Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interactions between human recombinant H- and L-ferritins and human lymphocytes were studied in vitro by direct binding assays and by flow cytometry. L-ferritin did not cause detectable specific binding, whereas H-ferritin showed a specific and saturable binding that increased markedly in phytohemagglutinin (PHA)-stimulated cells. This ferritin bound up to 30% of CD4+ and CD8+ T-lymphocytes and most B cells, indicating that expression of ferritin binding sites is not related to cell lineage or function. Dual-color flow cytometry experiments showed that ferritin binding sites were present on cells expressing the proliferation markers HLA-DR, MLR3, interleukin 2 (IL-2), and transferrin receptors (Tf-R). In addition, after PHA induction, the time course of the expression of H-ferritin binding sites was similar to those of the above proliferation markers. Ferritin binding sites were observed in lymphocytes at all cell cycle phases, including the early S-phase. H-Ferritin at nanomolar and picomolar concentrations had an inhibitory effect on PHA-induced blastogenesis. We propose that H-ferritin binding sites behave like proliferation markers, with the unusual function of downregulating proliferation.
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PMID:Specific binding sites for H-ferritin on human lymphocytes: modulation during cellular proliferation and potential implication in cell growth control. 183 Oct 58

A strong immunoreactivity for ferritin was observed in the neuritic (senile) plaques in Alzheimer's disease hippocampus. The ferritin accumulation was almost exclusively associated with the microglia, which appeared to have proliferated greatly. These cells were also positive for HLA-DR, a putative marker for reactive microglia. In contrast, in the diffuse plaques, which were without neuritic pathology, the ferritin-stained microglia appeared to be normal. Microglia were seen frequently in contact with neurons undergoing neurofibrillary changes but only the tangles in the extracellular space were ferritin positive. No ferritin was detected, by Western blots, in paired helical filaments isolated from Alzheimer's disease brain, suggesting that ferritin was most likely weakly associated with and was not a constituent of these fibrils. No correlation between increased ferritin/microglia activity and blood-brain barrier leakage was detected. Ferritin, an iron-storage protein, might have a role in the formation of amyloid through the action of free radicals generated during the release of iron from the ferritin molecule. Alternatively, the ferritin/microglia system might be secondarily involved in the removal and processing of the amyloid.
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PMID:Ferritin is a component of the neuritic (senile) plaque in Alzheimer dementia. 208 50

Ultrastructural, enzyme histochemical and immunohistochemical studies were performed on tissue obtained from eight cases of malignant fibrous histiocytoma (MFH) and five cases of sacral decubitus ulcer. The MFH was composed of two major tumour cell types: fibroblast-like and histiocyte-like cells. Both cell types demonstrated abundant branching, fragmented rough endoplasmic reticulum (rER), many free ribosomes, occasional small mitochondria, an oval, elliptical or irregularly shaped nucleus with one or two prominent nucleoli and often a few dense bodies. However, pseudopodial projections, multivesicular bodies and phagosomes, common histiocyte organelles, were not seen. With little difference between cases or selection sites, the MFH cells reacted to acid phosphatase (AcP) and alpha-naphtyl butyrate esterase (ANBE) by enzyme histochemistry and with ferritin (Fer), alpha 1-antitrypsin (AT), alpha 1-antichymotrypsin (ACT), fibronectin (FN), HLA-DR, HLA-DP, Leu 10 and OKT 9 in immunohistochemical studies. MFH tumour cells did not immunostain with monocyte/macrophage markers (Leu M1, Leu M3, Mo 1, Mo 2 and Macrophage) although non-neoplastic histiocytes did react to these markers. In addition, granulation tissue, such as that found in sacral decubitus ulcers, was examined and the existence of a specific cell type called the "fibrohistiocytoid (FH) cell" was documented. The FH cell was short, spindle shaped and elliptical. Ultrastructurally, it had fragmented rER distributed in a branching pattern, dispersed free ribosomes, small mitochondria and a few dense bodies, but lacked diverse fused lysosomes and distinct pseudopodial cytoplasmic extensions. The FH cells reacted with AcP, alkaline phosphatase and ANBE but not with peroxidase using enzyme histochemistry and with Fer, AT, ACT, FN, HLA-DR, HLA-DP, Leu 10 and OKT 9 but not with monocyte/macrophage markers, C3d receptor, C3bi receptor in immunohistochemical studies. The FH cells had morphological, enzyme histochemical and immunohistochemical characteristics intermediate between fibroblasts and histiocytes. Similarities between MFH cells and the FH cells seen in chronic inflammation are discussed.
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PMID:Malignant fibrous histiocytoma: similarities to the "fibrohistiocytoid cells" in chronic inflammation. 254 May 88

Resting human T-lymphocytes show an elevated intracellular concentration of ferritin, whereas transferrin receptors are not detectable. Stimulation by phytohemagglutinin markedly lowers their ferritin content, while inducing the synthesis of transferrin receptors. Addition of iron salts (ferric ammonium citrate) in activated T-lymphocyte cultures causes a marked enhancement of both [3H]uridine and [3H]thymidine incorporation. Nevertheless, it also induces a concentration-dependent decrease in transferrin receptor synthesis, associated with a marked rise of ferritin production. Hemin treatment exerts the same effects. Addition of picolinic acid in phytohemagglutinin-stimulated cultures causes a decrease of [3H]thymidine incorporation, whereas transferrin expression is markedly enhanced. The action of iron salts and chelators is specific for transferrin receptors, since the expression of other membrane markers of activated human T-lymphocytes (interleukin-2 receptor, insulin receptor, and HLA-DR antigen) is not modified by treatment with iron or picolinic acid. These observations suggest that expression of transferrin receptors in activated T-lymphocytes is specifically modulated by their intracellular iron level, rather than their proliferative rate. Addition of picolinic acid to resting T-lymphocytes in the absence of mitogen induces a marked decrease of their ferritin content, but not the appearance of transferrin receptors. On the basis of these results, we suggest a three-step model: (a) in resting T-lymphocytes, the gene for transferrin receptor is apparently "closed," in that it is not expressed under both normal conditions and following iron deprivation. (b) After mitogen stimulus, T-lymphocytes are reprogrammed into cell cycle progression, which necessarily entails synthesis of transferrin receptors (c) Expression of these receptors is modulated by the intracellular iron level, rather than the rate of proliferation per se.
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PMID:Expression of transferrin receptors in phytohemagglutinin-stimulated human T-lymphocytes. Evidence for a three-step model. 300 77

1. Measurements of T-lymphocyte surface ferritin using flow cytometry show that phytohaemagglutinin (PHA) stimulation causes a marked increase in the number of cells bearing spleen-type (S) and heart-type (H) ferritin on their membrane, whereas no such change occurs in non-stimulated cells. This coincides with increases in interleukin-2 receptors, transferrin receptors and HLA-DR antigen. 2. There is an increase in the intracellular concentration of both S- and H-ferritin in lymphocytes after PHA stimulation: H-ferritin increases five- to seven-fold, but S-ferritin only two-to three-fold. The maximum H/S ratio is about 15/1. However, these increases also occur in cells cultured in the absence of PHA. 3. Small amounts of both S- and H-ferritin are released into the medium, especially from stimulated cells, but the H/S ratios are lower than intracellular ratios. 4. The present findings suggest that lymphocyte stimulation followed by ferritin synthesis is accompanied by an increase in the amount of intracellular and cell surface ferritin and, possibly, the amount released from the cells.
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PMID:The response of intracellular and surface ferritin after T-cell stimulation in vitro. 350 Aug 21

Cancer grows in interaction with the host, that is, a host-tumor relationship exists. Investigations of host factors in patients receiving cancer chemotherapy are important, as they reveal the conditions in which a tumor response can develop. Furthermore, reliable host factors, if present, will be useful for quantitative evaluation of the effects of treatment. We have investigated the following three categories of host factors in relation to the effects of cancer chemotherapy and/or immunotherapy. CBC, and blood chemistries (44 parameters). Tumor markers; sialic acid, RNase, lysozyme, ferritin, IAP (immunosuppressive acidic protein), elastase I, AFP, CEA, POA, CA 19-9, CA 125, etc. Immunological parameters; lymphocyte, active T cell, T cell, B cell, IgG Fc receptor-positive T cell, lymphocyte blastogenesis stimulated by PHA, or concanavalin-A, ADCC activity, interferon production in vitro induced by poly I: C, or PHA, PPD skin test, immune complex, immunoglobulin G, A, and M, OKT series 3, 4, 8, 11, 4/8 ratio, antihuman HLA-DR, Leu 11, NK cell activity, etc. From our clinical observations, there were no significant differences in the pretreatment levels of these parameters between responders and non-responders. In responders, there was a tendency for the host factors to show greater degrees of improvement following treatment than in non-responders, but none proved to be reasonably reliable parameters for evaluating therapeutic effects. On the other hand, from our clinical observations on the advanced gastric cancer cases, life span showed a close correlation with tumor regression induced by cancer chemotherapy. Because of these facts, it is only natural that the clinical effects of chemotherapy are currently determined by definite tumor regression.
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PMID:[Host factors in cancer chemotherapy]. 372 33

To search for lymphocyte marker antigens on the surface of human T-cell leukemia virus (HTLV), an immunoelectron microscopic study was performed on a HTLV-producing human T-cell line, MT-2, using monoclonal antibodies, such as anti-Leu-1, -Leu-2b, -Leu-3a, -Leu-5, -Leu-10 and -HLA-DR and OKIal. The reactivity of each antibody with MT-2 cells was tested by the immunoperoxidase method at the light microscopic level. OKIal, anti-HLA-DR and -Leu-10 gave positive results. At the ultrastructural level, the surface of HTLV as well as the plasma membranes of MT-2 cells were labeled with ferritin by the monoclonal antibodies OKIal, anti-HLA-DR and -Leu-10, but not by anti-Leu-1 and -Leu-3a. These findings suggest that HLA-D region -associated antigens are common antigenic determinants shared by the surface of HTLV and the plasma membranes of MT-2 cells. These antigens on the virus surface are probably picked up selectively from the plasma membranes and may play an important role in the interaction of HTLV and target T-cells.
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PMID:Detection of HLA-D-region-associated antigens on the surface of adult T-cell leukemia virus particles by immunoelectron microscopy. 609 44

A case of peripheral T-cell lymphoma classified, according to the updated Kiel classification, as a large pleomorphic T-cell lymphoma with a high content of reactive histiocytes and blood hypereosinophilia is reported. Light microscopic examination revealed a diffuse effacement of the lymph node structure by large pleomorphic lymphoma cells mixed with eosinophils and many histiocytes, some of them presenting discrete features of hemophagocytosis. The neoplastic cells were CD3, CD5, CD8 and HLA-DR positive but failed to show CD30 antigen. DNA molecular analysis displayed simultaneous rearrangements of the genes coding for the delta chain of the T-cell receptor and for the Ig heavy chain. Increased serum levels of angiotensin converting enzyme and ferritin were found and probably induced by the reactive histiocytes. Immunoassays (ELISA) with antibodies directed against some cytokines and against the Tac peptide (sIL-2R) were performed. They demonstrated high serum levels of sIL-2R and a slight increase in GM-CSF, but neither IL-5 nor IL-3. The association of blood hypereosinophilia and histiocytic hyperplasia with a peripheral T-cell lymphoma is discussed.
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PMID:A case of pleomorphic T-cell lymphoma with a high content of reactive histiocytes presented with hypereosinophilia. 747 65

Microwave antigen retrieval methods were assessed for a panel of antibodies on formalin-fixed, paraffin-embedded sections from a range of human central nervous system (CNS) tissues taken at post-mortem. The immunoreactivity of a number of antigens (synaptophysin, PGP9.5, GFAP, carbonic anhydrase II, CD68, ferritin, HLA-DR, alpha beta-crystallin, measles and herpes viruses) was markedly enhanced by this procedure compared with other methods of antigen unmasking, such as trypsinization. Enhancement was noted both by an increased number of positive cells and by the intensity of reactions within individual cells and their processes. Furthermore, the microwave method produced uniform immunostaining over large surface area sections with no loss of morphological detail. Large cryostat sections of CNS tissue can be difficult to obtain with good morphology. The ability to retrieve a wide range of antigen in formalin-fixed, paraffin-embedded CNS tissue will greatly increase the range of investigations that can be carried out on this type of stored material.
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PMID:Microwave antigen retrieval for immunocytochemistry on formalin-fixed, paraffin-embedded post-mortem CNS tissue. 895 20

A fifty five-year-old male presenting as FAB M6 had blasts that were positive both for erythroblastic and megakaryocytic surface makers, i.e., carbonic anhydrase I, CD36 and CD41. HLA-DR and cD71 were also positive. In a very small portion, CD33 and glycophorin A were also positive. By Giemsa staining, these blasts were relatively large and had basophilic cytoplasm. By electroscopic study, PPO was negative and showed ferritin particles, theta granules and iron containing mitochondria in cytoplasm. Chromosome analysis revealed major karyotypic abnormality (MAKA). After initial treatment with blood transfusion, prednisolone and exymetholone, CD41b increased in positive ratio. Trial of remission induction with BHAC-DMP failed and patient died in 5 months.
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PMID:[Acute erythroblastic leukemia presenting as FAB M6 with surface marker positive for megakaryocytic and erythroid: report of a case]. 813 10


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