Nermin Halkic

Naturally Acquired MAGE-A10- and SSX-2-Specific CD8+ T Cell Responses in Patients with Hepatocellular Carcinoma

Immunotherapy is being proposed to treat patients with hepatocellular carcinoma (HCC). However, more detailed knowledge on tumor Ag expression and specific immune cells is required for the preparation of highly targeted vaccines. HCC express a variety of tumor-specific Ags, raising the question whether CTL specific for such Ags exist in HCC patients. Indeed, a recent study revealed CTLs specific for two cancer-testis (CT) Ags (MAGE-A1 and MAGE-A3) in tumor infiltrating lymphocytes of HCC patients. Here we assessed the presence of T cells specific for additional CT Ags: MAGE-A10, SSX-2, NY-ESO-1, and LAGE-1, which are naturally immunogenic as demonstrated in HLA-A2+ melanoma patients. In two of six HLA-A2+ HCC patients, we found that MAGE-A10- and/or SSX-2-specific CD8+ T cells naturally responded to the disease, because they were enriched in tumor lesions but not in nontumoral liver. Isolated T cells specifically and strongly killed tumor cells in vitro, providing evidence that these CTL were selected in vivo for high avidity Ag recognition. Therefore, besides melanoma, HCC is the second solid human tumor with clear evidence for in vivo tumor recognition by T cells, providing the rational for specific immunotherapy, based on immunization with CT Ags such as MAGE-A10 and SSX-2.

Portal vein embolization with N-butyl cyanoacrylate before partial hepatectomy in patients with hepatocellular carcinoma and underlying cirrhosis or advanced fibrosis.

PURPOSE To describe the safety, complications, and liver regeneration associated with the left liver after embolization of the right portal vein (PV) in patients with hepatocellular carcinoma (HCC) developed in the setting of advanced liver fibrosis and cirrhosis. MATERIALS AND METHODS Forty patients (31 men, nine women; mean age, 62 years) with HCC underwent PV embolization over a 4-year period. Embolization was performed from a left PV percutaneous access with use of n-butyl cyanoacrylate (NBCA) mixed with iodized oil. Computed tomography (CT) volumetry was performed before and 1 month after PV embolization to measure the left lobe volume as well as the functional liver ratio defined by the ratio between the left lobe and the total liver volume minus tumoral volume. PV pressure and liver enzyme levels were compared before and 1 month after the procedure and complications were registered. Factors potentially affecting regeneration (age, sex, diabetes, chemoembolization, functional liver ratio before PV embolization, and Knodell histologic score) were evaluated by one-way and stepwise regression analysis. RESULTS PV embolization could be achieved successfully in all cases. Two patients had partial PV thrombosis on the 1-month follow-up CT and two patients developed transient ascites after PV embolization. The left lobe volume increase was 41% +/- 32% after PV embolization and the functional liver ratio increased from 28% +/- 10% to 36% +/- 10% (P < .0001). Hypertrophy of the left lobe was greater in patients with a low functional liver ratio before PV embolization and those with an F3 fibrosis score. Other factors had no influence on left lobe regeneration. CONCLUSION PV embolization with use of NBCA is feasible in patients with advanced fibrosis and cirrhosis. Hypertrophy of the left lobe of the liver after PV embolization has a statistically significant correlation with lower functional liver ratio and lower degrees of fibrosis.

Immunological and virological responses in HIV-1-infected adults at early stage of established infection treated with highly active antiretroviral therapy.

ObjectiveTo evaluate the immunological and virological responses to highly active antiretroviral therapy (HAART) in blood and lymphoid compartments of HIV-1-infected patients at an early stage of infection. DesignAn open-label, observational, non-randomized, prospective trial of outpatients attending the Centre of Clinical Investigation in Infectious Diseases, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Switzerland. SubjectsForty-one antiretroviral-naive HIV-1-infected adults with 400 CD4 T cells/μl or greater and 5000 plasma HIV-1-RNA copies/ml or greater were enrolled, and 32 finished the study. Forty-nine HIV-negative individuals were included as controls. All subjects gave written informed consent. InterventionsAll patients received abacavir 300 mg by mouth every 12 h and amprenavir 1200 mg by mouth every 12 h for 72 weeks. Mainoutcome measuresThe extent of immune reconstitution in blood and lymph nodes after 72 weeks of HAART was evaluated, and compared with immunological measures of 49 HIV-negative subjects. ResultsVirus replication was effectively suppressed (−3.5 log10 at week 72). Substantial increments of CD4 T cell count in blood and percentage in lymph nodes were observed over time, and these measures were comparable to HIV-negative subjects by week 24 in blood and by week 48 in lymph nodes. The increase was equally distributed between naive and memory CD4 T cells. Recovery of HIV-specific CD4 responses occurred in 40% of patients. ConclusionThe initiation of HAART at an early stage of established HIV infection induces systemic quantitative normalization of CD4 T cells, a partial recovery of HIV-specific CD4 cell responses, and effective and durable suppression of virus replication.

Enrichment of Human CD4+ Vα24/Vβ11 Invariant NKT Cells in Intrahepatic Malignant Tumors

Invariant NKT cells (iNKT cells) recognize glycolipid Ags via an invariant TCR α-chain and play a central role in various immune responses. Although human CD4+ and CD4− iNKT cell subsets both produce Th1 cytokines, the CD4+ subset displays an enhanced ability to secrete Th2 cytokines and shows regulatory activity. We performed an ex vivo analysis of blood, liver, and tumor iNKT cells from patients with hepatocellular carcinoma and metastases from uveal melanoma or colon carcinoma. Frequencies of Vα24/Vβ11 iNKT cells were increased in tumors, especially in patients with hepatocellular carcinoma. The proportions of CD4+, double negative, and CD8α+ iNKT cell subsets in the blood of patients were similar to those of healthy donors. However, we consistently found that the proportion of CD4+ iNKT cells increased gradually from blood to liver to tumor. Furthermore, CD4+ iNKT cell clones generated from healthy donors were functionally distinct from their CD4− counterparts, exhibiting higher Th2 cytokine production and lower cytolytic activity. Thus, in the tumor microenvironment the iNKT cell repertoire is modified by the enrichment of CD4+ iNKT cells, a subset able to generate Th2 cytokines that can inhibit the expansion of tumor Ag-specific CD8+ T cells. Because CD4+ iNKT cells appear inefficient in tumor defense and may even favor tumor growth and recurrence, novel iNKT-targeted therapies should restore CD4− iNKT cells at the tumor site and specifically induce Th1 cytokine production from all iNKT cell subsets.

Predicting the duration of antiviral treatment needed to suppress plasma HIV-1 RNA

Effective therapeutic interventions and clinical care of adults infected with HIV-1 require an understanding of factors that influence time of response to antiretroviral therapy. We have studied a cohort of 118 HIV-1-infected subjects naive to antiretroviral therapy and have correlated the time of response to treatment with a series of virological and immunological measures, including levels of viral load in blood and lymph node, percent of CD4 T cells in lymph nodes, and CD4 T-cell count in blood at study entry. Suppression of viremia below the limit of detection, 50 HIV-1 RNA copies/mL of plasma, served as a benchmark for a successful virological response. We employed these correlations to predict the length of treatment required to attain a virological response in each patient. Baseline plasma viremia emerged as the factor most tightly correlated with the duration of treatment required, allowing us to estimate the required time as a function of this one measure.

Laparoscopic Cholecystectomy as a Day Surgery Procedure: Implementation and Audit of 136 Consecutive Cases in a University Hospital

Laparoscopic cholecystectomy (LC) has been routinely performed since 1989 at our institution, and patients were traditionally admitted for 2 days. In 1996 we implemented a protocol for LC as a day surgery procedure at our center. Although initially reported by others, it has not yet been introduced as routine in Switzerland. The objective of this prospective study was to determine acceptability and safety of LC as an outpatient procedure in a university hospital. Data were collected prospectively for 136 LCs between January 1996 and December 2001. Patients were selected for the study if they wanted to go home within less than 24 hours, had no previous jaundice, and had no anesthetic contraindication. Systematic preoperative liver function tests and hepatic ultrasonography were performed. All patients were admitted on the day of operation. LC was performed using a three-trocar technique. Systematic cholangiography was performed, and all the procedures were completed laparoscopically. There were no common bile duct explorations. Postoperative complications were the following: nausea in seven patients, a minor umbilical hematoma in two. According to patient preference, 101 (74%) were discharged after an overnight stay (less than 24 hours) and 32 (24%) on the same day. The unplanned admission rate was 2%, and none of the patients was subsequently readmitted. The reasons for unplanned admissions were two patients with persistent nausea and one patient for whom an overnight stay was scheduled who presented with a ruptured subcapsular hematoma of the liver. Altogether, 97% of the patients were satisfied with the care they received. Operative costs were not significantly different when comparing inpatient and outpatient LC. The main postoperative savings were in the postoperative costs. Our results confirm that LC as a day surgery procedure is safe, effective, and acceptable to patients and their relatives. These results were achieved by using selection criteria that considered not only the surgical pathology but also the individual and by using appropriate techniques and planned postoperative analgesia.

Combined laparoscopic-endoscopic method using an omental plug for therapy of gastroduodenal ulcer perforation

BACKGROUND Laparoscopic techniques have been proposed as an alternative to open surgery for therapy of peptic ulcer perforation. They provide better postoperative comfort and absence of parietal complications, but leakage occurs in 5% of cases. We describe a new method combining laparoscopy and endoluminal endoscopy, designed to ensure complete closure of the perforation. METHODS Six patients with anterior ulcer perforations (4 duodenal, 2 gastric) underwent a concomitant laparoscopy and endoluminal endoscopy with closure of the orifice by an omental plug attracted into the digestive tract. RESULTS All perforations were sealed. The mean operating time was 72 minutes. The mean hospital stay was 5.5 days. There was no morbidity and no mortality. At the 30-day evaluation all ulcers but one (due to Helicobacter pylori persistence) were healed. CONCLUSIONS This method is safe and effective. Its advantages compared with open surgery or laparoscopic patching as well as its cost-effectiveness should be studied in prospective randomized trials.

Adjuvant intra-arterial hepatic fotemustine for high-risk uveal melanoma patients.

Uveal melanoma metastases occur most commonly in the liver. Given the 50% mortality rate in patients at high risk of developing liver metastases, we tested an adjuvant intra-arterial hepatic (i.a.h.) chemotherapy with fotemustine after proton beam irradiation of the primary tumour. We treated 22 high-risk patients with adjuvant i.a.h. fotemustine. Planned treatment duration was 6 months, starting with four weekly doses of 100 mg/m2, and after a 5-week rest, repeated every 3 weeks. The survival of this patient group was compared with that of a 3 : 1 matched control group randomly selected from our institutional database. Half of the patients experienced ≥grade 3 hepatotoxicity (one patient developing cholangitis 8 years later). Catheter-related complications occurred in 18%. With a median follow-up of 4.6 years for the fotemustine group and 8.5 years for the control group, median overall survival was 9 years [95% confidence interval (CI) 2.2–12.7] and 7.4 years (95% CI 5.4–12.7; P=0.5), respectively, with 5-year survival rates of 75 and 56%. Treatment with adjuvant i.a.h. fotemustine is feasible. However, toxicities are important. Although our data suggest a survival benefit, it was not statistically significant. Confirming such a benefit would require a large, internationally coordinated, prospective randomized trial.

Idiopathic segmental infarction of the greater omentum: A rare cause of acute abdomen

Idiopathic segmental infarction of the greater omentum is a rare cause of acute abdomen. Patients, typically children or obese males in their fifties, present with abdominal pain located in the right upper or lower quadrant, mimicking cholecystitis and appendicitis. CT scanning and ultrasound imaging both may show a well-circumscribed soft tissue mass. Retrospective review of all patients treated for idiopathic segmental infarction of the greater omentum occurred from January 1993 to December 2001. Nine patients were treated successfully, six surgically and three medically. Conservative management of segmental infarction of the greater omentum can be proposed when correctly diagnosed by ultrasound imaging or CT scanning and the patient’s condition is stable. If not, laparoscopic removal of the involved segment of the greater omentum is the treatment of choice.

Molecular and immunological evaluation of the expression of cancer/testis gene products in human colorectal cancer

Tumor-specific gene products, such as cancer/testis (CT) antigens, constitute promising targets for the development of T cell vaccines. Whereas CT antigens are frequently expressed in melanoma, their expression in colorectal cancers (CRC) remains poorly characterized. Here, we have studied the expression of the CT antigens MAGE-A3, MAGE-A4, MAGE-A10, NY-ESO-1 and SSX2 in CRC because of the presence of well-described HLA-A2-restricted epitopes in their sequences. Our analyses of 41 primary CRC and 14 metastatic liver lesions confirmed the low frequency of expression of these CT antigens. No increased expression frequencies were observed in metastatic tumors compared to primary tumors. Histological analyses of CRC samples revealed heterogeneous expression of individual CT antigens. Finally, evidence of a naturally acquired CT antigen-specific CD8+ T cell response could be demonstrated. These results show that the expression of CT antigens in a subset of CRC patients induces readily detectable T cell responses.