Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06126 (CD1a)
 2,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inflammatory lesions of the hypophysis include lymphocytic hypophysitis, pituitary abscess, and granulomatous inflammation, with or without specific infections (i.e., sarcoidosis, mycobacteria). These lesions are known to mimic pituitary neoplasms. We report the clinical and pathologic findings in three patients who underwent transsphenoidal resection for presumed pituitary adenoma. Two were women aged 30 years (one with a 5-month history of headache, the other with a 1-year history of menstrual irregularity) and one was a 12-year-old girl with headache, nausea, and diabetes insipidus. Preoperative endocrinologic studies showed increased prolactin in one patient and normal serum thyroid stimulating hormone and prolactin levels in another. By magnetic resonance imaging (MRI), the first case had a 1.2-cm mass with increased signal on T1 and isointensity on T2, ring enhancement after gadolinium, and lateral deviation of the pituitary stalk. The second patient had a 1.1-cm "cystic" mass seen during magnetic resonance imaging with adjacent bony changes seen during computed tomography. In the third, computed tomography showed a hypodense pituitary mass that enlarged during 1-month observation. At surgery, abnormal soft tissue surrounded liquefied material in the anterior pituitary in all cases. Histologic studies showed fragments of intact normal anterior pituitary with preserved vascular and reticulin network and regions of anterior pituitary infiltrated by foamy histiocytes. Other fragments resembled granulation tissue, and some consisted of acellular debris. Histiocytes were immunoreactive for the macrophage marker CD68 and negative for S-100 and CD1a. Ultrastructurally, the normal adenohypophysis was permeated by lipid-laden macrophages. There were no well-formed granulomas or giant cells, hemosiderin, acid-fast bacilli, or fungi. Serial sections and keratin immunostains failed to identify an epithelial cyst lining or keratin among the debris. We propose the term "xanthomatous hypophysitis" for this lesion.
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PMID:Xanthomatous hypophysitis. 963 Jan 81

The natural course and optimal treatment for isolated hypothalamic Langerhans cell histiocytosis (LCH) are unknown. We describe an adult female in whom total resection of a hypothalamic LCH granuloma was performed 12 years after transphenoidal resection of a pituitary adenoma. A retrospective review of the histological specimen of the first operation revealed CD1a positive cells characteristic of LCH along with a plurihormonal adenoma 12 years earlier. No other manifestations of LCH were found and MRI of the brain at the last follow-up 4 years after surgery did not show any recurrent or additional lesion. The diagnosis of isolated hypothalamic LCH is only possible by biopsy and our case demonstrates the feasability of a gross total resection in certain cases.
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PMID:Resection of a Langerhans cell histiocytosis granuloma of the hypothalamus: case report. 1061 92

Folliculo-stellate cells are a nonendocrine, sustentacular-like complementary population of the anterior pituitary. They currently are considered as functionally and phenotypically heterogeneous, with one subpopulation of folliculo-stellate cells possibly representing resident adenohypophyseal macrophages. We took advantage of a limited T-cell mediated inflammatory reaction selectively involving tumor tissue in three cases of pituitary adenoma (2 prolactin cell adenomas, and 1 null cell adenoma) to test the hypothesis whether some folliculo-stellate cells within inflammatory foci would also assume monocytic/dendritic properties. Immunohistochemical double labeling for S-100 protein and the class II major histocompatibility antigen HLA-DR indeed showed several arborized cells to coexpress both epitopes. These were distributed both amidst adenomatous acini and along intratumoral vessels, and were morphologically undistinguishable from conventional folliculo-stellate cells. On the other hand, markers of follicular dendritic cells (CD21) and Langerhans' cells (CD1a) tested negative. Furthermore, no S-100/HLA-DR coexpressing folliculo-stellate cells were seen in either peritumoral parenchyma of the cases in point nor in control pituitary adenomas lacking inflammatory reaction. These findings suggest that a subset of folliculo-stellate cells may be induced by an appropriate local inflammatory microenvironment to assume a dendritic cell-like immunophenotype recognizable by their coexpression of S-100 protein and HLA-DR. By analogy with HLA-DR expressing cells in well-established extrapituitary inflammatory constellations, we speculate that folliculo-stellate cells with such immunophenotype may actually perform professional antigen presentation. A distinctly uncommon finding in pituitary adenomas, lymphocytic infiltrates may therefore be read as a manifestation of tumoral immunosurveillance.
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PMID:Folliculo-stellate cells of "true dendritic" type are involved in the inflammatory microenvironment of tumor immunosurveillance of pituitary adenomas. 1759 15