Cutaneous gamma/delta+ T-cell lymphoma (CGD-TCL) is a rare but aggressive lymphoma associated with a poor prognosis in most patients. The clinicopathological spectrum is variable including predominantly epidermotropic infiltrates manifesting with patches and plaques or tumors with dermal and/or subcutaneous infiltrates. The diagnosis of CGD-TCL requires the demonstration of a gamma/delta+ phenotype by immunohistochemistry. We report 2 patients with epidermotropic cutaneous T-cell lymphomas displaying a gamma/delta+ phenotype, but exhibiting an indolent course. In one patient, the clinical presentation was similar to mycosis fungoides in patch and plaque stage, but recurrent blister formation within the lesions was observed accompanied by fever and arthralgias, whereas the second patient presented with 2 localized erosive plaques on the left temple and dense epidermotropic and dermal diffuse and folliculotropic infiltrates of atypical small-to-medium-sized lymphocytes. These cases corroborate the view that expression of a gamma/delta+ phenotype in cutaneous T-cell lymphomas per se does not portend a worse prognosis and that CGD-TCL may represent a clinically and prognostically heterogeneous group.

Cutaneous γ/δ+ T-cell lymphoma (CGD-TCL) is a rare but aggressive lymphoma associated with a poor prognosis in most patients. The clinicopathological spectrum is variable including predominantly epidermotropic infiltrates manifesting with patches and plaques or tumors with dermal and/or subcutaneous infiltrates. The diagnosis of CGD-TCL requires the demonstration of a γ/δ+ phenotype by immunohistochemistry. We report 2 patients with epidermotropic cutaneous T-cell lymphomas displaying a γ/δ+ phenotype, but exhibiting an indolent course. In one patient, the clinical presentation was similar to mycosis fungoides in patch and plaque stage, but recurrent blister formation within the lesions was observed accompanied by fever and arthralgias, whereas the second patient presented with 2 localized erosive plaques on the left temple and dense epidermotropic and dermal diffuse and folliculotropic infiltrates of atypical small-to-medium-sized lymphocytes. These cases corroborate the view that expression of a γ/δ+ phenotype in cutaneous T-cell lymphomas per se does not portend a worse prognosis and that CGD-TCL may represent a clinically and prognostically heterogeneous group.

Cutaneous γ/δ+ T-cell lymphoma (CGD-TCL) is a rare but aggressive lymphoma associated with a poor prognosis in most patients. The clinicopathological spectrum is variable including predominantly epidermotropic infiltrates manifesting with patches and plaques or tumors with dermal and/or subcutaneous infiltrates. The diagnosis of CGD-TCL requires the demonstration of a γ/δ+ phenotype by immunohistochemistry. We report 2 patients with epidermotropic cutaneous T-cell lymphomas displaying a γ/δ+ phenotype, but exhibiting an indolent course. In one patient, the clinical presentation was similar to mycosis fungoides in patch and plaque stage, but recurrent blister formation within the lesions was observed accompanied by fever and arthralgias, whereas the second patient presented with 2 localized erosive plaques on the left temple and dense epidermotropic and dermal diffuse and folliculotropic infiltrates of atypical small-to-medium-sized lymphocytes. These cases corroborate the view that expression of a γ/δ+ phenotype in cutaneous T-cell lymphomas per se does not portend a worse prognosis and that CGD-TCL may represent a clinically and prognostically heterogeneous group.

Background: Direct immunofluorescence (DIF) testing is an important procedure in the diagnosis of autoimmune bullous dermatoses. We investigated the expression of C3d in formalin-fixed, paraffin-embedded tissue of autoimmune bullous dermatoses.Methods: The immunohistochemical expression of C3d in bullous pemphigoid (BP) (n = 32), pemphigoid gestationis (PG) (n = 3), pemphigus (n = 14), dermatitis herpetiformis Duhring (DHD) (n = 10), linear immunoglobulin A (IgA) dermatosis (n = 4), mixed forms of BP and linear IgA dermatosis (n = 2), and 44 controls was analyzed on formalin-fixed tissue.Results: Thirty-one of 32 cases (97%) of BP and 3 out of 3 cases (100%) of PG showed a linear positivity of C3d along the basement membrane. Only 3 out of 14 (21%) cases of pemphigus showed an intraepidermal intercellular expression of C3d. The two mixed forms of linear IgA dermatosis and BP showed a linear positivity of C3d along the basement membrane. All cases of DHD, linear IgA dermatosis and all of the controls were negative for C3d.Conclusions: C3d immunohistochemistry is a valuable tool in the diagnosis of BP and PG of the skin with a sensitivity of at least 97%. Mixed forms of linear IgA dermatosis, and BP, DHD and linear IgA dermatosis can only be identified by DIF. A positive result may prompt serologic confirmation of BP without further need for DIF.

Various skin conditions are considered to be characteristic markers for elevated coronary disease risk. Over and above these established signs there are reports on other skin signs with possible associations with elevated coronary disease risk, i.e. the horizontal earlobe crease, high breast hair density, precocious graying and male pattern hair loss. A review of the literature is presented in this article, and the relevance of these symptoms is discussed as they are related to the possible myocardial disease risk. The available data on this topic are impressive, but on close assessment most of the studies are marred by methodical errors.

Primary cutaneous mucinosis encompasses a wide range of different skin conditions with circumscribed, follicular or diffuse manifestation. For the first time, to our knowledge, we report on the occurrence of so-called "atypical" localized papular mucinosis in the axillary pits of a mother and her (identical) twin daughters presenting as asymptomatic soft minuscule papules. This unique observation allows us to define an autosomal dominant inheritance pattern with a high level of penetrance for this rare skin disease.

The first step of leukocyte extravasation, leukocyte rolling, is mediated by E-, P-, and L-selectins. Mice deficient for alpha-1,3-fucosyltransferase VII (FucTVII)(-/-) are characterized by deficiency of E-, P-, and L-selectin ligand activity. This model system was used to evaluate the role of the interactions of selectins with their ligands in T and B cell responses. In the present study, FucTVII(-/-) mice showed reduced CD4+ T cell-mediated contact hypersensitivity reactions of the ears to FITC as well as reduced CD8+ T cell-mediated delayed-type hypersensitivity reactions of the footpads against lymphocytic choriomeningitis virus infection. As Langerhans cell migration to local lymph nodes as well as CD4+ and CD8+ T cell induction were found to be normal, the afferent arm of these reactions was not impaired. The reduced inflammatory reactions of the skin were due to inefficient lymphocyte extravasation into the skin. In contrast, extravasation of CD4+ and CD8+ T cells into visceral organs, such as the ovaries or the brain, was not impaired in FucTVII(-/-) mice. Elimination of vaccinia virus and of lymphocytic choriomeningitis virus from ovaries and brain, as well as elimination of tumor cells from several visceral organs was normal. Thus, interactions of selectins with their ligands are important for lymphocyte homing into the skin, but not for lymphocyte extravasation into visceral organs.

Polysialic acid, or PSA, is a term used to refer to linear homopolymers of α(2,8)-sialic acid residues displayed at the surface of some mammalian cells. PSA is typically linked to the neural cell adhesion molecule N-CAM, where it can modulate the homotypic adhesive properties of this polypeptide. PSA expression is developmentally regulated, presumably through mechanisms involving regulated expression of sialyltransferases involved in PSA biosynthesis. Several different sialyltransferase sequences have been implicated in PSA expression, although the precise roles of these enzymes in this context remain unclear. One such sequence, termed STX, maintains approximately 59% amino acid sequence identity with another sialyltransferase (PST-1, from hamster; PST, human) that is known to participate in PSA expression. While a murine STX fusion protein can catalyze the synthesis of a single α(2,8)-sialic acid linkage in vitro, the ability of STX to participate in PSA expression in vivo has not been demonstrated. We show here that STX transcripts are present in a PSA-positive, N-CAM-positive human small cell carcinoma line (NCI-H69/F3), but are absent in a variant of this line (NCI-H69/E2) selected to be PSA-negative and N-CAM-positive. To functionally confirm this correlation, we have cloned a human cDNA encoding the human STX sequence, and show, by transfection studies, that human STX can restore PSA expression when expressed in the PSA-negative, N-CAM-positive small cell carcinoma variant. We furthermore show that STX can confer PSA expression when expressed in a PSA-negative, N-CAM-positive murine cell line (NIH-3T3 cells), or when expressed in PSA-negative, N-CAM-negative COS-7 cells. These observations imply that STX, like PST-1/PST, can determine PSA expression in vivo. When considered together with the correlation between STX expression and PSA expression in vivo in the brain, these results suggest a regulatory role for STX in PSA expression in the developing central nervous system and small cell lung carcinoma.