Kevin E. Salhany

Interleukin-12 and interleukin-18 synergistically induce murine tumor regression which involves inhibition of angiogenesis.

The antitumor effect and mechanisms activated by murine IL-12 and IL-18, cytokines that induce IFN-gamma production, were studied using engineered SCK murine mammary carcinoma cells. In syngeneic A/J mice, SCK cells expressing mIL-12 or mIL-18 were less tumorigenic and formed tumors more slowly than control cells. Neither SCK.12 nor SCK.18 cells protected significantly against tumorigenesis by distant SCK cells. However, inoculation of the two cell types together synergistically protected 70% of mice from concurrently injected distant SCK cells and 30% of mice from SCK cells established 3 d earlier. Antibody neutralization studies revealed that the antitumor effects of secreted mIL-12 and mIL-18 required IFN-gamma. Interestingly, half the survivors of SCK.12 and/or SCK.18 cells developed protective immunity suggesting that anti-SCK immunity is unlikely to be responsible for protection. Instead, angiogenesis inhibition, assayed by Matrigel implants, appeared to be a property of both SCK.12 and SCK.18 cells and the two cell types together produced significantly greater systemic inhibition of angiogenesis. This suggests that inhibition of tumor angiogenesis is an important part of the systemic antitumor effect produced by mIL-12 and mIL-18.

Tumor Cell Responses to IFNγ Affect Tumorigenicity and Response to IL-12 Therapy and Antiangiogenesis

Expression of a dominant negative mutant IFNgammaR1 in murine SCK and K1735 tumor cells rendered them relatively unresponsive to IFNgamma in vitro and more tumorigenic and less responsive to IL-12 therapy in vivo. IL-12 induced histologic evidence of ischemic damage only in IFNgamma-responsive tumors, and in vivo Matrigel vascularization assays revealed that while IFNgamma-responsive and -unresponsive tumor cells induced angiogenesis equally well, IL-12 and its downstream mediator IFNgamma only inhibited angiogenesis induced by the responsive cells. IL-12 induced angiogenesis inhibitory activity in the responsive cells, which may be attributable to production of the chemokine IP-10. Thus, IL-12 and IFNgamma inhibit tumor growth by inducing tumor cells to generate antiangiogenic activity.

Subcutaneous panniculitis-like T-cell lymphoma : Clinicopathologic, immunophenotypic, and genotypic analysis of alpha/beta and gamma/delta subtypes

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is an uncommon cutaneous lymphoma that has been proposed as a distinct clinicopathologic entity, but studies of SPTCL are limited. We studied the clinicopathologic, immunophenotypic, and genetic features of 11 SPTCLs. All cases had a variable admixture of pleomorphic small, medium, or large lymphocytes and histiocytes infiltrating the subcutis in a lobular panniculitis-like pattern. A granulomatous reaction was seen in three cases and erythrophagocytosis in four. Karyorrhexis and fat necrosis were present in all cases. Angioinvasion was seen in seven SPTCLs; four had areas of coagulation necrosis. All cases expressed T-cell-associated antigens (CD3epsilon, CD45RO, or CD43) and T-cell receptors (TCR); nine expressed alphabeta TCRs and two expressed gammadelta TCRs. T-cell receptor-gamma, TCRbeta, or TCRdelta genes were clonally rearranged in 8 of 10 cases studied. Both gammadelta SPTCLs expressed Vdelta2+ TCRs and were CD4-, CD8- and CD56+. CD56 was negative in seven of nine alphabeta SPTCLs and inconclusive in the other two. Six of nine alphabeta SPTCLs were CD8+; the CD4/CD8 phenotypes were indeterminate in the other three. Cytolytic granule-associated proteins were expressed by all SPTCLs (11 of 11 were TIA-1+, 4 of 4 were perforin+). In situ hybridization for Epstein-Barr virus-encoded RNA (EBER-1) was negative in all cases. Most patients responded to systemic chemotherapy or local radiation therapy. Seven patients are alive: four without disease (19-73 months) and three with disease (32-72 months); four died: three of disease (3-25 months) and one without disease (42 months). We conclude that SPTCLs are clonal, EBV-, cytotoxic T-cell lymphomas derived from alphabeta T-cells or gammadelta T-cells. The gammadelta SPTCLs appear to be preferentially derived from the Vdelta2+ subset. Subcutaneous panniculitis-like T-cell lymphoma may be rapidly fatal or indolent; local therapy may be appropriate for some patients.

Hepatosplenic αβ T-cell lyrnphomas: A report of 14 cases and comparison with hepatosplenic γδ T-cell lymphomas

Hepatosplenic gammadelta T-cell lymphoma is a distinct entity, characterized by occurrence in young adult males with hepatosplenomegaly, B-symptoms, peripheral blood cytopenias, and no lymphadenopathy; lymphomatous infiltrates in the splenic red pulp, hepatic sinusoids, and bone marrow sinuses; T-cell receptor (TCR) gammadelta chains and a cytotoxic T-cell phenotype; isochromosome 7q; and an aggressive clinical course. In comparison, this study describes the clinicopathologic features of 14 hepatosplenic T-cell lymphomas expressing TCR alphabeta chains. They occurred in 11 women and 3 men with a median age of 36 years. Clinical presentation was similar to that described previously for hepatosplenic gammadelta T-cell lymphomas, except for the female preponderance and age distribution (5 patients younger than 13 years of age and 5 patients older than 50 years of age). Disease distribution was primarily in the splenic red pulp and hepatic sinusoids, although liver infiltrates were largely periportal in four cases. Bone marrow involvement, observed in eight patients, was usually interstitial and/or within the sinuses. Lymph nodes were involved in five patients, although lymphadenopathy was demonstrable in only two. Ten cases were composed of intermediate-size tumor cells with round/oval nuclei, slightly dispersed chromatin, inconspicuous nucleoli, and scant to moderate amounts of cytoplasm. Four lymphomas contained primarily large cells with irregular nuclei, dispersed chromatin, discernible nucleoli, and moderate to abundant cytoplasm. Tumor cells in all 14 lymphomas were cytotoxic alphabeta T-cells; 13 co-expressed natural killer cell-associated antigens and showed T-cell clonality. Three lymphomas were associated with Epstein-Barr virus. Two of four cases had an isochromosome 7q. Eleven patients are dead, eight within a year of diagnosis, and two patients have maintained complete remissions after combination chemotherapy. These data show that hepatosplenic T-cell lymphomas include an alphabeta-subtype. This group, along with the previously recognized gammadelta group, should be recognized as phenotypically heterogeneous subtypes of the same disease entity.

Kikuchi-Fujimoto disease: A benign cause of fever and lymphadenopathy

PURPOSE To describe 6 cases of Kikuchi-Fujimoto disease and to review the literature. PATIENTS AND METHODS Review of 6 patients with biopsy-proven Kikuchi-Fujimoto disease detected at a university hospital over a 5-year period. RESULTS Six patients presented with localized, mild lymph node enlargement. In 3 cases, dramatic fever, chills, weight loss and systemic complaints were present. These features prompted prolonged antibiotic therapy and extensive evaluations of fever of unknown origin before the diagnosis was made by biopsy of the minimally enlarged lymph nodes. The 3 remaining patients were otherwise asymptomatic and well. All 6 subjects recovered without specific therapy. CONCLUSIONS Kikuchi-Fujimoto disease is a recently described cause of benign, self-limited lymphadenopathy that is easily confused histologically and clinically with lymphoma and systemic lupus erythematosis. Clinicians and pathologists must be aware of this condition. Although it is an uncommon cause of fever of unknown origin, early recognition of KFD will minimize potentially harmful and unnecessary evaluations and treatments.

Extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma

BACKGROUND Many regimens are used for cutaneous T-cell lymphoma (CTCL), but with advanced disease response rates and patient survival are not adequate with any current therapy. Recently extracorporeal photochemotherapy (ECP) was proposed as an alternative therapy. OBJECTIVE Our purpose is to present the results of ECP in patients with CTCL refractory to other treatments. METHODS Patients with CTCL received ECP at 3- to 5-week intervals for at least 6 months. All patients except one were in stage T2 (patch/plaque) or higher. Eight patients had extracutaneous disease involving lymph nodes (six patients), bone marrow (five), or Sézary cells (six). The interval between initial symptoms and diagnosis was 5.9 +/- 1.9 years (mean +/- standard error of the mean) and the interval between diagnosis and ECP was 2.2 +/- 0.4 years. RESULTS A complete response (disappearance of all lesions) was obtained in five patients (25%) and a partial response (disappearance of at least 50% of lesions) in six patients (30%). Four patients (20%) showed stabilization of their disease and five progressed (25%). The only variable that predicted responders versus nonresponders was the number of ECP sessions (p < 0.05 by multivariate logistic regression). In contrast, no separate beneficial effect of adjunctive chemotherapy (p > 0.5) or electron beam therapy (p > 0.1) was found. CONCLUSION Long-term ECP may be an effective alternative treatment for CTCL refractory to other therapies and is likely to be even more useful when combined with other modalities.

Hepatosplenic and Subcutaneous Panniculitis-Like γ/δ T Cell Lymphomas Are Derived from Different Vδ Subsets of γ/δ T Lymphocytes

Gamma/delta T cell lymphomas (γ/δ TCL) represent rare, often aggressive types of T cell malignancy that are clinically and pathologically diverse. Most γ/δ TCL occur as a hepatosplenic or subcutaneous type. To date, analysis of the T cell receptor δ (TCRδ) gene repertoire of hepatosplenic γ/δ TCL (γ/δ HSTCL) and subcutaneous panniculitis-like γ/δ TCL (γ/δ SPTCL) has been reported only in a limited number of cases. In this study we analyzed 11 γ/δ HSTCL and 4 γ/δ SPTCL by polymerase chain reaction and immunostaining to determine their usage of the Vδ subtypes (Vδ1–6). It is noteworthy that 10 of 11 γ/δ HSTCL expressed the Vδ1 gene. The remaining case also expressed T cell receptor δ (TCRδ) as determined by flow cytometry and TCRδ rearrangement in Southern blot. However, the Vδ gene expressed by this lymphoma could not be determined, which suggests usage of an as yet unidentified Vδ gene. In striking contrast to the γ/δ HSTCL, all 4 γ/δ SPTCL expressed the Vδ2 gene. Our data demonstrate that γ/δ HSTCL are preferentially derived from the Vδ1 subset of γ/δ T lymphocytes, whereas γ/δ SPTCL are preferentially derived from the Vδ2 subset. The pattern of Vδ gene expression in HSTCL and SPTCL corresponds to the respective, predominant γ/δ T cell subsets normally found in the spleen and skin. This finding suggests that γ/δ TCL are derived from normal γ/δ T lymphocytes which reside in the affected tissues. Furthermore, the selective, lymphoma type-specific Vδ gene segment usage may provide a molecular tool to distinguish better among various types of γ/δ TCL lymphoma particularly in the clinically advanced, widely disseminated cases.

The expression of TIA-1+ cytolytic-type granules and other cytolytic lymphocyte-associated markers in CD30+ anaplastic large cell lymphomas (ALCL): correlation with morphology, immunophenotype, ultrastructure, and clinical features.

Anaplastic large cell lymphomas (ALCL) are a heterogeneous group of CD30+ large cell lymphomas; the most characteristic type have a T or null cell phenotype, often express epithelial membrane antigen (EMA) and cytolytic lymphocyte markers, and often possess a nonrandom t(2;5)(p23;q35) chromosomal translocation. We studied 22 (19 T, 1 null, 2 B cell) ALCL, including four primary cutaneous ALCL (PC-ALCL), for the expression of TIA-1, the cytotoxic T lymphocyte (CTL) or natural killer (NK) cell-associated antigens CD4, CD8, betaF1, TCRdelta1, CD56, and CD57, the ALCL-associated antigens p80 and EMA, and the Hodgkins disease-associated marker CD15 to better define the relationship of these markers to histological subtype, primary site, and patient clinical characteristics. TIA-1 expression was seen in 12 of 20 (60%) T or null cell ALCLs with a cytoplasmic, granular distribution. Ultrastructural studies showed cytotoxic-type granules (dense core, multivesicular, and intermediate types) with TIA-1 localized to granules on immunogold labeling. TIA-1 staining strongly correlated with young patient age (< or = 32 years, P < .05) and EMA expression (P < .05). Excluding the four PC-ALCL cases, TIA-1 staining also correlated with p80 expression (P < .05) in all of the T cell cases. Three CD15+ cases were TIA-1-. TIA-1 expression in T or null cell ALCL was seen in all morphological subtypes (2 of 2 small cell variant, 3 of 4 monomorphic variant, and 7 of 14 pleomorphic variant) and primary tumor sites (6 of 14 nodal, 2 of 4 primary cutaneous, 2 of 2 bone, and 2 of 2 soft tissue). TIA-1+ granules were seen in all subsets: 5 of 6 CD4+, 1 of 2 CD8+, 4 of 8 CD56+, and 1 of 2 CD57+ ALCL. Of note, 4 of 10 T or null cell ALCL expressed gammadelta T-cell receptors (TCR), whereas only 1 of 10 T or null cell ALCL was alphabeta TCR+; TCR were not detected in five cases. TIA-1 was expressed by 3 of 4 gammadelta TCR+ ALCL and 1 of 1 alphabeta TCR+ ALCL. These data support a cytotoxic lymphocyte phenotype in most T or null cell ALCL and suggest that some T cell ALCL are derived from cytolytic CD4+ T cells, gammadelta T cells, or NK-like (CD56+ or CD57+) T cells.

Post-transplant lymphoproliferative disease in children

Abstract: Epstein–Barr virus (EBV)‐driven post‐transplant lymphoproliferative disease (PTLD) is an important cause of morbidity and mortality following transplantation, and it occurs more frequently in children than in adults. Of 22 (5%) children at our institution who developed tissue‐proven PTLD 1–60 months (mean 16.5 months) following organ transplant, 11 died: nine of these 22 patients developed PTLD between 1989 and 1993, and seven (78%) died; the remaining 13 developed PTLD between 1994 and 1998, and four (31%) died (p = 0.08). All nine patients who developed PTLD < 6 months after transplant died, but 11 of 13 patients who manifested disease ≥ 6 months after transplant survived (p = 0.0002). Ten of 11 (91%) survivors, but only two of eight (25%) children who died, had serologic evidence of EBV infection at the time of PTLD diagnosis (p = 0.04). EBV seroconversion identified patients at risk for developing PTLD, but also characterized patients with sufficient immune function to survive EBV‐related lymphoid proliferation. In situ hybridization for EBER1 mRNA was diagnostically helpful because it detected EBV in tissue sections of all 20 patients with B‐cell PTLD, including those with negative serology.

Hepatosplenic gamma-delta T-cell lymphoma as a late-onset posttransplant lymphoproliferative disorder in renal transplant recipients

We report 2 cases of renal transplant recipients in whom hepatosplenic gamma-delta T-cell lymphoma (gamma-delta HSTCL) developed 5 and 10 years after transplantation. Both patients had marked hepatosplenomegaly, B symptoms (weight loss, fever, and night sweats), and abnormal peripheral blood findings, including anemia in both, thrombocytopenia and leukoerythroblastic changes in 1, and leukocytosis in the other. Markedly atypical lymphoid infiltrate of intermediate to large cells was observed in the spleen, liver, and bone marrow. The malignant cells showed typical immunophenotype of gamma-delta T cells (CD2+, CD3+, CD4-, CD8-, CD7+, gamma-delta T-cell receptor-positive, and alpha-beta T-cell receptor-negative) with clonal T-cell receptor gene rearrangement and were of the V-delta-1 subset. In addition, the cells contained a cytolytic granule-associated protein, TIA-1, and Fas ligand, indicating cytotoxic T-cell differentiation. The malignant T cells in both cases were of host tissue origin. Both cases were negative for Epstein-Barr virus genome using Southern blot analysis. The patients did not respond to reduction of immunosuppression. Despite initial response to chemotherapy, both patients died within 6 months of diagnosis. Our findings indicate that gamma-delta HSTCL can occur as a late complication in transplant recipients.