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)

T-cell prolymphocytic leukemia (T-PLL) is a postthymic T-cell neoplasm with a characteristic morphology and heterogeneous immunophenotype. Most cases of T-PLL express membrane T-cell receptors (TCRs) of the alphabeta phenotype. We experienced a 30-year-old man suffering from TCRgammadelta T-cell leukemia with morphology compatible to T-PLL with a postthymic phenotype. He was admitted with skin eruption and pancytopenia. Peripheral blood and bone marrow were occupied with medium-sized lymphocytes, which had moderately condensed chromatin with a single nucleolus and sparse, nongranular basophilic cytoplasm. The immunophenotype was CD1a-, CD2-, CD3+, CD4-, CD5+, CD7+, CD8-, and terminal deoxynucleotidyl transferase negative. Hepatosplenomegaly was absent. He was diagnosed as having T-PLL and was treated with combination chemotherapy. Six months later the leukemic cell became chemoresistant. Although the patient showed transient improvement in response to pentostatin, he died 13 months after the diagnosis. To our knowledge, this is the first case of T-PLL with a TCRgammadelta phenotype.
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PMID:T-cell receptor gammadelta T-cell leukemia with the morphology of T-cell prolymphocytic leukemia and a postthymic immunophenotype. 1179 17

Interdigitating dendritic cell sarcoma is an extremely rare neoplasm that mainly occurs in the lymph nodes. We report a case of interdigitating dendritic cell sarcoma arising from the spleen, a previously unreported site for interdigitating dendritic cell sarcoma. An 87-year-old woman, visiting Ashigara Hospital with complaints of palpitation and dyspnea, was found to have pancytopenia and low proteinemia. Abdominal ultrasonography and CT scanning demonstrated severe splenomegaly with heterogeneous enhancement. She received a splenectomy under the clinical diagnosis of a splenic tumor. Grossly, the spleen was markedly enlarged, with confluent massive nodules. Microscopically, the normal architecture was effaced with diffuse proliferation of large pleomorphic cells arrayed in a somewhat sheet-like pattern. Erythrophagocytosis was commonly observed. Immunohistochemical studies showed that the tumor cells were positive for S-100 protein, fascin, vimentin, and CD68, but uniformly negative for CD45, B- and T-cell markers, CD1a, CD30, complement receptors, CD34, Factor VIII, HMB-45, and lysozyme. Ultrastructurally, the tumor cells possessed complex interdigitating cytoplasmic dendritic processes. Birbeck granules were absent. Based on these findings, the present case was diagnosed as interdigitating dendritic cell sarcoma. The patient died of multiple liver metastases 3 months postoperatively.
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PMID:Interdigitating dendritic cell sarcoma of the spleen: report of a case with a review of the literature. 1191 34

The molecular mechanisms involved in the pathogenesis of toxic epidermal necrolysis (TEN) remain not fully understood. We report a unique case of antibiotic-induced TEN developed in a patient who also suffered from prolonged severe methotrexate-induced pancytopenia. The objective of the study was to explore the nature of the cutaneous inflammatory infiltrate and the density in dermal dendrocytes (DD). Immunohistochemistry was used to identify activated T lymphocytes (CD45R0), monocyte-macrophages (Mac 387, CD68), DD (Factor XIIIa), and Langerhans cells (CD1a). The proliferation marker (Ki67) and the antibody to Fas receptor (CD95R) were also used to assess the distribution of the germinative pool of keratinocytes and the FAS-related apoptotic process, respectively. Numerous Factor XIIIa+ DD were present in the papillary dermis with only sparce perivascular CD45RO+ T lymphocytes and scattered CD68+ or Mac 387+ macrophages. Double immunostainings revealed that a minority of Factor XIIIa+ DD co-expressed the CD68 glycoprotein (a marker of phagocytic activity). No cells co-expressed factor XIIIa and Mac 387 immunoreactivities. CD45RO+ T lymphocytes, CD68+ and Mac 387+ macrophages were absent in the epidermis. The expression of CD95R was present although restricted to the basal keratinocytes, while the L1-protein (Mac 387+) was diffusely present in the epidermis. Langerhans cells (CD1a+) were sparce, but normal in distribution. The presence of a great number of Factor XIIIa+ DD without any possible recent recruitment from bone marrow suggests that these cells differentiated from resident cells of the skin. Indeed, there was no co-expression of Factor XIIIa and L1-protein, thus showing the absence of recruitment from monocytes. The simultaneous over-expression of Factor XIIIa and CD68 in some DD indicates some phagocytic activity. In view of the absence of inflammatory cells in the epidermis, keratinocytes appeared responsible for their own destruction through CD95-mediated and/or calcium-dependent apoptotic pathways. This finding entails that TEN treatments should target the keratinocyte metabolism rather than the circulating inflammatory cells which presumably play a limited role, if any, in the epidermal destructive process.
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PMID:Drug-induced toxic epidermal necrolysis and pancytopenia: a puzzling association. 1594 74

We report a case of Langerhans' cell histiocytosis (LCH) occurring after a living donor liver transplantation (LDLT) for fulminant hepatitis. A 9-month-old girl underwent an LDLT for fulminant hepatitis of an unknown cause. The histology of the native liver did not show any findings of LCH. On postoperative day 42, her Epstein-Barr virus (EBV)-DNA and cytomegalovirus antigenemia were both found to be positive. As a result, she was treated with antiviral agents and a reduction of the immunosuppression dosage. On postoperative day 98, acute rejection occurred, and she was treated with FK506, methylprednisolone, and finally, anti-CD3 murine monoclonal antibody was added. Subsequently, the EBV was re-activated. Thereafter, skin eruptions, swelling of the systemic lymph nodes, and pancytopenia appeared on postoperative day 127. LCH was diagnosed based on the typical histological findings as LCH, CD1a, and S-100-positive cells in her skin and a lymph nodes biopsy. She was treated by chemotherapy. The symptoms disappeared a few weeks after the start of the chemotherapy, and a clinical remission of LCH was obtained. We could not detect any evidence of EBV infection in the tumor cells. In spite of the fact that her LCH lesions thereafter remained in remission, she died of hepatic failure at 22 months after undergoing the liver transplantation. In conclusion, we discuss the factors influencing the occurrence of LCH in our patient after LDLT, while also evaluating the relationship between LCH and the immunosuppressive therapy administered to this patient.
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PMID:Langerhans' cell histiocytosis after living donor liver transplantation: report of a case. 1623 11

Osteopetrosis (OP) is a clinically and genetically heterogeneous disorder characterized by increased bone density. Associations between OP and other clinical entities are rare but include muscular degeneration, Dandy-Walker syndrome, craniosynostosis, and poikiloderma. Infantile OP has also been diagnosed in a group of infants with neuronal storage disease. An association between OP and juvenile xanthogranuloma (JXG) has never been previously reported. Herein we present a case of an intermediate form of OP in a newborn who presented with hepatosplenomegaly and pancytopenia. Histologic evaluation of a bone marrow biopsy demonstrated abnormally thickened bony trabeculae. A liver biopsy demonstrated prominent expansion of portal areas by a histiocytic infiltrate expressing CD45, CD14, CD68, CD163, factor XIIIa, and fascin, while the biopsy was negative for S100 and CD1a. These findings were those associated with JXG. Genetic testing demonstrated a mutation involving the Pleckstrin homology domain-containing family M member 1 ( PLEKHM1 ) gene. A different mutation in this gene has been previously reported in one other patient with OP. Our case is the 2nd reported case with PLEKHM1 mutation in a patient with a mild form of OP. It also demonstrates the 1st reported occurrence of OP concomitantly with JXG.
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PMID:Infantile osteopetrosis and juvenile xanthogranuloma presenting together in a newborn: a case report and literature review. 2105 59