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(1/103) Hepatosplenic and subcutaneous panniculitis-like gamma/delta T cell lymphomas are derived from different Vdelta subsets of gamma/delta T lymphocytes.

Gamma/delta T cell lymphomas (gamma/delta TCL) represent rare, often aggressive types of T cell malignancy that are clinically and pathologically diverse. Most gamma/delta TCL occur as a hepatosplenic or subcutaneous type. To date, analysis of the T cell receptor delta (TCRS) gene repertoire of hepatosplenic gamma/delta TCL (gamma/delta HSTCL) and subcutaneous panniculitis-like gamma/delta TCL (gamma/delta SPTCL) has been reported only in a limited number of cases. In this study we analyzed 11 gamma/delta HSTCL and 4 gamma/delta SPTCL by polymerase chain reaction and immunostaining to determine their usage of the Vdelta subtypes (Vdelta1-6). It is noteworthy that 10 of 11 gamma/delta HSTCL expressed the Vdelta1 gene. The remaining case also expressed T cell receptor delta (TCRS) as determined by flow cytometry and TCRdelta rearrangement in Southern blot. However, the Vdelta gene expressed by this lymphoma could not be determined, which suggests usage of an as yet unidentified Vdelta gene. In striking contrast to the gamma/delta HSTCL, all 4 gamma/delta SPTCL expressed the Vdelta2 gene. Our data demonstrate that gamma/delta HSTCL are preferentially derived from the Vdelta1 subset of gamma/delta T lymphocytes, whereas gamma/delta SPTCL are preferentially derived from the Vdelta2 subset. The pattern of Vdelta gene expression in HSTCL and SPTCL corresponds to the respective, predominant gamma/delta T cell subsets normally found in the spleen and skin. This finding suggests that gamma/delta TCL are derived from normal gamma/delta T lymphocytes which reside in the affected tissues. Furthermore, the selective, lymphoma type-specific Vdelta gene segment usage may provide a molecular tool to distinguish better among various types of gamma/delta TCL lymphoma particularly in the clinically advanced, widely disseminated cases.  (+info)

(2/103) Mycobacterium marinum dermatitis and panniculitis with chronic pleuritis in a captive white whale (Delphinapterus leucas) with aortic rupture.

A 16-year-old female white whale, Delphinapterus leucas, died after nearly 18 months of chronic lymphopenia and pyogranulomatous dermatitis. Necropsy revealed rupture of the aorta with hemorrhage into the cranial mediastinum and between fascial planes of the ventral neck musculature. Multiple foci of ulcerative dermatitis and panniculitis were present across the thorax and abdomen and surrounded the genital folds. In addition, there was a chronic proliferative pleuritis with over 20 liters of histiocytic exudate in the thoracic cavity. Acid-fast bacteria consistent with Mycobacterium sp. were identified in sections of skin lesions and in cytospins of pleural exudate. Cultures of pleura and 1 skin lesion collected at necropsy yielded sparse growth of an acid-fast bacillus with colony characteristics and morphology consistent with Mycobacterium marinum. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis confirmed the presence of M. marinum DNA in samples of skin. This is the first documented occurrence of mycobacteriosis in a white whale and is a unique presentation of mycobacterial dermatitis and panniculitis with chronic pleuritis in a cetacean. The improved PCR-RFLP protocol utilized in this case unifies techniques from several protocols to differentiate between species of Nocardia and rapidly growing mycobacteria clinically relevant to aquatic animals.  (+info)

(3/103) Pyogranulomatous panniculitis in a cat associated with infection by the Mycobacterium fortuitum/peregrinum group.

A 6-year-old, spayed female, American domestic shorthair was presented with a 10-month history of nodules on the dorsum. Diagnosis of pyogranulomatous panniculitis caused by Mycobacterium fortuitum/peregrinum group was achieved by using tissue culture, chromatography, and histopathologic examination. Pathological findings, diagnosis, and clinical management of the condition are discussed.  (+info)

(4/103) Apoptosis and proliferation in subcutaneous panniculitis-like T-cell lymphoma.

Subcutaneous panniculitis-like T cell lymphoma (SPTCL), designated recently as a distinct clinicopathologic entity in the World Health Organization Classification, is a neoplasm composed of cytotoxic T-cells that preferentially involves subcutaneous adipose tissue. Histologically, SPTCL is characterized by extensive karyorrhectic debris and tumor necrosis suggesting that apoptotic mechanisms are involved in its pathogenesis. We assessed the apoptotic index (AI) and proliferation rate (PR) of 13 cases of SPTCL by TUNEL test and Ki-67 immunostaining, respectively. We also immunohistochemically assessed for expression of BCL-2 (anti-apoptosis), BAX (pro-apoptosis), and P53 and correlated the results with apoptosis and proliferation. We detected a high AI (median 8.1%) in 11 cases of SPTCL, and 12 cases had low BCL-2 and high BAX expression. BCL-2 expression inversely correlated with AI (P <.001) and BAX (P <.001). We found a low PR (cutoff > or = 25%) in eight (61%) cases. There was an inverse correlation between AI and PR (r = -.58, P =.04). Ten cases were assessed for P53; immunostaining results were heterogeneous but P53 expression correlated with large cell cytologic features. Our findings demonstrate that SPTCLs have a high AI that may be explained by differential expression of BCL-2 and BAX in the neoplastic cells.  (+info)

(5/103) Local and systemic effects of an allogeneic tumor cell vaccine combining transgenic human lymphotactin with interleukin-2 in patients with advanced or refractory neuroblastoma.

In murine models, transgenic chemokine-cytokine tumor vaccines overcome many of the limitations of single-agent immunotherapy by producing the sequence of T-cell attraction followed by proliferation. The safety and immunologic effects of this approach in humans were tested in 21 patients with relapsed or refractory neuroblastoma. They received up to 8 subcutaneous injections of a vaccine combining lymphotactin (Lptn)- and interleukin-2 (IL-2)-secreting allogeneic neuroblastoma cells in a dose-escalating scheme. Severe adverse reactions were limited to reversible panniculitis in 5 patients and bone pain in 1 patient. Injection-site biopsies revealed increased cellularity caused by infiltration of CD4+ and CD8+ lymphocytes, eosinophils, and Langerhans cells. Systemically, the vaccine produced a 2-fold (P =.035) expansion of CD4+ T cells, a 3.5-fold (P =.039) expansion of natural killer (NK) cells, a 2.1-fold (P =.014) expansion of eosinophils, and a 1.6-fold (P =.049) increase in serum IL-5. When restimulated in vitro by the immunizing cell line, T cells collected after vaccination showed a 2.3-fold increase (P =.02) of T-helper (TH2)-type CD3+IL-4+ cells. Supernatant collected from restimulated cells showed increased amounts of IL-4 (11.4-fold; P =.021) and IL-5 (8.7-fold; P =.002). Six patients had significant increases in NK cytolytic activity. Fifteen patients made immunoglobulin G (IgG) antibodies that bound to the immunizing cell line. Measurable tumor responses included complete remission in 2 patients and partial response in 1 patient. Hence, allogeneic tumor cell vaccines combining transgenic Lptn with IL-2 appear to have little toxicity in humans and can induce an antitumor immune response.  (+info)

(6/103) Pulmonary nocardiosis with bilateral diffuse granular lung shadows in a patient with subcutaneous panniculitic T-cell lymphoma.

A 40-year-old woman undergoing prednisolone and cyclosporine therapy for subcutaneous panniculitic T-cell lymphoma complained of a cough for a few weeks. A chest X-ray revealed bilateral diffuse granular shadows. Additionally, the patient was discovered to have multiple subcutaneous abscesses. Gram-stained smears of sputum and pus from the abscess showing branched gram-positive rods led to a diagnosis of pulmonary nocardiosis with dissemination to the lungs and subcutaneous tissues. Combination therapy consisting of sulfamethoxazole/trimethoprim and panipenem/betamipron produced rapid improvement of radiographic abnormalities. It is suggested that pulmonary nocardiosis should be considered in the differential diagnosis of diffuse granular shadows on chest X-rays, especially in immunocompromised patients.  (+info)

(7/103) Cytotoxic/natural killer cell cutaneous lymphomas. Report of EORTC Cutaneous Lymphoma Task Force Workshop.

BACKGROUND: Cutaneous lymphomas expressing a cytotoxic or natural killer (NK) cell phenotype represent a group of lymphoproliferative disorders for which there is currently much confusion and little consensus regarding the best nomenclature and classification. METHODS: This study analyzes 48 cases of primary cutaneous lymphoma expressing cytotoxic proteins and/or the NK cell marker, CD56. These cases were collected for a workshop of the European Organization for Research and Treatment of Cancer Cutaneous Lymphoma Task Force, to better clarify the clinical, morphologic, and phenotypic features of these uncommon tumors. RESULTS: Several categories with different clinical and pathologic features were delineated: 1) aggressive, CD8+, epidermotropic, cytotoxic T-cell lymphoma; 2) mycosis fungoides, cytotoxic immunophenotype variant; 3) subcutaneous panniculitis-like T-cell lymphoma; 4) NK/T-cell lymphoma, nasal type; 5) CD4+, NK cell lymphoma; 6) blastoid NK cell lymphoma; (7) intravascular NK-like lymphoma; and 8) cytotoxic, peripheral T-cell lymphoma. CONCLUSIONS: Our data show that primary cutaneous cytotoxic/NK cell lymphomas include distinct groups of diseases, clinically, histologically, and biologically. Because the finding of a cytotoxic phenotype often has prognostic significance, the routine use of cytotoxic markers in the diagnosis and classification of cutaneous lymphomas should be expanded.  (+info)

(8/103) Cytophagic histiocytic panniculitis with atypical lymphocytes in peripheral blood.

A 26-year-old female patient developed high fever, hepatosplenomegaly and subcutaneous nodules. Atypical lymphocytes were present in the peripheral blood. Skin biopsy revealed lobular panniculitis. Bone marrow examination showed prominent phagocytosis by benign histiocytes. The diagnosis of cytophagic histiocytic panniculitis was made, and the disease has been well controlled with oral prednisolone. This is the first report of cytophagic histiocytic panniculitis with atypical lymphocytes in the peripheral blood, which are frequently seen in virus-associated hemophagocytic syndrome. This observation suggests that underlying viral infection may be one factor in the development of cytophagic histiocytic panniculitis.  (+info)