Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0032463 (
polycythemia vera
)
3,374
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The aberrant overexpression of interleukin 6 (IL-6) is implicated as an autocrine mechanism in the enhanced proliferation of the neoplastic cell elements in various B- and T-cell malignancies and in some carcinomas and sarcomas; many of these neoplasms have been shown to be associated with a mutated p53 gene. The possibility that wild-type (wt) p53, a nuclear tumor-suppressor protein, but not its transforming mutants might serve to repress IL-6 gene expression was investigated in HeLa cells. We transiently cotransfected these cells with constitutive cytomegalovirus (CMV) enhancer/promoter expression plasmids overproducing wt or mutant human or murine p53 and with appropriate chloramphenicol acetyltransferase (CAT) reporter plasmids containing the promoter elements of human IL-6, c-fos, or beta-actin genes or of porcine
major histocompatibility complex
(
MHC
) class I gene in pN-38 to evaluate the effect of the various p53 species on these promoters. Murine and human wt p53 derived from pCMVNc9 and pC53-SN3, respectively, strongly repressed the IL-6 (promoter position -225 to +13), c-fos (-711 to +42), beta-actin (-3400 to +912), and
MHC
(-528 to -38) promoters in serum-induced HeLa cells; additionally, IL-6 promoter/CAT transcription unit constructs induced by IL-1, phorbol ester, or pseudorabies virus were also repressed by wt human and murine p53. The murine transforming mutant p53 (pCMVc5) was less active in repressing the IL-6, c-fos, beta-actin, and
MHC
promoter constructs. The human p53 mutant derived from pC53-SCX3 was also less active than the wt protein in repressing the IL-6, c-fos, beta-actin, and
MHC
promoters, except that serum-induced IL-6/CAT expression was equally repressed by both human wt and mutant p53. In similar transient transfection experiments in HeLa cells, overexpression of the wt human retinoblastoma susceptibility gene product, RB, was found to repress the serum-induced IL-6 (-225 to +13), c-fos (-711 to +42), and beta-actin (-3400 to +912) promoters but not the
PRV
-induced IL-6 (-110 to +13) or the serum-induced
MHC
(-528 to -38) promoters. These observations identify transcriptional repression as a property of p53 and suggest that p53 and RB may be involved as transcriptional repressors in modulating IL-6 gene expression during cellular differentiation and oncogenesis.
...
PMID:Repression of the interleukin 6 gene promoter by p53 and the retinoblastoma susceptibility gene product. 165 55
Pseudorabies virus (
PRV
; suid herpesvirus 1) infection causes heavy economic losses in the pig industry. Therefore, vaccination with live attenuated viruses is practiced in many countries. This vaccination was demonstrated to induce extrathymic virus-specific memory CD4+CD8+ T lymphocytes. Due to their
major histocompatibility complex
(
MHC
) class II-restricted proliferation, it is generally believed that these T lymphocytes function as memory T-helper cells. To directly prove this hypothesis, 15-amino-acid, overlapping peptides of the viral glycoprotein gC were used for screening in proliferation assays with peripheral blood mononuclear cells of vaccinated d/d haplotype inbred pigs. In these experiments, two naturally processed T-cell epitopes (T1 and T2) which are MHC class II restricted were identified. It was shown that extrathymic CD4+CD8+ T cells are the T-lymphocyte subpopulation that responds to epitope T2. In addition, we were able to show that cytokine secretion can be induced in these T cells through recall with inactivated
PRV
and demonstrated that activated
PRV
-primed CD4+CD8+ T cells are able to induce
PRV
-specific immunoglobulin synthesis by
PRV
-primed, resting B cells. Taken together, these results demonstrate that the glycoprotein gC takes part in the priming of humoral anti-
PRV
memory responses. The experiments identified the first T-cell epitopes so far known to induce the generation of virus-specific CD4+CD8+ memory T lymphocytes and showed that CD4+CD8+ T cells are memory T-helper cells. Therefore, this study describes the generation of virus-specific CD4+CD8+ T cells, which is observed during vaccination, as a part of the potent humoral anti-
PRV
memory response induced by the vaccine.
...
PMID:Vaccine-induced, pseudorabies virus-specific, extrathymic CD4+CD8+ memory T-helper cells in swine. 957 53