peptides; (4) the regulatory effect of tri-iodothyronine on glutamine synthetase expression; (5) the endocytosis and transcytosis of proteins; and (6) the morphogenetic effects of galactosyl-ceramide. We also discuss new insights provided by recent results reported on in vitro ependymal and choroidal expressions of neuropeptide-processing enzymes and neurosecretory proteins or choroidal expression of transferrin regulated through serotoninergic activation.

Animals↗