T-cell trafficking plays an essential role in tumor immunity.

Distinct populations of effector memory T cells use different homing receptors to traffic to the skin and gut. Whether tissue-selective T cells are needed for early rejection of a neoplasm growing in these tissues remains an open question. We chose to study an allogeneic tumor model because growth of such a fully mismatched tumor would signify a profound immune deficit. We implanted allogeneic tumor cells in the skin or gut of mice deficient in either α(1,3) fucosyltransferases IV and VII, enzymes critical for generating E-selectin ligands on skin-homing T cells, or ß7 integrin, a component of the α4ß7 integrin ligand for the mucosal adressin MAdCAM. During the first 9 days after tumor implantation, FucTVII-/- mice showed a profoundly impaired capacity to reject tumors growing in the skin, but readily rejected tumors implanted in the gut. Rejection of tumors in the skin was even more impaired in mice deficient in both FucTIV and FucTVII. This impairment was corrected by infusion of T cells from normal mice. By contrast, ß7 integrin-/- mice showed profoundly impaired rejection of tumors in the gut, but no defect in the skin tumor rejection. These differences were unrelated to antigen recognition or effector function of T cells, since all strains of mice were capable of generating tumor-specific CTLs in vitro against the tumor cell line used in vivo. These results demonstrate that T-cell homing defects in vivo impair immune surveillance of peripheral epithelial tissues in a specific and selective fashion.

Eruptive Sebaceous Hyperplasia: A Case Report and Review of the Literature.

Introduction: Eruptive sebaceous hyperplasia (ESH) is a benign process characterized by the acute onset and rapid proliferation of sebaceous glands, typically on the face. Although historically attributed to cyclosporine therapy, the preponderance of reports over the past 2 decades suggests a more complex etiology. There is increasing thought a combination of multiple medications as well as a genetic component contribute to ESH's clinical presentation. Despite these theories, the exact cause of ESH in immunosuppressive therapy is poorly understood. Case Presentation: To our knowledge, we report the third case of ESH arising in multimodality immunosuppressive therapy, consisting of tacrolimus, mycophenolate mofetil, and prednisone, affecting a renal transplant patient. Our patient began cyclosporine monotherapy at an early age but did not see eruption of lesions until years later after following a multimodal therapy. Conclusion: We discuss the association of ESH with other medical conditions and treatments. We hope this case sheds light on a possible complication of multimodal immunosuppressive therapy in renal transplant patients. This will allow patients and providers to be better informed of the pros and cons of different treatment options for immunosuppressive therapy in renal transplant patients.

Clinical and in vitro resistance to bexarotene in adult T-cell leukemia: loss of RXR-alpha receptor.

The oral rexinoid bexarotene (Targretin) is widely used for treatment of cutaneous T-cell lymphomas (CTCL). We recently reported the first case of adult T-cell leukemia/lymphoma (ATLL) that responded rapidly to combination therapy of bexarotene and interferon (IFN)-alpha2b with complete clinical response. We demonstrated that bexarotene induced apoptosis of the patient's malignant peripheral blood T-cells in vitro. However, our patient developed skin and nodal relapse 180 days after starting treatment. We now demonstrate that his peripheral blood malignant T cells became resistant to bexarotene-induced apoptosis. We investigated potential mechanisms that may cause aberrations in the retinoid X receptor (RXR) subunits, RXR-alpha and RXR-beta, to account for these findings. Sequence analysis did not reveal acquisition of mutations in the genes encoding RXR-alpha and RXR-beta by resistant cells. We assessed RXR-alpha and RXR-beta expression by Western blot analysis and found that resistant cells had significantly decreased RXR-alpha expression compared with pretherapy bexarotene-sensitive cells. Our findings indicate that reduced expression of the RXR-alpha receptor subunit may represent a mechanism for resistance to bexarotene in T-cell malignancies.

Serial isolates of persistent Haemophilus influenzae in patients with chronic obstructive pulmonary disease express diminishing quantities of the HMW1 and HMW2 adhesins.

In patients with chronic obstructive pulmonary disease (COPD), the lower respiratory tract is commonly colonized by bacterial pathogens, including nontypeable Haemophilus influenzae. The H. influenzae HMW1 and HMW2 adhesins are homologous proteins that promote bacterial adherence to respiratory epithelium and are the predominant targets of the host immune response. These adhesins undergo graded phase variation, controlled by the numbers of 7-bp repeats upstream of the HMW1 and HMW2 structural genes (hmw1A and hmw2A, respectively). In this study, we examined the levels of HMW1 and HMW2 expressed by H. influenzae isolates collected serially from patients with COPD. We found that expression of HMW1 and HMW2 in a given strain decreased over time in a majority of patients, reflecting progressive increases in the numbers of 7-bp repeats and associated with high serum titers of HMW1/HMW2-specific antibodies. We speculate that the presence of high titers of antibodies against the HMW1 and HMW2 adhesins and other immune factors in the lower respiratory tracts of patients with COPD may result in gradual selection for bacteria with reduced levels of HMW1 and HMW2.

Immunopathogenesis and therapy of cutaneous T cell lymphoma.

Cutaneous T cell lymphomas (CTCLs) are a heterogenous group of lymphoproliferative disorders caused by clonally derived, skin-invasive T cells. Mycosis fungoides (MF) and Sezary syndrome (SS) are the most common types of CTCLs and are characterized by malignant CD4(+)/CLA(+)/CCR4(+) T cells that also lack the usual T cell surface markers CD7 and/or CD26. As MF/SS advances, the clonal dominance of the malignant cells results in the expression of predominantly Th2 cytokines, progressive immune dysregulation in patients, and further tumor cell growth. This review summarizes recent insights into the pathogenesis and immunobiology of MF/SS and how these have shaped current therapeutic approaches, in particular the growing emphasis on enhancement of host antitumor immune responses as the key to successful therapy.

Total skin electron beam therapy may be associated with improvement of peripheral blood disease in Sézary syndrome.

Total skin electron beam radiation is an effective therapy for palliation of the cutaneous symptoms of the most common types of cutaneous T-cell lymphomas, mycosis fungoides and Sézary syndrome. We report 4 cases of patients with Sézary syndrome who had significant improvement in their blood burden of malignant cells in addition to complete cutaneous responses to total skin electron beam therapy. The data from these 4 patients illustrate the potential for total skin electron beam to be used as both a skin and blood tumor debulking agent, and not merely as a palliation for skin symptoms.

Update on the natural history and systemic treatment of psoriasis.

The onset of psoriatic disease and its associated comorbidities involves the interplay among a myriad of genetic and environmental risk factors. As we gain further insight into the immunopathogenesis of psoriasis, we hope it will provide the basis for the development of safer, more efficacious, and more durable therapeutics in the future. Given its enormous toll on patient health and quality of life, steps should be taken to prevent or decrease the risk for psoriasis-associated comorbidities through behavior modification and use of preventative health screenings and treatments. Future studies will need to be performed to determine if successful treatment of psoriasis will lead to a decreased risk for developing psoriasis-associated comorbidities over time.

Synthetic imidazoquinolines potently and broadly activate the cellular immune response of patients with cutaneous T-cell lymphoma: synergy with interferon-gamma enhances production of interleukin-12.

Advanced cutaneous T-cell lymphoma (CTCL) is typically associated with a variety of profound defects of cellular immunity, including depressed dendritic cell numbers and function. Therefore, we investigated the ability of synthetic imidazoquinolines, which are agonists for Toll-like receptors (TLRs) 7 and 8, to enhance in vitro the cell-mediated immunity of patients with leukemic CTCL and Sézary syndrome. Patients' peripheral blood mononuclear cells (PBMCs) stimulated with the TLR7 agonist 3M-001 produced high levels of interferon (IFN)-alpha, and the TLR8 agonist 3M-002 potently induced predominantly interleukin (IL)-12 and IFN-gamma. Marked upregulation of CD69 and CD25 on natural killer (NK) cells and T cells from patients and an increase in NK cytolytic activity was also observed. We further demonstrate that priming of patients' PBMCs with IFN-gamma has the ability to synergistically enhance the production of IL-12 induced by a synthetic agonist for TLR8. The underlying mechanisms of increased IL-12 production in response to priming with IFN appears to involve an increase in IL-12 p35 and IL-12 p40 gene transcription and a decrease in IL-10 levels upon stimulation with the TLR8 agonist. Our data demonstrate the ability of imidazoquinolines to potently stimulate cellular immune responses of patients with CTCL and emphasizes the benefit of using a combination of biologic modifiers to further enhance their immune responses.

Progressive multifocal leukoencephalopathy from JC virus in a patient with advanced mycosis fungoides.

Progressive multifocal leukoencephalopathy is a central nervous system disease due to reactivation of the human polyoma JC virus in immunocompromised patients. Advanced mycosis fungoides patients are intrinsically immunosuppressed and susceptible to infections, but only rarely have been reported to develop progressive multifocal leukoencephalopathy. We report a case of progressive multifocal leukoencephalopathy developing in an advanced mycosis fungoides patient without prior history of immunosuppressive therapy.

High clinical response rate with multimodality immunomodulatory therapy for Sézary syndrome.

PURPOSE: The goal of this study was to evaluate the clinical response rate of patients with Sézary syndrome (SS) to multimodality immunomodulatory therapy consisting of extracorporeal photopheresis in combination with >/= 2 systemic biologic response modifiers (interferon-, interferon-, retinoids, and/or sargramostim) and psoralen plus UV-A. PATIENTS AND METHODS: Twenty-eight patients who met established criteria for SS were treated with multimodality immunomodulatory therapy at the Hospital of the University of Pennsylvania between January 2000 and December 2002. All patients received > 6 cycles of extracorporeal photopheresis. Patients were categorized into groups based on their response to therapy. RESULTS: An overall clinical response of 89% was achieved with multimodality immunomodulatory therapy. Twenty-nine percent of patients exhibited a complete response, characterized by no evidence of cutaneous disease and a Sézary count 5%. Sixty-one percent exhibited a partial response. Eleven percent were nonresponders. CONCLUSION: Based on our experience, multimodality immunomodulatory therapy is an exceptionally effective treatment for SS. The durability of response and impact on overall survival remains to be determined; however, this approach offers an appealing alternative to treatments associated with higher morbidity rates.

Biological effects of bexarotene in cutaneous T-cell lymphoma.

OBJECTIVE: To determine the effects of bexarotene on malignant T cells isolated from the peripheral blood of patients with the leukemic variant of cutaneous T-cell lymphoma (Sézary syndrome). DESIGN, SETTING, AND PARTICIPANTS: Peripheral blood mononuclear cells from 9 patients with Sézary syndrome and a high burden of circulating malignant T cells (>50% of peripheral blood mononuclear cells) and 6 healthy volunteers underwent evaluation at a university medical center, to test the effects of bexarotene on T cells. MAIN OUTCOME MEASURES: The capacity of bexarotene to induce apoptosis and its effects on T-cell cytokine production from peripheral blood lymphocytes isolated from patients with Sézary syndrome. RESULTS: Bexarotene produced dose-dependent apoptosis of peripheral blood T cells from patients with Sézary syndrome. The T cells from approximately two thirds of patients were consistently sensitive to bexarotene, whereas those from the remaining one third of patients were consistently resistant to the apoptotic effects of bexarotene. Bexarotene inhibited mitogen-induced interleukin 4 production by the peripheral blood cells of patients with Sézary syndrome, and this effect correlated with sensitivity of patients' cells to apoptosis. In contrast to the retinoic acid receptor-specific retinoid, all-trans retinoic acid, bexarotene does not induce the augmentation of interferon gamma production. CONCLUSIONS: Bexarotene induces apoptosis of malignant T cells from patients with Sézary syndrome, but the cells from a proportion of patients are resistant to the apoptotic effects. Interleukin 4 production, which can play a role in the systemic immunosuppression that characterizes advancing Sézary syndrome, may be inhibited by bexarotene.

Cytokines and other biologic agents as immunotherapeutics for cutaneous T-cell lymphoma.

Cutaneous T-cell lymphomas (CTCLs) are a group of skin-invasive malignancies of clonally derived T lymphocytes. Mycosis fungoides and Sézary syndrome, characterized by the proliferation of CD4+ T cells, are the most common forms of CTCL. Among these latter disorders, the host antitumor response appears to play an important role in disease control. Thus, systemic therapeutic agents are used in an effort to augment the host antitumor response while selectively targeting the malignant cells. Both new and old biologic response-modifying treatment options currently used to treat CTCL are reviewed.

In vivo imaging of cutaneous T-cell lymphoma migration to the skin.

Cutaneous T-cell lymphoma (CTCL) is characterized by the accumulation of malignant CD4(+) T cells in the skin. Although the expression of adhesion molecules and chemokine receptors on CTCL cells has been studied extensively on ex vivo isolated cells, very little is known about the dynamics and mechanisms of CTCL trafficking in vivo. However, detailed knowledge of the molecular cues mediating CTCL migration may be used to interfere with their homing to the skin. We made use of real-time intravital epifluorescence video and two-photon microscopy to visualize malignant T cells from Sezary syndrome (SS), a leukemic variant of CTCL, in dermal microvessels in mouse ear skin. We found that SS cells rolled along dermal venules in a P-selectin- and E-selectin-dependent manner at ratios similar to CD4(+) memory T cells from normal donors. We furthermore show that the chemokine CCL17/TARC, but not CCL27/CTACK, was sufficient to induce the arrest of SS cells in the microvasculature. However, a combination of both chemokines was required to induce extravasation of SS cells. Together, our experiments delineate the molecular adhesion cascade operant in SS cell homing to the skin in vivo.

IL-21 enhances antitumor responses without stimulating proliferation of malignant T cells of patients with Sézary syndrome.

IL-21, a common gamma-chain cytokine secreted by activated CD4+ T cells, influences both humoral and cell-mediated immune responses through the regulation of T, B, dendritic, and natural killer (NK) cells. Sézary syndrome is an advanced form of cutaneous T-cell lymphoma, a clonally derived malignancy of CD4+ T cells that is characterized by profound defects in host cellular immune function. As a modulator of both innate and adaptive immune responses, IL-21 could play an important role in augmenting cell-mediated immunity in these patients. Normal donor and Sézary syndrome patient peripheral blood mononuclear cells were cultured with IL-21 and tested for CD8+ T- and NK-cell activation, NK-cell cytotoxicity, and tumor cell proliferation and apoptosis. IL-21 resulted in a modest increase in CD8+ T- and NK-cell activation, associated with a marked increase in cytolytic activity against both K562 and malignant CD4+ T-cell targets. Although IL-21 failed to demonstrate pro-apoptotic effects on the malignant CD4+ T cells, it is noteworthy that it had no demonstrable proliferative effects on these cells. Thus, IL-21 may play an important role in enhancing the host immune response of Sézary syndrome patients through the increased cytolytic activity of T and NK cells.

Update on the epidemiology and systemic treatment of psoriasis.

Recent epidemiological observations reveal that the prevalence of psoriasis increases more rapidly in young women compared with young men, and that the prevalence of psoriasis may decrease in the elderly. Emerging evidence suggests that some potentially modifiable exposures, such as smoking, stress and obesity, may increase a patient's risk of developing psoriasis. The evolving literature suggests that psoriasis is associated with multiple other diseases, including cancer, cardiovascular disease, diabetes and psychiatric disease, and that psoriasis itself may be an independent risk factor for developing atherosclerosis and myocardial infarction. The treatment of moderate-to-severe psoriasis is undergoing a revolution with the advent of biological therapies that target the immunopathogenesis of psoriasis, such as tumor necrosis factor-alpha and T-cell function. The pharmacokinetics, pharmacodynamics, efficacy and safety profiles vary among biologicals and, therefore, drug and patient factors are important in selecting the optimum therapy. In this article, we focus on recent developments in the epidemiology and systemic treatment of psoriasis.

Bexarotene blunts malignant T-cell chemotaxis in Sezary syndrome: reduction of chemokine receptor 4-positive lymphocytes and decreased chemotaxis to thymus and activation-regulated chemokine.

The malignant cells in Sezary syndrome express the skin trafficking molecules' cutaneous lymphocyte associated antigen (CLA) and chemokine receptor 4 (CCR4). High levels of the CCR4 ligand, thymus, and activation-regulated chemokine (TARC), have been reported in the blood and skin of patients. The rexinoid X-receptor specific retinoid, bexarotene, has contributed to the resolution of cutaneous disease among patients. To evaluate the effects of bexarotene on skin trafficking molecule expression and chemotaxis, peripheral blood mononuclear cells from Sezary syndrome patients and healthy controls were treated with bexarotene in vitro. CCR4 and CLA expression levels and chemotaxis in response to TARC (6.25 ng/ml) were evaluated among lymphocytes before and after treatment with bexarotene (10 microM). Flow cytometric analysis was performed to evaluate CD4, CD26, CLA, and CCR4 cell surface expression. Transwell migration assays were performed to evaluate chemotaxis to TARC. Prior to treatment, malignant cells exhibited higher CCR4 expression (45-90%) and greater than four times more chemotaxis to TARC compared with healthy controls. After treatment with bexarotene for 36-96 hr, a 28% reduction in CCR4 expression was noted (P < 0.05) among the malignant population with an associated 9% decrease in chemotaxis to TARC (P < 0.05). Our results show that bexarotene may inhibit malignant cell trafficking to the skin through an ability to suppress CCR4 expression among Sezary syndrome lymphocytes.

Congenital and infantile melanoma: review of the literature and report of an uncommon variant, pigment-synthesizing melanoma.

Congenital and infantile types of melanoma are uncommon conditions for which there are limited epidemiologic data. The number of reported cases is small with several ascribed etiologies. We review the literature and report the first documented case, to our knowledge, of pigment-synthesizing melanoma in an infant. Reported cases of congenital and infantile melanoma were identified and categorized on the basis of disease origin. Dermatopathologic specimens from an infant given a diagnosis of pigment-synthesizing melanoma are described. Disease arising from medium and large/giant congenital nevi was most common, whereas reports of de novo and transplacental disease were infrequent. Death of approximately 40% of patients was noted within 18 months of diagnosis. Male infants accounted for approximately 74% of cases. The most commonly affected anatomic sites were the head and neck. The prognosis for congenital and infantile melanoma is poor. The high incidence of head-and-neck involvement and male predominance for disease suggest dispositions for both anatomic disease localization and sex.

The use of cytokines, fusion proteins and antibodies to treat cutaneous T-cell lymphoma.

It has long been known that certain immune augmenting therapeutics, particularly interferon alpha, can exert profound salutary effects on the clinical progress of patients with cutaneous T-cell lymphoma. Emerging evidence that the host immune response may play an important role in the control of this disorder has led to the clinical application of other cytokines including interleukin-12 and interferon gamma. In this review, the authors will summarize current knowledge regarding the use of cytokines, fusion proteins and antibodies for the treatment of cutaneous T-cell lymphoma.