Infection and glomerulonephritis

Application of nanotechnology in the treatment of glomerulonephritis: current status and future perspectives

Glomerulonephritis (GN) is the most common cause of end-stage renal failure worldwide; in most cases, it cannot be cured and can only delay the progression of the disease. At present, the main treatment methods include symptomatic therapy, immunosuppressive therapy, and renal replacement therapy. However, effective treatment of GN is hindered by issues such as steroid resistance, serious side effects, low bioavailability, and lack of precise targeting. With the widespread application of nanoparticles in medical treatment, novel methods have emerged for the treatment of kidney diseases. Targeted transportation of drugs, nucleic acids, and other substances to kidney tissues and even kidney cells through nanodrug delivery systems can reduce the systemic effects and adverse reactions of drugs and improve treatment effectiveness. The high specificity of nanoparticles enables them to bind to ion channels and block or enhance channel gating, thus improving inflammation. This review briefly introduces the characteristics of GN, describes the treatment status of GN, systematically summarizes the research achievements of nanoparticles in the treatment of primary GN, diabetic nephropathy and lupus nephritis, analyzes recent therapeutic developments, and outlines promising research directions, such as gas signaling molecule nanodrug delivery systems and ultrasmall nanoparticles. The current application of nanoparticles in GN is summarized to provide a reference for better treatment of GN in the future.

Immune complexes as culprits of immunopathology in severe COVID-19

Infection with the pandemic human coronavirus SARS-CoV-2 elicits a respiratory tract disease, termed Coronavirus disease 2019 (COVID-19). While a variable degree of disease-associated symptoms may emerge, severe COVID-19 is commonly associated with respiratory complications such as acute respiratory distress syndrome (ARDS), the necessity for mechanical ventilation or even extracorporeal membrane oxygenation (ECMO). Amongst others, disease outcome depends on age and pre-existing conditions like cardiovascular diseases, metabolic disorders but also age and biological sex. Intriguingly, increasing experimental and clinical evidence suggests that an exacerbated inflammatory response and in particular IgG immune complexes (ICs), significantly contribute to severe and prolonged COVID-19 disease progression. Vast amounts of deposited, unresolved ICs in tissue are capable to initiate an exaggerated Fc gamma receptor (FcγR) mediated signalling cascade which eventually results in common IC-associated organ diseases such as vasculitis, glomerulonephritis and arthritis, comorbidities that have been frequently reported for COVID-19. Moreover and independent of deposited ICs, very recent work identified soluble ICs (sIC) to be also present in the circulation of a majority of severely ill patients, where their systemic abundance correlated with disease severity. Thus, detection of circulating sICs in patients represents a potential marker for critical COVID-19 disease progression. Their detection early after clinical deterioration might become an indicator for the requirement of prompt anti-inflammatory treatment. Here, we review the role of ICs in COVID-19 progression, their possible origins and potential intervention strategies.

Establishment and clinical application of an assay for the activity of circulating immune complexes using human O-erythrocytes as an indicator system

OBJECTIVE

To develop a suitable clinical laboratory assay for detecting the activity of circulating immune complexes (CICs) that activate complement (ACIC).

METHODS

CICs measured in serum were initially used to activate complement, and the remaining complement was activated through sensitized human O-erythrocytes. ACIC was quantified by the degree of hemolysis. Each serum sample was tested for ten consecutive days to determine its stability. Reference ranges are suggested. ACIC was measured in both healthy individuals and patients with autoimmune diseases as well.

RESULTS

The OD values of the hemolysis degree index were inversely proportional to ACIC (r=0.986, P=0.002). A pooled serum was used to eliminate interference and optimize the experiment. The hemolysis degree (HD) was used to indicate the detection result. HD = (detection value OD/negative value OD)*100. The inter-batch results showed good stability with a CV of 6.5%. HD differences between males and females were significant (P=0.015) while the normal distribution for both genders was conformed. The HD recommended reference range for men is 56-88 while for women is 51-86. Serum HD of healthy subjects and autoimmune disease patients showed a significant difference (P=0.001). Autoimmune disease patients have higher HD which was a result of having stronger ACIC.

CONCLUSION

The ACIC assay while utilizing human O-erythrocytes as an indicator system is sensitive and accurate, and has potential in clinical applications.

Similarities and Differences between COVID-19-Associated Nephropathy and HIV-Associated Nephropathy

Kidney disease is a major complication of viral infection, which can cause both acute and chronic kidney diseases via different mechanisms such as immune-mediated injury, kidney cell injury from a direct viral infection, systemic effects, and antiviral drug-induced nephrotoxicity. HIV-associated nephropathy (HIVAN), characterized by collapsing focal segmental glomerulosclerosis (cFSGS), has been described 2 decades ago as a major complication of acquired-immunodeficiency syndrome. The pathogenesis of HIVAN has been well studied, including viral entry, host response, and genetic factors. The incidence of this disease has been dramatically dropped with current antiretroviral therapy. In the recent severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic, acute kidney injury was also found to be a major complication in patients with (coronavirus disease) COVID-19. These patients also developed glomerular disease such as cFSGS in African Americans with apolipoprotein L1 risk alleles, similar to HIVAN. Whether SARS-CoV-2 can infect kidney cells locally remains controversial, but both local infection and systemic effects are likely involved in the pathogenesis of this disease. In this review, we present a comparison of the clinical presentations, pathological findings, disease mechanisms, and potential treatments between HIVAN and COVID-19. Leveraging the knowledge in HIVAN and experimental approaches used to study HIVAN will facilitate the exploration in the pathogenesis of COVID-19-associated kidney disease and improve our management of COVID-19 patients.

Goose nephritic astrovirus infection increases autophagy, destroys intercellular junctions in renal tubular epithelial cells, and damages podocytes in the kidneys of infected goslings

Goose nephritic astrovirus (GNAstV) has recently been identified, which causes kidney swelling and visceral gout in goslings. However, the pathological changes in kidney tissue due to GNAstV infection have not yet been described. In the study, fifty goslings were orally infected with GNAstV, and fifty goslings received PBS as a control. Kidney tissue was collected at different days following infection (dpi) to assess the injury. GNAstV infection reduced body weight, increased the relative weight of the kidney, and increased serum uric acid and creatinine levels. GNAstV was found within renal epithelial cells, and the viral load in the kidney peaked at 7 dpi. Pale and swollen kidney tissue was observed in infected goslings, especially at 5 and 7 dpi. GNAstV infection caused degeneration and necrosis of renal epithelial cells, structural destruction of the brush border, glycogen deposition in the glomerular mesangium, increased fibrosis, and infiltration of inflammatory cells into the renal interstitium. Moreover, swollen mitochondria, broken mitochondrial ridges, autophagosomes, and autophagolysosomes were observed under ultrahistopathological examination. GNAstV infection increased levels of LC3B, ATG5, and Beclin 1, and decreased p62, and downregulated WT1 mRNA and upregulated desmin mRNA. At early stages, GNAstV infection decreased expression of intercellular junction-related genes, including ZO-1, occludin, claudin-10, and catenin-α2. In conclusion, GNAstV infection causes renal epithelial cell autophagy, destruction of brush border and intercellular junctions, podocyte damage, and increased fibrosis, ultimately resulting in damage to the kidney.

Heritability of glomerulonephritis: A Swedish adoption study

BACKGROUND

Glomerulonephritis clusters in families. However, infections are common inducers of glomerulonephritis and may also cluster in families. Studies of adoptees and their biological and adoptive parents may disentangle genetic from environmental causes of familial clustering. This is the first adoption study aimed to estimate the genetic contribution to the familial transmission of glomerulonephritis.

MATERIALS AND METHODS

We performed a family study for Swedish-born adoptees (born 1945-2000) and their biological and adoptive parents. The Swedish Multi-Generation Register was linked to the Hospital Inpatient Register for the period 1964-2012 and the Hospital Outpatient Register for 2001-2012. Odds ratio (OR) for glomerulonephritis was determined for adoptees with a biological parent with glomerulonephritis compared with adoptees without an affected biological parent. Similarly, the OR for glomerulonephritis was also determined in adoptees with an affected adoptive parent compared with adoptees without an affected adoptive parent. Heritability was estimated to be twice the observed tetrachoric correlation among adoptees and biological parents, under the assumption that only additive genetic factors contribute to the similarity between biological parents and adoptees.

RESULTS

The OR for glomerulonephritis was 4.08 in adoptees (95% confidence interval [CI] 1.79-9.27, P-value = 0.001) of biological parents diagnosed with glomerulonephritis. The OR for glomerulonephritis was 1.67 in adoptees (95% CI 0.53-5.26, P-value = 0.380) of adoptive parents diagnosed with glomerulonephritis. The heritability was 48%.

CONCLUSION

Family history of glomerulonephritis in a biological parent is a risk factor for glomerulonephritis. The present study indicates that genetic factors play an important role in the aetiology of glomerulonephritis.

Renal function in HIV/HBV co-infected and HBV mono-infected patients on a long-term treatment with tenofovir in real life setting

The human immunodeficiency virus (HIV)/hepatitis B virus (HBV) co-infection is likely to be associated with an increased risk of kidney disease, due to the additional factors that may affect renal function in the HIV population. We aimed to evaluate renal toxicity in HIV/HBV and HBV mono-infected patients on long-term therapy with tenofovir (TDF) and to explore the association of polymorphisms in ATP-binding cassette (ABCC)2, ABCC4, ABCC10 with the development of renal dysfunction. From September 2006 to November 2014, 44 HIV/HBV co-infected and 34 HBV mono-infected patients were commenced on TDF. Data of renal safety were retrospectively collected and analyzed. ABCC2, ABCC4 and ABCC10 genotypes were identified by real-time PCR. Over 60 months of observation, there was a significant increase in mean creatinine levels from baseline (P<.01) that was not significantly different between the two study groups. Moreover, a significant decline in estimated glomerular filtration rate (eGFR) was observed from baseline (P<.01), and it was significantly greater in HBV mono-infected than co-infected patients (P=.03). The distribution of ABCC2, ABCC4 and ABCC10 genotypes among a subgroup of 34 patients did not show significant association with eGFR decline <90 mL/min per 1.73 m² . Although our findings showed a statistically significant decrease in eGFR with long-term use of TDF, its clinical impact seems to be modest. The role of genetic factors to identify patients at greater risk for developing tenofovir-induced renal toxicity needs to be further investigated.

NEPHROPATHIES IN THE EUROPEAN CAPTIVE CHEETAH (ACINONYX JUBATUS) POPULATION

According to previous studies in captive cheetah ( Acinonyx jubatus ) populations, one of the most threatening diseases besides amyloidosis, myelopathy, veno occlusive disease, and gastritis, is renal failure. Contrary to captive cheetahs in North America and South Africa, morphological data concerning renal lesions in the cheetah European Endangered Species Program (EEP) are lacking. This study details the histological characterization as well as immunohistochemical and morphometrical analysis of nephropathies in 35 captive cheetahs from the EEP, which were necropsied between 1985 and 2003. Examination of paraffin- and glycolmethacrylate-methylmethacrylate (GMA-MMA) embedded kidney samples by light microscopy revealed glomerulonephritis in 91%, with a high prevalence for glomerulosclerosis and glomerulonephritis with the histologic pattern of membranous glomerulonephritis (77%). Besides these predominating glomerulopathies, a wide range of other renal lesions, like acute tubular necrosis, interstitial nephritis, calcinosis, and amyloidosis, were present. Pathological expression of collagen type IV, complement C3, fibronectin, and IgG was demonstrated in the glomeruli of the cheetah kidneys with the use of the avidin-biotin complex method. Morphometrical analysis was performed on GMA-MMA embedded kidney samples to obtain glomerulosclerosis index and glomerulosclerosis incidence.

IL-10 mediates plasmacytosis-associated immunodeficiency by inhibiting complement-mediated neutrophil migration

BACKGROUND

Plasmacytosis (ie, an expansion of plasma cell populations to much greater than the homeostatic level) occurs in the context of various immune disorders and plasma cell neoplasia. This condition is often associated with immunodeficiency that causes increased susceptibility to severe infections. Yet a causative link between plasmacytosis and immunodeficiency has not been established.

OBJECTIVE

Because recent studies have identified plasma cells as a relevant source of the immunosuppressive cytokine IL-10, we sought to investigate the role of IL-10 during conditions of polyclonal and neoplastic plasmacytosis for the regulation of immunity and its effect on inflammation and immunodeficiency.

METHODS

We used flow cytometry, IL-10 reporter (Vert-X) and B cell-specific IL-10 knockout mice, migration assays, and antibody-mediated IL-10 receptor blockade to study plasmacytosis-associated IL-10 expression and its effect on inflammation and Streptococcus pneumoniae infection in mice. ELISA was used to quantify IL-10 levels in patients with myeloma.

RESULTS

IL-10 production was a common feature of normal and neoplastic plasma cells in mice, and IL-10 levels increased with myeloma progression in patients. IL-10 directly inhibited neutrophil migration toward the anaphylatoxin C5a and suppressed neutrophil-dependent inflammation in a murine model of autoimmune disease. MOPC.315.BM murine myeloma leads to an increased incidence of bacterial infection in the airways, which was reversed after IL-10 receptor blockade.

CONCLUSION

We provide evidence that plasmacytosis-associated overexpression of IL-10 inhibits neutrophil migration and neutrophil-mediated inflammation but also promotes immunodeficiency.

Characteristics of Circulating Immune Complexes in HIV-Infected Patients with Different Viral Load

Serum concentration of antiviral antibodies was measured in HIV-infected patients with different viral load. It was found that higher concentrations of HIV-antigens correspond to higher titer of antiviral antibodies. Circulating immune complexes were isolated from patients' serum to estimate their size and immunoglobulin composition. High levels of small IgG- and IgM-containing complexes were identified in HIV-infected patients. In patients receiving antiretroviral treatment, the content of these complexes was significantly lower than in patients with high HIV load. This attests to positive role of specific therapy in preventing immune complex-associated pathology in HIV patients.

Midkine in nephrogenesis, hypertension and kidney diseases

Midkine (MK; K; gene abbreviation, Mdk: mus musculus, MDK: homo sapiens) is a multifunctional heparin-binding growth factor that regulates cell growth, survival and migration as well as anti-apoptotic activity in nephrogenesis and development. Proximal tubular epithelial cells are the main sites of MK expression in the kidneys. The pathophysiological roles of MK are diverse, ranging from the development of acute kidney injury (AKI) to the progression of chronic kidney disease, often accompanied by hypertension, renal ischaemia and diabetic nephropathy. The obvious hypertension that develops in Mdk(+/+) mouse models of renal ablation compared with Mdk(-/-) mice eventually leads to progressive renal failure, such as glomerular sclerosis and tubulointerstitial damage associated with elevated plasma angiotensin (Ang) II levels. MK is also induced in the lung endothelium by oxidative stress and subsequently up-regulated by ACE, which hydrolyzes Ang II to induce further oxidative stress, thus accelerating MK generation; this leads to a vicious cycle of positive feedback in the MK-Ang II pathway. Kidney-lung interactions involving positive feedback between the renin-angiotensin system and MK might partly account for the pathogenesis of hypertension and kidney damage. MK is also involved in the pathogenesis of AKI and diabetic nephropathy through the recruitment of inflammatory cells. In contrast, MK plays a protective role against crescentic glomerulonephritis, by down-regulating plasminogen activator inhibitor-1. These diverse actions of MK might open up new avenues for targeted approaches to treating hypertension and various renal diseases.

LINKED ARTICLES

This article is part of a themed section on Midkine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-4.

Increased survival in B-cell-deficient mice during experimental cerebral malaria suggests a role for circulating immune complexes

The pathogenesis of malaria, an insect-borne disease that takes millions of lives every year, is still not fully understood. Complement receptor 1 (CR1) has been described as a receptor for Plasmodium falciparum, which causes cerebral malaria in humans. We investigated the role of CR1 in an experimental model of cerebral malaria. Transgenic mice expressing human CR1 (hCR1(+)) on erythrocytes were infected with Plasmodium berghei ANKA and developed cerebral malaria. No difference in survival was observed in hCR1(+) mice compared to wild-type mice following infection with P. berghei ANKA; however, hCR1 detection was significantly diminished on erythrocytes between days 7 and 10 postinfection. hCR1 levels returned to baseline by day 17 postinfection in surviving animals. Immunoblot assays revealed that total erythrocyte hCR1 levels were diminished, confirming that immune complexes in association with erythrocyte hCR1 were likely removed from erythrocytes in vivo by clearance following immune adherence. Decreases in hCR1 were completely dependent on C3 expression, as mice treated with cobra venom factor (which consumes and depletes C3) retained hCR1 on erythrocytes during C3 depletion through day 7; erythrocyte hCR1 decreases were observed only when C3 levels recovered on day 9. B-cell-deficient mice exhibit a marked increase in survival following infection with P. berghei ANKA, which suggests that immune complexes play a central role in the pathogenesis of experimental cerebral malaria. Together, our findings highlight the importance of complement and immune complexes in experimental cerebral malaria. IMPORTANCE Cerebral malaria is a deadly complication of infection with Plasmodium falciparum. Despite its high prevalence, relatively little is understood about its pathogenesis. We have determined that immune complexes are generated and deposited on erythrocytes specifically expressing human complement receptor 1 in a mouse model of cerebral malaria. We also provide evidence demonstrating the importance of immunoglobulins in the pathogenesis of cerebral malaria in mice. These findings may have important implications in human cerebral malaria.

Acute tubulointerstitial nephritis complicating Legionnaires' disease: a case report

Introduction

Legionnaires' disease is recognized as a multi-systemic illness. Afflicted patients may have pulmonary, renal, gastrointestinal tract and central nervous system complications. However, renal insufficiency is uncommon. The spectrum of renal involvement may range from a mild and transient elevation of serum creatinine levels to anuric renal failure requiring dialysis and may be linked to several causes. In our present case report, we would like to draw attention to the importance of the pathological documentation of acute renal failure by reporting a case of a patient with acute tubulointerstitial nephritis complicating Legionnaires' disease.

Case presentation

A 55-year-old Caucasian man was admitted to our hospital for community-acquired pneumonia complicated by acute renal failure. Legionella pneumophila serogroup type 1 was diagnosed. Although the patient's respiratory illness responded to intravenous erythromycin and ofloxacin therapy, his renal failure worsened, he became anuric, and hemodialysis was started. A renal biopsy was performed, which revealed severe tubulointerstitial nephritis. After initiation of steroid therapy, his renal function improved dramatically.

Conclusions

This case highlights the importance of kidney biopsies in cases where acute renal failure is a complicating factor in Legionnaires' disease. If the presence of acute tubulointerstitial nephritis can be confirmed, it will likely respond favorably to steroidal treatment and thus irreversible renal damage and chronic renal failure will be avoided.

Post-infection immunocomplex glomerulonephritis and Legionnaires' disease in a patient with adult Still's disease during treatment with interleukin 1 receptor antagonist anakinra: a case report

Introduction

Legionellosis is a systemic disease that primarily affects the lungs. However, dysfunction in many organ systems, including the kidneys, has also been described. There are only a few reported cases of renal dysfunction in patients with legionellosis.

Case presentation

A 27-year-old Caucasian woman with known adult Still's disease was admitted to our hospital for community-acquired pneumonia, due to Legionella infection, with acute renal failure. Although her respiratory symptoms responded well to antibiotic treatment, her renal function worsened, with severe proteinuria and edema. A renal biopsy showed extracapillary and endocapillary proliferative glomerulonephritis with accompanying chronic and acute interstitial nephritis. This was consistent with a post-infection immunocomplex glomerulonephritis. After initiation of steroid therapy, her renal function improved. Additionally, therapy with diuretics and an angiotensin-converting enzyme inhibitor was initiated because of persistent proteinuria. Under this treatment regimen, her severe edema and proteinuria disappeared.

Conclusion

To the best of our knowledge, there is only a handful of reported cases of post-infection glomerulonephritis with a nephrotic syndrome in a patient with legionellosis. Our findings suggest that, in patients with Legionnaires' disease with renal failure, post-infection immunocomplex glomerulonephritis should be considered and steroid therapy may be an effective modality to treat the renal complication.

A causative link between periodontal disease and glomerulonephritis: a preliminary study

Background:

Periodontal disease has been associated with a number of systemic diseases. A high prevalence of periodontitis among individuals with chronic kidney diseases and end-stage renal disease has been reported. However, no association between periodontal diseases and glomerulonephritis has previously been investigated.

Objective:

The aim of this study was to assess the severity and possible role of periodontitis in a group of patients with unknown primary glomerulonephritis.

Methods:

Ten patients with unknown primary glomerulonephritis, and who had a renal biopsy with stable renal function and serum creatinine <1.6 mg/dL, were recruited. Severity of the periodontal disease was clinically measured with plaque index (PI), gingival index (GI), and periodontal pocket depth (PD). The subjects received appropriate dental treatments where indicated. The patients were also put on angiotensin-converting enzyme inhibitor or angiotensin receptor blockers for controlling blood pressure and proteinuria. Six months following appropriate periodontal treatment, renal function, degree of proteinuria, and level of C-reactive protein (CRP) were measured in each individual.

Results:

The median age of the patients was 30 (15.8) years. The median urine protein excretion was lower following the periodontal therapy (P=008). Prior to the dental and/or periodontal therapies, the median PI, PD, and GI were 57.5%, 4.3, and 1.1, respectively. The majority of the patients had advanced periodontal disease. In four patients, +2/+3 CRP turned negative after periodontal treatment.

Conclusions:

The present study revealed that a causative link might exist between periodontal disease and glomerulonephritis.

Growth factor Midkine is involved in the pathogenesis of renal injury induced by protein overload containing endotoxin

BACKGROUND

Growth factor Midkine (MK), which expresses on endothelial cells and renal proximal tubules, has been implicated in inflammation-related kidney diseases such as ischemic reperfusion-induced tubulointerstitial injury and diabetic nephropathy. The biological actions of MK are elicited through its chemotactic activity and chemokine-driven inflammatory pathway. Post-infectious glomerulonephritis is caused by the deposition of immune complexes into glomeruli by infiltrating a number of inflammatory cells. Therefore, we investigated whether MK might be involved in the pathogenesis of acute glomerulonephritis.

METHODS

We induced endocapillary proliferative glomerulonephritis in 129/SV mice using intraperitoneal injections of a large amount of protein.

RESULTS

In contrast to mice deficient in MK (Mdk (-/-)), Mdk (+/+) mice induced by protein overload demonstrated more diffuse cellular proliferation in the mesangial areas and capillary lumens, eventually leading to glomerular damage and tubulointerstitial injury. This pathological observation could be attributable to neutrophil infiltration through the chemotaxis and stimulation of the MK-macrophage inflammatory protein (MIP)-2 pathway, but appeared to be due to the MK-related immunoglobulin (Ig)G deposition and C3 activation. These findings are often seen in infectious-related glomerular injury. Furthermore, the profile of MK expression was strongly consistent with that of glomerular damage and tubulointersititial injury.

CONCLUSION

This study might provide a new insight into understanding the deleterious role of MK in endocapillary proliferative glomerulonephritis induced by protein overload.

Molecular bases of immune complex pathology

The binding of antigens with antibodies forms immune complexes in the body. Usually these complexes are eliminated by the system of mononuclear phagocytes without development of pathological changes. This review highlights principal mechanisms responsible for safe removal of immune complexes in primates and humans. Special attention is given to diseases known as "immune complex diseases", when antigen-antibody complexes induce inflammatory reactions. The review considers key experimental works that significantly contributed to current knowledge of etiology and pathogenesis of type III hypersensitivity. Some factors of the development of immune complex syndrome such as level of humoral immune response to antigen, isotype and affinity of forming antibodies, the amount of immune complexes, and the consequences of their interaction with the complement system and Fc-receptors are analyzed based on the molecular mechanisms involved. The review contains a retrospective analysis of the most significant scientific achievements in immune complex pathology investigation within the last 100 years.

Reduced glomerular filtration rate but sustained virologic response in HIV/hepatitis B co-infected individuals on long-term tenofovir

Reports have described a decrease in glomerular filtration rate (eGFR) associated with tenofovir disoproxil fumarate (TDF) use in HIV positive individuals. However, no study has examined renal function over a prolonged period in HIV/hepatitis B virus (HBV) co-infected patients. We assessed the long-term durability and toxicity of TDF in a cohort of 39 e antigen (eAg) positive co-infected patients commenced on TDF 245 mg daily either in addition to or as part of standard antiretroviral therapy. Immunological and virological parameters were followed to 260 weeks, with the median follow-up period being 251 weeks (range 69-290 weeks). eGFR was calculated using the Modification in Diet in Renal Disease equation. On treatment at 260 weeks, 88% (14/16) had HIV viral load <50 copies/mL, median CD4 count rose from 318 to 532 cells/mm(3), median alanine aminotransferase (ALT) fell from 61 IU/L to 42 IU/L, with 35% (7/20) having a normal ALT, median HBV DNA fell from 69 x 10(6) copies/mL to 500 copies/mL, with 75% (12/16) having an undetectable HBV DNA level and 55% (6/11) becoming eAg negative. Of those with detectable HBV DNA, none had TDF resistance mutations. The eGFR declined by 22.19 mL/min/1.73 mm(2) from baseline (P = 0.023) over this period, which was unaffected by protease inhibitor use, baseline CD4 count, ALT or HBV DNA level. Three patients discontinued TDF therapy due to renal dysfunction. In conclusion, TDF has sustained efficacy but is associated with a significant decline in eGFR. Further larger studies are required to clarify this observation.

Pharmacotherapy of chronic viral hepatitis and hepatocellular carcinoma

BACKGROUND

Hepatitis B virus (HBV) is a major etiologic agent of chronic liver disease (CLD) and hepatocellular carcinoma. Drugs have been developed and shown to be effective against HBV replication. These treatments are often associated with the resolution of CLD. However, they are too expensive, not well tolerated, and result in the development of resistance when given as mono or salvage therapies. In addition, most of these drugs target only the virus polymerase.

OBJECTIVE

To revitalize the field, drugs with other targets and combination therapies need to be developed.

METHODS

Major advances in HBV and liver cancer drug development over the past decade, focusing on Phase III trials and FDA-approved compounds, are presented.

RESULTS/DISCUSSION

A number of potent nucleoside/nucleotide analogs are now available for treatment, but for the long-term management of CLD, the development of combination therapies will probably be required. Development of compounds with new virus targets will enhance the utility of combination therapies. Development of compounds to host targets altered prior to or after the development of liver cancer, as demonstrated by sorafenib, need to be developed. The goal is to devise drug cocktails that will yield sustained virus responses and halt disease progression and tumor development.

Composition of inflammatory infiltrate and its correlation with HBV/HCV antigen expression

AIM: To study the composition of liver inflammatory infiltrate in biopsy material from patients chronically infected with hepatotropic viruses and to evaluate the correlation of inflammatory infiltrate with hepatitis B virus (HBV) and hepatitis C virus (HCV) viral antigen expression in chronic B and C hepatitis.

METHODS: The phenotype of inflammatory cells was evaluated by the EnVision system, using a panel of monoclonal antibodies. HBV and HCV antigens were detected with the use of monoclonal anti-HBs, polyclonal anti-HBc and anti-HCV antibodies, respectively.

RESULTS: The cellular composition of liver inflammatory infiltrate was similar in the patients with B and C hepatitis: ~50%-60% of cells were T helper lymphocytes. Approximately 25% were T cytotoxic lymphocytes; B lymphocytes comprised 15% of inflammatory infiltrate; other cells, including NK, totalled 10%. Expression of HLA antigens paralleled inflammatory activity. Portal lymphadenoplasia was found more often in hepatitis C (54.5%) than in hepatitis B (30.6%). Expression of HBcAg was found more often in chronic B hepatitis of moderate or severe activity. Overall inflammatory activity in HBV-infected cases did not correlate with the intensity of HBsAg expression in hepatocytes. Inflammatory infiltrates accompanied the focal expression of HCV antigens. A direct correlation between antigen expression and inflammatory reaction in situ was noted more often in hepatitis C than B.

CONCLUSION: Irrespective of the etiology and activity of hepatitis, components of the inflammatory infiltrate in liver were similar. Overall inflammatory activity did not correlate with the expression of HBsAg and HCVAg; HBcAg expression, however, accompanied chronic hepatitis B of moderate and severe activity.