Keratinocytes Present Staphylococcus aureus Enterotoxins and Promote Malignant and Nonmalignant T Cell Proliferation in Cutaneous T-Cell Lymphoma.

Cutaneous T-cell lymphoma is characterized by malignant T cells proliferating in a unique tumor microenvironment dominated by keratinocytes (KCs). Skin colonization and infection by Staphylococcus aureus are a common cause of morbidity and are suspected of fueling disease activity. In this study, we show that expression of HLA-DRs, high-affinity receptors for staphylococcal enterotoxins (SEs), by KCs correlates with IFN-γ expression in the tumor microenvironment.

Synthetic Nucleic Acid Antigens in Localized Scleroderma.

We investigated the impact of synthetic nucleic acid antigens on the autoantibody profiles in patients with localized scleroderma, an autoimmune skin disease. Anti-DNA antibodies, including double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA), are common among autoimmune diseases, such as systemic lupus erythematosus and localized scleroderma. Based on recent studies, we hypothesized that the sequence of nucleic acid antigens has an impact on the autoimmune reactions in localized scleroderma.

Clinical and Histological Characteristics of Mycosis Fungoides and Sézary Syndrome: A Retrospective, Single-centre Study of 43 Patients from Eastern Denmark.

Diagnosis of mycosis fungoides and Sézary syndrome can be very challenging. Clinical and histopathological data for patients with mycosis fungoides and Sézary syndrome in Denmark are limited. A retrospective study was performed in Region Zealand, Denmark from 1990 to 2016.

MicroRNA expression in early mycosis fungoides is distinctly different from atopic dermatitis and advanced cutaneous T-cell lymphoma.

Mycosis fungoides (MF) is the most common variant of cutaneous T-cell lymphoma (CTCL). MF is characterized by chronic inflammation dominated by cluster of differentiation 4-positive (CD4(+)) T-cells and T helper 2 cytokines, and as the malignant T-cell clone is initially elusive, early diagnosis is often impossible. MF usually takes an indolent course, but for unknown reasons may turn into an aggressive disease with a poor prognosis.

Analysis of gene expression profiles of microdissected cell populations indicates that testicular carcinoma in situ is an arrested gonocyte.

Testicular germ cell cancers in young adult men derive from a precursor lesion called carcinoma in situ (CIS) of the testis. CIS cells were suggested to arise from primordial germ cells or gonocytes. However, direct studies on purified samples of CIS cells are lacking.

Histone deacetylase 1, 2, 6 and acetylated histone H4 in B- and T-cell lymphomas.

Aims: Histone deacetylase (HDAC) inhibitors are novel therapeutics in the treatment of peripheral T-cell lymphoma, unspecified (PTCL) and diffuse large B-cell lymphoma (DLBCL), where, for unknown reasons, T-cell malignancies appear to be more sensitive than B-cell malignancies. The aim was to determine HDAC expression in DLBCL and PTCL which has not previously been investigated.

Methods And Results: The expression of HDAC1, HDAC2, HDAC6 and acetylated histone H4 was examined immunohistochemically in 31 DLBCL and 45 PTCL.

Optimizing staining protocols for laser microdissection of specific cell types from the testis including carcinoma in situ.

Microarray and RT-PCR based methods are important tools for analysis of gene expression; however, in tissues containing many different cells types, such as the testis, characterization of gene expression in specific cell types can be severely hampered by noise from other cells. The laser microdissection technology allows for enrichment of specific cell types. However, when the cells are not morphologically distinguishable, it is necessary to use a specific staining method for the target cells.

FOXP3 positive regulatory T-cells in cutaneous and systemic CD30 positive T-cell lymphoproliferations.

The CD30-positive lymphoproliferations encompass a spectrum of disorders that share histological and phenotypic similarities but differ markedly in clinical behaviour. The basis for this diversity is not known, but it has been proposed that immune suppression by cytokines and/or regulatory T-cells (Tregs) may be implicated. In this study, skin biopsies from lymphomatoid papulosis (LyP) (n = 14), primary cutaneous anaplastic large cells lymphoma (C-ALCL) (n = 13) and systemic anaplastic large cells lymphoma (S-ALCL) with (n = 9) or without (n = 6) ALK expression were examined by immunohistology for FOXP3 expression in tumour cells and tumour infiltrating Tregs.

Identification of a gene on chromosome 12q22 uniquely overexpressed in chronic lymphocytic leukemia.

The pathogenesis of chronic lymphocytic leukemia (CLL) is unknown but may involve aberrant activation of signaling pathways. Somatic hypermutations in rearranged immunoglobulin heavy-chain (IgVH) genes allow a division of CLL patients into 2 categories: mutated IgVH genes are associated with an indolent disease, whereas unmutated IgVH genes define an aggressive form. Using differential display to compare gene expression in CLL cells with and without IgVH hypermutations, we identified a novel gene, CLL up-regulated gene 1 (CLLU1), that was highly up-regulated in CLL cells without IgVH hypermutations.

Laser-assisted microdissection of membrane-mounted sections following immunohistochemistry and in situ hybridization.

Laser microbeam microdissection (LMM) is an increasingly important histological technique for obtaining homogeneous cell populations and tissue components in order to analyze target-specific changes in genes, gene expression, and proteins. The quality of data obtained with LMM is heavily dependent on the precision with which the target for microdissection can be identified. Since no cover slip is used during LMM, tissue morphology is poor compared with traditional light microscopy.

Laser-assisted microdissection of membrane-mounted tissue sections.

Biological tissues (in particular those affected by disease) are inherently complex mixtures of different cell types and matrices. This heterogeneity can complicate the interpretation of molecular biological studies performed on whole-tissue extracts if the precise cellular origin of the molecules being tested is not known. Laser-assisted microdissection (LAM) has emerged as a leading histological technique for obtaining samples enriched for specific target cell populations or tissue components for subsequent molecular (especially polymerase chain reaction-based) analysis.

The influence of immunohistochemistry on mRNA recovery from microdissected frozen and formalin-fixed, paraffin-embedded sections.

Laser-assisted microdissection (LAM) is now widely used to obtain specific cell populations from heterogeneous tissues. A major disadvantage of LAM is poor tissue morphology during microscopy, in part because coverslips are not used. Immunohistochemical labeling can improve identification of target cells but may affect the subsequent analysis of the microdissected tissue.

Real-time quantitative PCR of microdissected paraffin-embedded breast carcinoma: an alternative method for HER-2/neu analysis.

We studied the feasibility of using real-time quantitative PCR to determine HER-2 DNA amplification and mRNA expression in microdissected formalin-fixed, paraffin-embedded breast tumors and compared this with standard immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) methods. Study cases (27 carcinomas and 3 ductal breast carcinoma in situ (DCIS) cases) showed varying Her-2 expression as determined by IHC (HercepTest). In carcinomas, there was a good correlation between HER-2 DNA amplification and strong HER-2 protein expression detected by FISH and IHC, respectively.