Félix Agbalika

Prospective Study of Rituximab in Chemotherapy-Dependent Human Immunodeficiency Virus–Associated Multicentric Castleman's Disease: ANRS 117 CastlemaB Trial

PURPOSE Single-agent chemotherapy is usually effective in HIV-associated multicentric Castlemans disease (MCD). However, in most patients, chemotherapy cannot be discontinued. PATIENTS AND METHODS To evaluate the efficacy of four weekly rituximab infusions (375 mg/m(2)) after discontinuation of chemotherapy in HIV-associated MCD, 24 patients were enrolled onto a prospective open-label trial. RESULTS At study entry, the median time from MCD diagnosis was 21 months. All patients had stable disease on chemotherapy and were dependent on chemotherapy for a median time of 13 months. The median CD4 cell count was 270 x 10(6)/L, and the plasma HIV RNA was less than 50 copies/mL in 18 patients. One patient died with progressive disease at day 15, and 23 patients completed the four cycles of rituximab. Sustained remission (SR) off treatment at day 60 (primary end point) was achieved in 22 patients (92%). From day 60 to day 365, one patient died with acute respiratory failure of undetermined origin, and four patients experienced relapse. Seventeen patients (71%) were alive in SR at day 365 without specific treatment, and the overall survival rate was 92% (95% CI, 71% to 98%). Rituximab was well tolerated, and the majority of adverse events were mild to moderate infections. Mild exacerbation of Kaposis sarcoma (KS) lesions was observed in eight of 12 patients with previous KS. CONCLUSION Rituximab was both effective and safe in HIV-infected patients with chemotherapy-dependent MCD.

Human herpes virus-8 and other risk factors for Kaposi's sarcoma in kidney transplant recipients

Background. The exact reasons for the high incidence of Kaposis sarcoma (KS) after kidney transplantation are still unknown. Immunosuppression is classically considered as the main risk factor, but the relative risk contributed by the patients geographic origin and by human herpes virus (HHV)-8 infection still has to be determined. Methods. We carried out a retrospective and a prospective study among kidney transplant recipients (TP) to identify the risk factors for posttransplantation KS. Each of 30 KS patients was matched with two controls to investigate the association with geographic origin, immunosuppressive regimen, HHV-8 antibodies before and after transplantation, and other infections. Among TP with new onset of KS, we prospectively evaluated HHV-8 serology and viremia in response to decreased immunosuppression. Results. African and Middle East origins, past infection with hepatitis B, hemoglobin level <12 g/dl, lymphocyte count <750/mm 3 at the time of diagnosis and initial use of polyclonal antilymphocyte sera were risk factors for KS. After multivariate analysis, origin in Africa or Middle East and use of antilymphocyte sera for induction remained as independent risk factors. Sixty-eight percent (17/25) of TP with HHV-8 antibodies before or after transplantation developed KS compared with 3% (1/33) of seronegative TP (P<0.00001). HHV-8 DNA was detectable in seven of nine peripheral blood mononuclear cells (PBMC) and in six of six KS lesions at diagnosis; it became negative in PBMC in three of five patients in parallel with tumor regression. Conclusion. African and Middle East geographic origins, HHV-8 infection before and after kidney transplantation, and initial use of polyclonal antilymphocyte sera were independent risk factors for KS. The presence of HHV-8 antibodies before or after transplantation was highly predictive of the emergence of posttransplantation KS and conferred a 28-fold increased risk of KS (odds ratio=28.4; 95% confidence interval: 4.9-279). Detection of HHV-8 DNA within PBMC and KS lesions seems related to tumor burden and evolution.

Epstein-Barr virus (EBV) reactivation in allogeneic stem-cell transplantation: relationship between viral load, EBV-specific T-cell reconstitution and rituximab therapy.

Background. Monitoring of Epstein-Barr virus (EBV) reactivation after allogeneic hematopoietic stem-cell transplantation markedly improved with quantitative real-time polymerase chain reaction amplification of EBV DNA and visualization of EBV-specific CD8+ T cells with peptide-human leukocyte antigen (HLA) class I tetramers. We decided to combine these methods to evaluate posttransplant EBV reactivation and rituximab therapy. Methods. We followed 56 patients treated with an HLA-genoidentical sibling (n=32), an HLA-matched unrelated donor (MUD, n=19), or an unrelated cord-blood transplant (n=5). EBV DNA was quantified in plasma and in peripheral blood mononuclear cells (PBMC). Patient CD8+ T cells were stained with a panel of eight tetramers. Results. EBV DNA was detected in half of the patients, mainly in the MUD group (17/19). In 19 patients, viral DNA was detected only in the cellular compartment. All patients who controlled reactivation without rituximab and despite a viral load of greater than 500 genome equivalents (gEq)/150,000 PBMC mounted an EBV-specific CD8+ T-cell response in greater than 1.4% of CD3+CD8+ T cells. Plasmatic EBV genome was found in nine patients preceded by a high cellular viral load. Three of these patients controlled the reactivation before or without the introduction of rituximab, and they all developed a significant and increasing EBV-specific T-cell response. Patients with EBV-specific T cells at the onset of reactivation controlled viral reactivation without rituximab. Conclusion. This study emphasizes the benefit of an early and close monitoring of EBV reactivation and CD8+-specific immune responses to initiate rituximab only when necessary and before the immune response becomes overwhelmed by the viral burden.

Prognostic Value of Quantitative Kaposi Sarcoma–Associated Herpesvirus Load in Posttransplantation Kaposi Sarcoma

Organ transplant recipients have a higher risk of Kaposi sarcoma (KS). A quantitative real-time polymerase chain reaction assay was developed to evaluate KS-associated herpesvirus (KSHV) as a prognostic tool in transplant recipients with KS. Forty-three patients who developed KS after transplantation were included in a cross-sectional study to correlate virus load with transplantation or KS parameters. Seventeen patients (40%) had KSHV viremia (>100 copies/microg of DNA; median, 6067 copies/microg of DNA). Factors associated with these levels of viremia by univariate analysis were progression of KS (P=.00002), time from KS diagnosis (P=.0007), actual stage of KS (P=.006), initial stage of KS (P=.22), graft loss (P=.013), and time from transplantation (P=.0246). Disease progression remained associated with KSHV viremia in a multivariate analysis (P=.01). Thus, quantification of KSHV load in peripheral blood mononuclear cells could represent a useful tool for monitoring transplant recipients with KS.

Ketosis-Prone Type 2 Diabetes Mellitus and Human Herpesvirus 8 Infection in Sub-Saharan Africans

CONTEXT An atypical form of type 2 diabetes mellitus (DM-2) is revealed by ketosis (ketosis-prone type 2 diabetes mellitus), frequently occurring in individuals who are black and of African origin, and characterized by an acute onset requiring transient insulin therapy. Its sudden onset suggests precipitating factors. OBJECTIVE To investigate the putative role of human herpesvirus 8 (HHV-8) in the pathogenesis of ketosis-prone DM-2. DESIGN, SETTING, AND PARTICIPANTS A cross-sectional study in which antibodies were searched against latent and lytic HHV-8 antigens using immunofluorescence. The presence of HHV-8 in genomic DNA was investigated in 22 of the participants at clinical onset of diabetes. We also tested whether HHV-8 was able to infect human pancreatic beta cells in culture in vitro. The study was conducted at Saint-Louis University Hospital, Paris, France, from January 2004 to July 2005. All participants were black and of African origin: 187 were consecutive diabetic patients of whom 81 had ketosis-prone DM-2 and 106 had nonketotic DM-2, and 90 individuals were nondiabetic control participants who were matched for age and sex. MAIN OUTCOME MEASURES Seroprevalence of HHV-8 and percentage of patients with HHV-8 viremia at onset in ketosis-prone DM-2. RESULTS HHV-8 antibodies were found in 71 patients (87.7%) with ketosis-prone DM-2 vs 16 patients (15.1%) with nonketotic DM-2 (odds ratio, 39.9; 95% confidence interval, 17.1-93.4; P < .001) and 36 of the control participants (40.0%) (odds ratio, 10.7; 95% confidence interval, 4.9-23.4; P < .001). HHV-8 in genomic DNA was present in 6 of 13 patients with ketosis-prone DM-2 tested at acute onset and in 0 of 9 patients with nonketotic DM-2. HHV-8 proteins were present in human islet cells that were cultured for 4 days in the presence of HHV-8. CONCLUSIONS In this preliminary cross-sectional study, the presence of HHV-8 antibodies was associated with ketosis-prone DM-2 in patients of sub-Saharan African origin. Longitudinal studies are required to understand the clinical significance of these findings.

Human Herpesvirus 8-Associated Hemophagocytic Lymphohistiocytosis in Human Immunodeficiency Virus-Infected Patients

We retrospectively reviewed 5 cases of hemophagocytic lymphohistiocytosis (HL) associated with human herpesvirus 8 (HHV-8) reactivation in human immunodeficiency virus (HIV)-infected patients. All patients had clinical and biological features characteristic of HL. Pulmonary symptoms were present in all patients and were frequently life threatening. The mean number of HL episodes was 6. Four patients had HL-associated Kaposi sarcoma, and 3 had multicentric Castleman disease. The mean CD4 cell count was 200 cells/mm(3). HIV loads were stable in all patients. All patients had high levels of HHV-8 in peripheral blood mononuclear cells during attacks, and a significant increase in this parameter before the attacks was seen in 3 patients. Although 2 patients died of HL, 3 are still alive and receiving etoposide therapy (mean follow-up, 3 years). HHV-8-related HL is associated with life-threatening symptoms and biological HHV-8 reactivation, and it may be controlled in the long term by etoposide therapy combined with highly active antiretroviral therapy.

STAT3 transcription factor is constitutively activated and is oncogenic in nasal-type NK/T-cell lymphoma

Nasal-type natural killer (NK) cell lymphoma is an infrequent aggressive malignant disease with very poor prognosis. We aimed to explore the possible role of the transcription factor STAT3 in the pathophysiology of this malignancy, as it was involved in oncogenesis and chemoresistance. For this, we established and characterized a continuous interleukin 2-dependent NK cell line (MEC04) from a patient with a fatal nasal-type NK-cell lymphoma. Cells harbored poor cytotoxic activity against K562 cells, and spontaneously secreted interferon-γ, interleukin-10 and vascular-endothelium growth factor in vitro. STAT3 was phosphorylated in Y705 dimerization residue in MEC04 cells and restricted to the nucleus. Y705 STAT3 phosphorylation involved JAK2, as exposure of cells to AG490 inhibitor inhibited Y705 STAT3 phosphorylation. By using recombinant transducible TAT-STAT3-β (β isoform), TAT-STAT3Y705F (a STAT3 protein mutated on Y705 residue, which prevents STAT3 dimerization) and peptides inhibiting specifically STAT3 dimerization, we inhibited STAT3 phosphorylation and cell growth, with cell death induction. Finally, STAT3 was phosphorylated in Y705 residue in the nuclei of lymphoma cells in eight/nine patients with nasal-type NK/T-cell lymphoma and in YT, another NK cell line. Our results suggest that STAT3 protein has a major role in the oncogenic process of nasal-type NK-cell lymphomas, and may represent a promising therapeutical target.

Patterns of Cytomegalovirus Reactivation Are Associated with Distinct Evolutive Profiles of Immune Reconstitution after Allogeneic Hematopoietic Stem Cell Transplantation

T cell-mediated immunity is essential for the control of cytomegalovirus (CMV) infections in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our aims were to identify patterns of CMV-specific immune responses associated with multiple or prolonged reactivations. We analyzed findings in 116 recipients during the course of infection or reactivation and latency. CD8(+) T cell responses were determined weekly, using HLA class I tetramers together with extended phenotypic analyses. Our results confirmed that recipients of allo-HSCT from unrelated donors were more susceptible to multiple reactivations and that the donors CMV serological status influenced the occurrence of prolonged reactivations. We found that a lack of CMV-specific T cells after the first episode of reactivation was associated with multiple subsequent reactivations. In patients with uncontrolled reactivations, CMV-specific T cells of the late differentiation phenotype CD45RA(+)CD27(-)CD28(-) did not develop. Longitudinal evaluation of CD27 and CD45RA expression within the tetramer-positive subset could help identify patients in whom a protective immune response is developing. Evaluation of CMV-specific immune responses during the first episode of reactivation, together with extended phenotypes, could thus improve immune monitoring, especially in recipients at risk of uncontrolled viral reactivation.

Long-term Follow-up of Non-HIV Kaposi's Sarcoma Treated With Low-Dose Recombinant Interferon Alfa-2b

BACKGROUND AND DESIGN We reviewed the follow-up of 16 patients with Kaposis sarcoma not related to human immunodeficiency virus (13 with classic Kaposis sarcoma and three with endemic Kaposis sarcoma; median age, 58 years) treated by low-dose recombinant interferon alfa-2b (5 million U three times weekly for at least 6 months). RESULTS One patient had a complete response, nine had a major response, three had stable disease, and one had a minor response. Visceral disease stabilized and symptoms improved in three patients. Limited relapse was noted in four patients after withdrawal of interferon. CONCLUSION Our results confirm the efficacy and safety of low-dose recombinant interferon alfa-2b in the long-term treatment of both cutaneous and visceral lesions of Kaposis sarcoma not related to human immunodeficiency virus.

Kaposi's sarcoma in HIV-negative men having sex with men.

Background:Four epidemiologic forms of Kaposis sarcoma have been described, all of which are associated with the human herpesvirus-8. In western countries, human herpesvirus-8 is more prevalent in homosexual men than in the general population, and anecdotal cases of Kaposis sarcoma in HIV-negative homosexual men have been reported. Patients and methods:We included HIV-negative homosexual and bisexual male patients with histologically proven Kaposis sarcoma in a retrospective study. Clinical data were collected using a standardized form. Risk factors for human herpesvirus-8 infection and for the development of Kaposis sarcoma were systematically recorded. Results:Between 1995 and 2007, 28 men met the defined inclusion criteria. Mean age at first symptoms of Kaposis sarcoma was 53 years. Clinical presentation resembled classical Kaposis sarcoma, with limited disease in most patients. No cellular or humoral immunodeficiency was observed. Serologic tests for human herpesvirus-8 (latent immunofluorescence assay) were positive in 88% of patients, and only two patients displayed human herpesvirus-8 viremia at the time of Kaposis sarcoma diagnosis. Three patients developed lymphoproliferative disorders (Castleman disease, follicular lymphoma and Burkitt lymphoma). In this population, α-interferon was well tolerated and gave a complete response, but most patients require only local treatment, if any. Conclusion:Kaposis sarcoma may develop in homosexual or bisexual men without HIV infection. This type of Kaposis sarcoma has clinical features in common with classical Kaposis sarcoma but occurs in younger patients. Its prognosis is good, as Kaposis sarcoma is generally limited, but clinicians should be aware of the association with lymphoproliferative diseases, which may affect prognosis.