Higher Efficiency of Percutaneous Microwave (MWA) Than Radiofrequency Ablation (RFA) in Achieving Complete Response in Cirrhotic Patients with Early Hepatocellular Carcinoma

Background: Contrasting data are available in the literature regarding the superiority of percutaneous microwave ablation (MWA) or radiofrequency ablation (RFA) in very early or early (BCLA 0 or A) hepatocellular carcinoma (HCC). Aims: The primary outcome was to compare the efficacy of RFA and MWA in achieving complete response in cirrhotic patients with early and very early HCC. The secondary outcomes were to evaluate the overall survival and the recurrence rate. Methods: A retrospective, observational, single-center study was performed. Inclusion criteria were liver cirrhosis, new diagnosis of a single node of HCC measuring a maximum of 50 mm or up to three nodules with diameter up to 35 mm, treatment with RFA or MWA. Radiological response was evaluated with multiphasic contrast-enhanced Computed Tomography or Magnetic Resonance Imaging at 5–7 weeks after thermal ablation. Complete response was defined when no vital tissue was detected after treatment. Results: Overall, 251 HCC patients were included in this study; 81 patients were treated with MWA and 170 with RFA. The complete response rate was similar in MWA and RFA groups (out of 331 nodules, 87.5% (91/104) were treated with MWA and 84.2% (186/221) were treated with RFA, p = 0.504). Interestingly, a subanalysis demonstrated that for 21–35 mm nodules, the probability to achieve a complete response using MWA was almost 5 times higher than for RFA (OR = 4.88, 95% CI 1.37–17.31, p = 0.014). Moreover, recurrence rate in 21–35 mm nodules was higher with RFA with respect to MWA (31.9% versus 13.5%, p = 0.019). Overall survival was 80.4% (45/56) when treated with MWA and 62.2% (56/90) when treated with RFA (p = 0.027). No significant difference was observed between MWA and RFA treatment in the 15–20 mm nodules group. Conclusion: This study showed that MWA is more efficient than RFA in achieving complete response in HCC nodules with 21 to 35 mm diameter.     

Early gamma interferon and interleukin-2 responses to vaccination predict the late resting memory in malaria-naïve and malaria-exposed individuals

Two different cell populations respond to potent T-cell-inducing vaccinations. The induction and loss of effector cells can be seen using an ex vivo enzyme-linked immunospot (ELISPOT) assay, but the more durable resting memory response is demonstrable by a cultured ELISPOT assay. The relationship of the early effector response to durable resting memory is incompletely understood. Effector phenotype is usually identified by gamma interferon (IFN-gamma) production, but interleukin-2 (IL-2) has been specifically linked to the differentiation of memory cells. Here, IFN-gamma- and IL-2-secreting effector cells were identified by an ex vivo ELISPOT assay 1 week after vaccination and compared with the resting memory responses detected by a cultured ELISPOT assay 3 months later. The different kinetics and induction of IL-2 by different vaccines and natural exposure are described. Furthermore, both early IFN-gamma and IL-2 production independently predicted subsequent memory responses at 3 months in malaria-na?ve volunteers, but only IFN-gamma predicted memory in malaria-exposed volunteers. However, dual ELISPOT assays were also performed on malaria-exposed volunteers to identify cells producing both cytokines simultaneously. This demonstrated that double-cytokine-producing cells were highly predictive of memory. This assay may be useful in predicting vaccinations most likely to generate stable, long-term memory responses.     

Determining liver stage parasite burden by real time quantitative PCR as a method for evaluating pre-erythrocytic malaria vaccine efficacy.

The detection and quantitation of blood stage parasitaemia is typically used as a surrogate endpoint for estimating the efficacy of vaccines targeted against the hepatic stage, as well as the erythrocytic stage, of the parasite. However, this does not provide an adequate means of evaluating the efficacy of vaccines, which may be only partially effective at the liver-stage. This is a particular concern for effective evaluation of immune enhancement strategies for candidate pre-erythrocytic stage vaccines. Here, we have developed and validated a method for detecting and quantitating liver stage parasites, using the TaqMan fluorescent real-time quantitative PCR system (PE Applied Biosystems). This method uses TaqMan primers designed to the Plasmodium yoelii 18S rRNA gene and rodent GAPDH to amplify products from infected mouse liver cDNA. The technique is highly reproducible as demonstrated with plasmid controls and capable of efficiently quantitating liver-stage parasite burden following a range of sporozoite challenge doses in strains of mice, which differ in their susceptibility to sporozoite infection. We have further demonstrated the capacity of this technique to evaluate the efficacy of a range of pre-erythrocytic stage vaccines. Our data establish this quantitative real-time PCR assay to be a fast and reproducible way of accurately assessing liver stage parasite burden and vaccine efficacy in rodent malaria models.     

Neuropeptide-mediated regulation of hapten-specific IgE responses in mice II. Mechanisms of substance P-mediated isotype-specific suppression of BPO-specific IgE antibody-forming cell responses induced in vitro

Previous studies in our laboratory have shown that substance P (SP), injected into benzylpenicilloyl-keyhole limpet hemocyanin (BPO-KLH) sensitized mice at the peak of the benzylpenicilloyl (BPO)-specific IgE response, suppressed these responses in isotype-specific fashion within 48 h. These studies also showed that SP, but not neurotensin (NT), serotonin (5-HT), somatostatin (SOM) or gastrin, suppressed BPO-specific memory IgE antibody-forming cell (AFC) responses induced in vitro, also in isotype-specific fashion. To investigate the mechanisms by which SP suppressed BPO-specific IgE AFC responses were induced in vitro, these responses were induced by culturing spleen cells from BPO-KLH sensitized mice for 5 days with BPO-KLH with or without whole SP, amino terminal SP (SP 1–4: Arg-Lys-Pro-Lys), or carboxy terminal SP (SP 8–11: Phe-Gly-Leu-Met). In some experiments, the SP receptor antagonist (d-Pro², d-Phe⁷, d-Trp⁹)-SP (d-SP) was included in culture. In other experiments anti-interferon monoclonal antibody (anti-IFNγ mAb) was included in culture. Whole SP and SP 8–11, but not SP 1–4, suppressed BPO-specific IgE AFC responses induced in vitro. The suppression obtained was IgE isotype-specific and dose-dependent. Inclusion of SP receptor antagonist (d-Pro², d-Phe⁷, d-Trp⁹)-SP inhibited suppression of BPO-specific memory IgE AFC responses by SP or SP 8–11. The SP-mediated suppression of BPO-specific memory IgE responses appeared to involve interferon gamma (IFNγ).     

Novel antigen identification method for discovery of protective malaria antigens by rapid testing of DNA vaccines encoding exons from the parasite genome

We describe a novel approach for identifying target antigens for preerythrocytic malaria vaccines. Our strategy is to rapidly test hundreds of DNA vaccines encoding exons from the Plasmodium yoelii yoelii genomic sequence. In this antigen identification method, we measure reduction in parasite burden in the liver after sporozoite challenge in mice. Orthologs of protective P. y. yoelii genes can then be identified in the genomic databases of Plasmodium falciparum and Plasmodium vivax and investigated as candidate antigens for a human vaccine. A pilot study to develop the antigen identification method approach used 192 P. y. yoelii exons from genes expressed during the sporozoite stage of the life cycle. A total of 182 (94%) exons were successfully cloned into a DNA immunization vector with the Gateway cloning technology. To assess immunization strategies, mice were vaccinated with 19 of the new DNA plasmids in addition to the well-characterized protective plasmid encoding P. y. yoelii circumsporozoite protein. Single plasmid immunization by gene gun identified a novel vaccine target antigen which decreased liver parasite burden by 95% and which has orthologs in P. vivax and P. knowlesi but not P. falciparum. Intramuscular injection of DNA plasmids produced a different pattern of protective responses from those seen with gene gun immunization. Intramuscular immunization with plasmid pools could reduce liver parasite burden in mice despite the fact that none of the plasmids was protective when given individually. We conclude that high-throughput cloning of exons into DNA vaccines and their screening is feasible and can rapidly identify new malaria vaccine candidate antigens.     

Specialty Clinics for the Dermatologic Care of Solid-Organ Transplant Recipients

Background. Solid-organ transplant recipients constitute a complex patient population that experiences numerous and aggressive skin cancers. Proactive, comprehensive, ongoing, and effective dermatologic care of these patients is a necessity.
Objective. The objective of this study was to emphasize the need for organized dermatologic care for transplant recipients and to collect and present various proactive paradigms established in and designed for different practice settings to manage organ transplant recipients at high risk for skin cancer.
Methods. Information about practice setting, patient demographics, and the care model used was obtained through questionnaires sent to a selection of 12 physicians known to care for transplant recipients in various practice settings.
Results. All 12 physicians completed the questionnaire. The organized dermatologic care of transplant recipients occurs in three basic clinic settings: multidisciplinary transplant clinics, designated dermatology transplant subspecialty clinics, and integration of transplant recipient care within existing dermatology clinics.
Conclusions. Various practice settings offer both advantages and disadvantages in providing preventive and therapeutic care of organ transplant recipients at risk for skin cancer. Regardless of the clinic design used, an organized and firmly established clinic model to allow proactive and ongoing care for these patients is important for education, prevention, and early intervention.     

Expanding the natural history of nonalcoholic steatohepatitis: from cryptogenic cirrhosis to hepatocellular carcinoma

BACKGROUND & AIMS: Nonalcoholic steatohepatitis (NASH) may progress to cirrhosis; whether NASH plays also a role in the development of hepatocellular carcinoma (HCC) is unknown. METHODS: Among 641 cirrhosis-associated HCCs, we retrospectively identified 44 patients with cryptogenic cirrhosis (CC). Of these, 23 were actively followed up and were compared in a case-control study with viral- and alcohol-associated HCC. Family and personal history of diabetes, hypertension, coronary heart disease, dyslipidemia, obesity, and biochemical data were compared between groups. Iron status and presence of mutations in the HFE gene of familiar hemochromatosis were also determined. RESULTS: Family history was not different in relation to etiology. The prevalence of obesity and diabetes was significantly higher in patients with CC. Although liver function was similar, CC patients had higher glucose, cholesterol, and triglyceride plasma levels, increased parameters of insulin resistance, and lower aminotransferase levels. Iron status and prevalence of mutations in the HFE gene did not differ. Logistic regression analysis identified in sequence hypertriglyceridemia, diabetes, and normal aminotransferases as independent factors associated with HCC arising in CC. CONCLUSIONS: Features suggestive of NASH are more frequently observed in HCC arising in patients with CC than in age- and sex-matched HCC patients of well-defined viral or alcoholic etiology. HCC may represent a late complication of NASH-related cirrhosis.