Effect of ribavirin and amantadine on early hepatitis C virus RNA rebound and clearance in serum during daily high-dose interferon

The early rebound in serum HCV RNA during HCV dynamic studies with high-dose interferon may be due to de novo infection with interferon escape quasispecies. We simultaneously measured serum alanine aminotransferase (ALT) and HCV RNA at rapid intervals in chronic HCV liver disease patients during interferon therapy alone or in combination with ribavirin and amantadine. HCV RNA declined rapidly between 0 and 48 hr in all patients (phase 1). Ribavirin and amantadine significantly increased this phase 1 decline. In all four monotherapy patients with viral rebound, the increasing levels of HCV RNA were associated with a parallel increase in serum ALT, consistent with a hepatitis flare or de novo infection. By contrast, in the four monotherapy patients without viral rebound, and all eight patients receiving combination therapy, the slow progressive phase two decay was associated with declining serum ALT levels. Ribavirin or ribavirin and amantadine significantly and incrementally increased the phase two HCV RNA clearance. Dynamic sequencing in the HVR1 region in one rebound patient confirmed the potential for rapid evolutionary changes during interferon therapy. These preliminary data suggest that early viral rebound might be associated with de novo infection with interferon escape HCV variants, which in turn are attenuated by ribavirin and amantadine.     

Changes in parietal cell structure and function in HIV disease

The mechanisms underlying acid secretory failure in patients with HIV disease are unknown. We evaluated, in a series of preliminary studies, changes associated with parietal cell structure and function in early and late HIV disease, in an attempt to elucidate possible underlying mechanisms. Gastric acid and intrinsic factor secretion, vitamin B₁₂ absorption, and light and electron microscopic evaluation of gastric mucosa were evaluated in patients with early and late HIV infection (AIDS) and compared to non-HIV-infected controls. Immunolocalization of HIV-related antigens in gastric mucosa was also examined. Fasting gastric juice pH and intrinsic factor (IF) concentration in AIDS and HIV infected subjects were significantly different from controls (P=0.012 andP=0.025, respectively for pH, and 0.029 and 0.035 for IF; ANOVA LSD test). By contrast, maximal acid output (MAO) was significantly lower in AIDS, but not HIV-infected subjects (P=0.043 andP=0.322, respectively). Similarly, Schilling test phases 1 and 2 results were significantly lower in AIDS, but not HIV-infected subjects. Varying degrees of vacuolar degeneration of parietal cells were seen on light microscopy. On electron microscopy (EM), tubulovesicles were reduced and intracellular canaliculi dilated with striking loss of microvilli. Immunofluorescent staining with antibodies to gp120, gp41, p24, and p17 demonstrated positive punctate signals in the cytoplasm of gastric glands, which includes parietal cells. Immunogold EM with anti-gp120, localized predominantly to the microvilli of intracellular canaliculi in parietal cells. Abnormal secretory function of parietal cells occurs early in HIV disease, affects acid as well as intrinsic factor secretion, and is associated with morphological changes in the acid secretory apparatus.     

Proteomics for rejection diagnosis in renal transplant patients: Where are we now?

Rejection is one of the key factors that determine the long-term allograft function and survival in renal transplant patients. Reliable and timely diagnosis is important to treat rejection as early as possible. Allograft biopsies are not suitable for continuous monitoring of rejection. Thus, there is an unmet need for non-invasive methods to diagnose acute and chronic rejection. Proteomics in urine and blood samples has been explored for this purpose in 29 studies conducted since 2003. This review describes the different proteomic approaches and summarizes the results from the studies that examined proteomics for the rejection diagnoses. The potential limitations and open questions in establishing proteomic markers for rejection are discussed, including ongoing trials and future challenges to this topic.     

A novel role of the corticotrophin‐releasing hormone regulating peptide,teneurin C‐terminal associated peptide 1, on glucose uptake into the brain

Teneurin C‐terminal associated peptide (TCAP) is an ancient paracrine signalling agent that evolved via lateral gene transfer from prokaryotes into an early metazoan ancestor. Although it bears structural similarity to corticotrophin‐releasing hormone (CRH), it inhibits the in vivo actions of CRH. The TCAPs are highly expressed in neurones, where they induce rapid cytoskeletal rearrangement and are neuroprotective. Because these processes are highly energy‐dependent, this suggests that TCAP has the potential to regulate glucose uptake because glucose is the primary energy substrate in brain, and neurones require a steady supply to meet the high metabolic demands of neuronal communication. Therefore, the objective of the present study was to assess the effect of TCAP‐mediated glucose uptake in the brain and in neuronal cell models. TCAP‐mediated ¹⁸F‐deoxyglucose (FDG) uptake into brain tissue was assessed in male wild‐type Wistar rats by functional positron emission tomography. TCAP‐1 increased FDG uptake by over 40% into cortical regions of the brain, demonstrating that TCAP‐1 can significantly enhance glucose supply. Importantly, a single nanomolar injection of TCAP‐1 increased brain glucose after 3 days and decreased blood glucose after 1 week. This is corroborated by a decreased serum concentration of insulin and an increased serum concentration of glucagon. In immortalised hypothalamic neurones, TCAP‐1 increased ATP production and enhanced glucose uptake by increasing glucose transporter recruitment to the plasma membrane likely via AKT and mitogen‐activated protein kinase/ERK phosphorylation events. Taken together, these data demonstrate that TCAP‐1 increases glucose metabolism in neurones, and may represent a peptide signalling agent that regulated glucose uptake before insulin and related peptides.     

Alternative salvage regimens for relapsed/refractory classical Hodgkin's lymphoma

Objective and importance: Hodgkin's lymphoma (HL) is a well-curable disease. The treatment usually includes combined multiagent conventional chemotherapy and radiotherapy. One-fifth of the patients need repeated treatments because of relapse or primary progressive disease. Those HL patients, who cannot be cured at least with salvage therapy (including autologous haemopoietic stem cell transplantation (auto-HSCT)), have really unfavourable prognosis.

Intervention: For this heavily pretreated subset of HL patients, novel but less toxic treatment strategies should be considered. Brentuximab-vedotin (BV) is a novel targeted treatment option, which was administered after the failure of two different regimens in patients, who were ineligible for auto-HSCT or after the failure of auto-HSCT. Moreover, there are favourable data with chemotherapeutical regimens supplemented with rituximab not only in relapsed but also in newly diagnosed classical HL patients. Bendamustine, an almost forgotten 50-year-old drug, lives its renaissance in the twenty-first century, which can be administered in refractory HL as well. Combination of the ‘new’ and ‘old’ drugs might be also helpful.

Conclusion: Our data suggest that rituximab plus bendamustine (supplemented with or without BV) could be a suitable alternative bridging salvage therapy for heavily pretreated HL patients.     

Clonal expansion of immunoglobulin M+CD27+ B cells in HCV-associated mixed cryoglobulinemia

Hepatitis C virus (HCV) is associated with B-cell lymphoproliferative disorders such as mixed cryoglobulinemia (MC) and B-cell non-Hodgkin lymphoma (B-NHL). The pathogenesis of these disorders remains unclear, and it has been proposed that HCV drives the pro-liferation of B cells. Here we demonstrate that certain HCV(+)MC(+) subjects have clonal expansions of immunoglobulin M (IgM)(+)kappa(+)IgD(low/-)CD21(low)CD27(+) B cells. Using RT-PCR to amplify Ig from these singly sorted cells, we show that these predominantly rheumatoid factor-encoding V(H)1-69/J(H)4 and V(kappa)3-20 gene segment-restricted cells have low to moderate levels of somatic hypermutations. Ig sequence analysis suggests that antigen selection drives the generation of mutated clones. These findings lend further support to the notion that specific antigenic stimulation leads to B-cell proliferation in HCV MC and that chronic B-cell stimulation may set the stage for malignant transformation and the development of B-NHL. The finding that these hypermutated, marginal zone-like IgM(+)CD27(+) B cells are clonally expanded in certain subjects with MC offers insight into mechanisms of HCV-associated MC and B-cell malignancy. This study was registered at www.clinicaltrials.gov as NCT00219999.     

Acute wrist and foot drop associated with hepatitis C virus related mixed cryoglobulinemia: Rapid response to treatment with rituximab

The nature of the B-cell subsets associated with chronic hepatitis C virus related type II mixed cryoglobulinemia (HCV-MC) is unclear.We report the case of a 64-year-male with acute onset wrist drop and foot drop, secondary to HCV-MC related mononeuritis multiplex, who was treated with rituximab, an anti-CD20⁺ antibody directed against B cells. We monitored the frequency of B-cell subsets in peripheral blood before and after rituximab, and correlated B-cell subset changes with clinical response.Significant improvements in his wrist and foot drop, as well as his vasculitic rash, depression and erectile dysfunction were evident within six days of starting rituximab and have persisted several months after B-cell recovery.More than 95% of CD20⁺ B cells had disappeared from peripheral blood within 1 week, returning to baseline by week 21. CD20⁺CXCR3⁺ frequency at baseline was similar to that at week 21. CD20⁺CD5⁺, the human equivalent of B1 B cells and CD20⁺IgM⁺IgD⁺, naïve B cells were increased. By contrast, CD20⁺CD27⁺ memory cell frequency was reduced.These data suggest that CD27⁺ memory B cells, but not CD5⁺ and IgM⁺IgD⁺ B cells may play a role in the clinical manifestations of cryoglobulinemia.