Human T cells that have been conditioned by the proteolytic activity of the major dust mite allergen Der p 1 trigger enhanced immunoglobulin E synthesis by B cells

BACKGROUND: We have previously demonstrated that the proteolytic activity of Der p 1 selectively cleaves human CD25, the 55 kDa alpha subunit of the IL-2 receptor. As a result of cleavage of surface CD25, peripheral blood T cells produce less IFN-gamma and more IL-4, thereby leading to progressive polarization of the T cells towards a Th2 cytokine profile. Therefore, these observations underline the potential role of the proteolytic activity of Der p 1 in creating a microenvironment conducive for IgE synthesis. OBJECTIVE: To study the effect of T cells that have been conditioned by the proteolytic activity of Der p 1 on IgE synthesis by B cells. METHODS: We have examined this concept in experiments whereby T cells that have been exposed to either proteolytically active or inactive Der p 1 were cocultured with autologous B cells and IgE antibody synthesis was monitored. RESULTS: Here we demonstrate for the first time that coculturing T cells that have been in contact with proteolytically active Der p 1 with autologous B cells leads to augmentation of IgE antibody responses. CONCLUSIONS: The proteolytic activity of Der p 1 conditions human T cells, which then become empowered to trigger enhanced IgE synthesis by B cells.     

Anaplastic ganglioglioma with sarcomatous component: An immunohistochemical study and molecular analysis of p53 tumor suppressor gene

The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).     

Isochromosome 18q in a girl with holoprosencephaly,DiGeorge anomaly,and streak ovaries

We report on the clinical and pathologic findings in a girl with isochromosome 18q (46, XX,i(18q)) who had combined manifestations of monosomy 18p and trisomy 18q. Major congenital anomalies included premaxillary agenesis, alobar holoprosenphaly, double Outlet right ventricle, DiGeorge anomaly and streak ovaries. The clinical spectrum in i(18q) is very broad. © 1993 Wiley-Liss, Inc.     

Diffuse type of senile plaques in the cerebellum of Alzheimer-type dementia demonstrated byβ protein immunostain

Summary We studied senile plaques (SP) in the cerebella of six autopsied subjects with Alzheimer-type dementia (ATD) and ten non-ATD autopsied subjects between the ages of 78 and 90. Neither SP nor amyloid angiopathy (AA) was observed in any of the non-ATD subjects. In the four of the six ATD subjects, diffuse plaques in the molecular layer were seen as ill-defined areas of fine fibrillar materials by protein immunostaining with formic acid pretreatment, the modified Bielschowsky stain, and periodic acid-methenamine silver (PAM) stain. The plaques were not visible with Bodian, Congo red, or periodic acid-Schiff stains. Compact plaques in the Purkinje cell or in the granular cell layers were found in three of the six subjects. Their amyloid core was often surrounded by areolar amyloid deposits. AA was observed in three of the six subjects. The argyrophilia of the diffuse and compact plaques, demonstrated by the modified Bielschowsky and PAM stains, became undetectable when the sections were first treated with formic acid. Such treatment made the plaques immunoreactive with protein antiserum. The findings suggested that cerebellar diffuse plaques and compact plaques consist mainly of an amyloid component, and are characteristic of ATD.     

Differential regulation of cytokine genes in gingival epithelial cells challenged by Fusobacterium nucleatum and Porphyromonas gingivalis

IL-8 mRNA in human gingival epithelial cells (HGECs) is up-regulated by Fusobacterium nucleatum, and up-/down-regulated by Porphyromonas gingivalis in a complex interaction in the early stages (< or = 4 h) after infection. The mechanisms involved in this regulation in response to F. nucleatum and/or P. gingivalis infection, and identification of co-regulated cytokine genes, are the focus of this investigation. Heat, formalin or protease treatment of F. nucleatum cells attenuated the IL-8 mRNA up-regulation. NF-kappaB, mitogen-activated protein kinase (MAPK) p38 and MAPK kinase/extracellular signal-regulated kinase (MEK/ERK) pathways were involved in IL-8 mRNA induction by F. nucleatum. Pretreatment of P. gingivalis with heat, formalin or protease enhanced IL-8 mRNA induction. NF-kappaB, MARK p38, and MEK/ERK pathways were also involved in this induction. In contrast, down-regulation of IL-8 mRNA by P. gingivalis involved MEK/ERK, but not NF-kappaB or MAPK p38 pathways. cDNA arrays analysis revealed that mRNA down-regulation by P. gingivalis is a specific reaction that only a number of genes, e.g. IL-1beta, IL-8, macrophage inflammatory protein-2alpha, and migration inhibitory factor-related protein-14, are affected based on examination of 278 cytokine/receptor genes. These data indicate that F. nucleatum and P. gingivalis trigger specific and differential gene regulation pathways in HGECs.     

Lymphoepithelioma-like carcinoma of the bladder: three cases with clinicopathological and p53 protein expression study

Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma.     

Human papillomavirus infection in Egyptian esophageal carcinoma: correlation with p53, p21, mdm2, C-erbB2 and impact on survival

The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21(waf), c-erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21(waf)and c-erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c-erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21(waf) was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c-erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21(waf). Human papillomavirus infection is frequent in Egyptian EC. Both p53-dependent and p53-independent pathways seem to be involved in HPV-associated EC. mdm2 and c-erbB2 are possible targets for HPV in the p53-independent pathway. However, only advanced stage and aberrant expression of p53 and p21(waf) are independent prognostic markers.