Long-term follow-up of 120 patients with AIDS-related Kaposi's sarcoma treated with interferon alpha-2a

NK Response Correlates with HIV Decrease in Pegylated IFN-α2a-Treated Antiretroviral Therapy-Suppressed Subjects

We previously reported that pegylated IFN-α2a (Peg-IFN-α2a) added to antiretroviral therapy (ART)-suppressed, HIV-infected subjects resulted in plasma HIV control and integrated HIV DNA decrease. We now evaluated whether innate NK cell activity or PBMC transcriptional profiles were associated with decreases in HIV measures. Human peripheral blood was analyzed prior to Peg-IFN-α2a administration (ART, baseline), after 5 wk of ART+Peg-IFN-α2a, and after 12 wk of Peg-IFN-α2a monotherapy (primary endpoint). After 5 wk of ART+Peg-IFN-α2a, immune subset frequencies were preserved, and induction of IFN-stimulated genes was noted in all subjects except for a subset in which the lack of IFN-stimulated gene induction was associated with increased expression of microRNAs. Viral control during Peg-IFN-α2a monotherapy was associated with 1) higher levels of NK cell activity and IFN-γ-induced protein 10 (IP-10) on ART (preimmunotherapy) and 2) downmodulation of NK cell KIR2DL1 and KIR2DL2/DL3 expression, transcriptional enrichment of expression of genes associated with NK cells in HIV controller subjects, and higher ex vivo IFN-α-induced NK cytotoxicity after 5 wk of ART+Peg-IFN-α2a. Integrated HIV DNA decline after immunotherapy was also associated with gene expression patterns indicative of cell-mediated activation and NK cytotoxicity. Overall, an increase in innate activity and NK cell cytotoxicity were identified as correlates of Peg-IFN-α2a-mediated HIV control.

Kaposi's Sarcoma-Associated Herpesvirus-Encoded Viral IL-6 (vIL-6) Enhances Immunoglobulin Class-Switch Recombination

Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic gamma-herpesvirus that causes AIDS-associated Kaposi sarcoma (KS) and several lymphoproliferative disorders. During the humoral immune response antigen-activated mature B cells acquire functional diversification by immunoglobulin heavy chain (IgH) class-switch recombination (CSR). CSR is initiated by activation-induced cytidine deaminase (AID) which targets highly repetitive switch (S)-regions to mediate DNA double-stranded breaks (DSBs) in the IgH locus facilitating intramolecular recombination. Here we show that in the context of cytokine stimulation, CSR is enhanced in murine B cells exposed only to replication-competent KSHV in an environment of KSHV infection, which coincided with elevated AID transcripts. Using murine splenic B cells and the mouse lymphoma CH12F3-2 CSR system, we identified that vIL-6, but not murine IL-6, increased class-switching, which correlated with upregulated AID expression. Together, these data suggest a regulatory role for KSHV vIL-6 in functionally modulating B cell biology by promoting CSR, which may in part explain how KSHV infection influences humoral immunity and affect KSHV pathogenesis.

Cell-Mediated Immunity to Target the Persistent Human Immunodeficiency Virus Reservoir

Effective clearance of virally infected cells requires the sequential activity of innate and adaptive immunity effectors. In human immunodeficiency virus (HIV) infection, naturally induced cell-mediated immune responses rarely eradicate infection. However, optimized immune responses could potentially be leveraged in HIV cure efforts if epitope escape and lack of sustained effector memory responses were to be addressed. Here we review leading HIV cure strategies that harness cell-mediated control against HIV in stably suppressed antiretroviral-treated subjects. We focus on strategies that may maximize target recognition and eradication by the sequential activation of a reconstituted immune system, together with delivery of optimal T-cell responses that can eliminate the reservoir and serve as means to maintain control of HIV spread in the absence of antiretroviral therapy (ART). As evidenced by the evolution of ART, we argue that a combination of immune-based strategies will be a superior path to cell-mediated HIV control and eradication. Available data from several human pilot trials already identify target strategies that may maximize antiviral pressure by joining innate and engineered T cell responses toward testing for sustained HIV remission and/or cure.

Liposomal pegylated doxorubicin versus low-dose recombinant interferon Alfa-2a in the treatment of advanced classic Kaposi's sarcoma; retrospective analysis of three German centers

BACKGROUND

Classic Kaposi's sarcoma (KS) is a rare neoplasm, predominantly occurring in older subjects of Eastern Europe or Mediterranean descent. While single lesions may be treated by simple excision, laser therapy, cryotherapy, or intralesional therapy, advanced or disseminated disease requires systemic treatment. Several studies reported the effectiveness of pegylated liposomal doxorubicin (PLD) and low-dose recombinant interferon alfa-2a (IFNalpha) in the treatment of AIDS-associated KS.

OBJECTIVE

The aim of this retrospective analysis of three German centers was to compare the effectiveness and tolerability of PLD with IFNalpha in patients with advanced classic KS.

METHODS

Retrospective analysis of 18 Caucasian patients who had been treated for histologically proven classic KS, with either with PLD or IFNalpha was performed. Twelve patients received 20 mg/m2 of PLD monthly, and the number of cycles was adapted to the clinical response. Dose reduction or increased cycle length was conducted if toxicity intervened. In 6 patients, 3 million U of IFNalpha was injected subcutaneously 3 times a week. IFNalpha -therapy was adapted according to the clinical response.

RESULTS

In the 12 KS patients treated with PLD, complete response (CR) was achieved in 8 (67 percent), major response (MR) in 3 (25 percent), and minor response (mR) in 1 (8 percent). Stable disease (SD) or progression of disease (PD) was not observed. An initial response was noted after 4-16 weeks of treatment (mean 8.6 weeks), the mean cumulative dose of PLD was 571.5 mg/m2 (range, 40 to 1496 mg/m2), and the mean follow-up was 13 months. Neutropenia (33 percent) related to PLD was the most common adverse event (4/12). Vomiting occurred in 3 (25 percent) patients; none of these were severe. Six patients were treated with IFNalpha. MR was achieved in 1 (17 percent), mR in 4 (67 percent) and SD in 1 of 6 patients (17 percent), neither had CR or PD. An initial response was observed after 8-17 weeks of treatment (mean 12.7 weeks). Fever occurred in 4 patients (67 percent). Flu-like symptoms in 3 patients (50 percent) related to IFNalpha were the most common adverse events. Mean follow-up was 6.3 months. The differences in response to treatment between PLD and IFNalpha, in general, were significant with p < 0.05 (T-test for independent samples). Comparing weeks to respond and treatment efficiency data were significant with p < 0.001 (Fisher's exact): response to PLD was up to one-third faster than IFNalpha. Calculating different stages of response (MR, CR, etc.), PLD also was clearly superior (p = 0.018) to IFNalpha (Fisher's exact).

CONCLUSION

This retrospective analysis of patients with classic KS confirms the efficacy and safety of PLD. The benefits of PLD, including the monthly application, the high response even after previous treatments have failed, and the low rate of side effects even in elderly individuals, outweigh the risks. PLD is superior to IFNalpha and should be considered as an promising option in the treatment of advanced classic KS.

Management of Kaposi sarcoma: the role of interferon and thalidomide

Kaposi sarcoma (KS) remains the most commonly diagnosed cancer in HIV-infected patients. Although several chemotherapeutic agents have proven effective in controlling KS, the growing understanding of the factors contributing to the development of KS has provided a stronger rationale for using noncytotoxic agents that influence the mechanisms involved in KS pathogenesis. Two such agents, interferon and thalidomide, have shown activity against KS in clinical trials and have the potential to influence multiple steps believed to be important in KS development and progression. Studies are ongoing to explore the optimal way to use these agents and their mechanisms of action.

Factors predictive of disease progression and death in AIDS-related Kaposi's sarcoma

BACKGROUND

The natural history of Kaposi's sarcoma (KS) is poorly documented. We attempted to identify factors predictive of progression and survival in HIV-infected patients with KS and CD4+ cell counts greater than 100/microL.

PATIENTS AND METHODS

We studied retrospectively 78 HIV-infected patients diagnosed as having KS between 1989 and 1995. The following variables were assessed as potential predictors of progression and death, in a Cox proportional hazards model: age, sex, ethnic group, transmission group, site of the first KS lesions, duration of KS, concomitant opportunistic infections or malignancies, antiretroviral drug therapy (excluding protease inhibitors), antiherpes treatments, neutrophil counts, CD4+ and CD8+ cell counts, plasma HIV load, p24 antigenaemia, beta2-microglobulinaemia and immunoglobin A and G serum levels.

RESULTS

During a median follow-up of 22 months (3-81 months), KS progressed in 66 of the 78 patients. The median survival time after progression was 68 months (9-126 months). Multivariate analysis identified only visceral KS, a high neutrophil count and a high serum immunoglobulin (Ig) level as independent predictors of progression (P < 0.05). Previous and concomitant opportunistic diseases (P = 0.003) and low CD4+ cell counts (P = 0.013) were independently associated with shorter survival; in contrast KS therapy did not independently influence survival.

CONCLUSION

Progression of KS is predicted by markers of KS severity, while overall survival is best predicted by markers of immunodeficiency (opportunistic diseases and the CD4+ cell count).

Non-human immunodeficiency virus Kaposi's sarcoma can be effectively treated with low-dose interferon-alpha despite the persistence of herpesvirus-8

Three patients, negative for human immunodeficiency virus (HIV), with histologically and polymerase chain reaction-proven non-HIV Kaposi's sarcoma who received low-dose interferon (IFN) as first-line treatment because of disseminated symptomatic disease are reported. Applying 3-18 million IU of IFN-alpha 2a per day, 3 days a week, subcutaneously for 8-20 months, major responses were achieved in all three cases. Tumour regression was observed within 4 months and has continued for 57 and 18 months to date (cases 1 and 2, respectively). Influenza-like symptoms, including fever, headaches and fatigue, were mild side-effects. However, in the third patient interferon injections had to be stopped because of hepatic enzyme elevation. Including this case report, 27 non-HIV Kaposi's sarcoma patients subcutaneously treated with IFN-alpha have been reported in literature. Most therapy regimens included 3-18 million IU IFN-alpha per day for 3 days a week. Twenty of 27 patients, or 74%, responded to therapy, whereas seven patients or 26% had stable or progressive disease. Relapse after IFN withdrawal can occur but is frequently delayed and limited, as in case 1. Following the response to IFN treatment, human herpesvirus-8 DNA was detected in the blood mononuclear cells of all three patients, possibly contributing to future relapses.

Human umbilical cord blood myeloid progenitor cells are relatively chemoresistant: a potential model for autologous transplantations in HIV-infected newborns

Vertical transmission from mother to child occurs in 15-39% of women infected with the human immunodeficiency virus (HIV). Stem cell transplantation has recently been suggested as a potential therapy for patients with HIV infection. We have examined the possible advantages of human cord blood (HUCB) stem cells over bone marrow (BM) stem cells in the treatment of HIV-infected newborns. HUCB myeloid progenitors were found to be statistically more resistant to interferon-alpha (IFN-alpha), cytarabine (ARA-C), and eilatin than BM myeloid progenitor cells grown with IL-3 (P < 0.05). HUCB treated with IFN-alpha, ARA-C, and eilatin demonstrated a significantly higher capacity for self-renewal manifested by delta assay following 7 days in liquid culture. We, therefore, suggest that HUCB purged by anti-HIV drugs may be a source for autologous transplantation in HIV-infected newborns.

Interferon beta transduction of peripheral blood lymphocytes from HIV-infected donors increases Th1-type cytokine production and improves the proliferative response to recall antigens

We are developing a gene therapy method of HIV infection based on the constitutive low production of interferon (IFN) beta. Peripheral blood lymphocytes (PBL) from HIV-infected patients at different clinical stages of infection were efficiently transduced with the HMB-HbHuIFNbeta retroviral vector. The constitutive low production of IFN-beta in cultured PBL from HIV-infected patients resulted in a decreased viral production and an enhanced survival of CD4+ cells, and this protective effect was observed only in the PBL derived from donors having a CD4+ cell count above 200 per mm3. In IFN-beta-transduced PBL from healthy and from HIV-infected donors, the production of the Th1-type cytokines IFN-gamma and interleukin (IL)-12 was enhanced. In IFN-beta-transduced PBL from HIV-infected donors, the production of IL-4, IL-6, IL-10, and tumor necrosis factor alpha was maintained at normal levels, contrary to the increased levels produced by the untransduced PBL. The proliferative response to recall antigens was partially restored in IFN-beta-transduced PBL from donors with an impaired antigen response. Thus, in addition to inhibiting HIV replication, IFN-beta transduction of PBL from HIV-infected donors improves several parameters of immune function.

Drug treatment of HIV-related opportunistic infections

The AIDS epidemic has led to the emergence of several disease entities which in the pre-AIDS era were rare or seemingly innocuous. Experience of treating these diseases varies. In some instances, such as Pneumocystis carinii pneumonia, there is an abundance of published literature to direct our course of action. However, for many of these newly recognised diseases our treatment experience is limited. Furthermore, in many instances, well controlled trials evaluating treatment modalities in the AIDS population are lacking. We have identified 13 disease entities (P. carinii pneumonia, toxoplasmosis, cryptococcosis, histoplasmosis, Mycobacterium tuberculosis, Mycobacterium avium complex, cytomegalovirus, coccidioidomycosis, isosporiasis, candidosis, Kaposi's sarcoma, herpes simplex virus, and varicella zoster virus) and have reviewed the current literature with regard to their treatment.

Perspectives of cytokine treatment in malignant skin tumors

Cytokines have been tested in the treatment of different skin cancers during the last decade, and treatment schedules have been established or proposed for several malignant skin tumors. Preferentially, the interferons and interleukin-2 were found to be effective in treating skin cancers. Interferons alpha and beta have been approved for the treatment of human immunodeficiency virus (HIV)-associated Kaposi's sarcoma, cutaneous T cell lymphoma, and malignant melanoma in several countries. Interferon alpha was found to be most effective in cutaneous T cell lymphoma with 40%-60% overall responses. When combining interferon alpha with psoralens and ultraviolet A (PUVA) or with retinoids, even higher response rates up to 60%-90% were reported, and long-term remissions have been described. A considerable activity of interferon alpha was found in HIV-associated Kaposi's sarcoma with response rates of 30%-50%. The effectiveness of Kaposi's sarcoma's treatment was further improved by combining interferon alpha and zidovudine. Responses to interferon alpha in metastatic malignant melanoma are rather seldom (10%-15%), but a stabilization of the disease with prolonged survival was reported after interferon alpha treatment. Additionally, interleukin-2 was found to be active in metastatic melanoma, with overall response rates of about 20%, and both biological agents were found to have an additive efficacy in combination. Several combined regimens of interferon alpha, interleukin-2, and polychemotherapy have been described in metastatic melanoma, and overall response rates higher than 50% were found with these combined treatment modalities. Interferon alpha and beta were also intralesionally injected into basal cell carcinomas and other epithelial skin cancers, and complete responses were found in more than 80% of tumors treated. Local applications of interferons and interleukin-2 were likewise found to be effective in the treatment of cutaneous melanoma metastases and cutaneous manifestations of Kaposi's sarcoma. Cytokines and their combination with other treatment modalities has greatly enriched the treatment facilities in malignant skin tumors during recent years, and additional new cytokines will be introduced in skin cancer treatment in near future.

Kaposi's sarcoma. Epidemiology, pathogenesis, histology, clinical spectrum, staging criteria and therapy

The acquired immunodeficiency syndrome (AIDS) epidemic has had a profound impact on our understanding of Kaposi's sarcoma (KS). Epidemiologic features suggest a sexually transmitted cofactor in the pathogenesis of AIDS-associated KS (AIDS-KS), and several putative agents have received intense scrutiny. Cell culture studies suggest that the angiogenesis of AIDS-KS is stimulated by both human immunodeficiency virus proteins and growth factors that may be involved in the development and progression of AIDS-KS, thereby providing a rationale for new therapeutic interventions. The dermatologist is uniquely qualified to provide care for the majority of patients with KS, as many patients have cutaneous lesions amendable to local therapy (cryotherapy, intralesional therapy, simple excision). Patients requiring more aggressive local therapy (radiation therapy) or systemic therapies (interferon, chemotherapy) can be easily recognized. Standardized staging criteria provide assistance for determining appropriate local or systemic therapy and for evaluating and comparing responses to new therapies. This article reviews the epidemiology, pathogenesis, histologic features, clinical spectrum, staging criteria, and treatment of KS.

Immune-associated toxicities induced by in vivo and in vitro exposure to interferon-alpha alone or in combination with nucleoside analogs

The present studies examine whether immune-associated toxicities develop in rodents exposed to recombinant human interferon-alpha A/D (rHuIFN-alpha) alone or in combination with anti-retroviral nucleoside analogs. Four findings have emerged from these studies: (1) lymphocyte cell number and functional activity are suppressed after subchronic (1, 8 or 10 day) in vivo exposure to therapeutic doses of rHuIFN-alpha; (2) lymphocyte-associated toxicities lessen as in vivo exposure time to rHuIFN-alpha is extended; (3) T-cell-dependent antibody production is decreased after in vitro exposure of both antigen-specific T- and B-cells to rHuIFN-alpha; and (4) in vivo-induced leukocyte toxicities associated with either rHuIFN-alpha or the nucleoside analogs alone do not synergize when the therapies are combined. These data suggest that certain key immune parameters should be monitored carefully in the early stages of IFN-alpha therapy.