mTOR signaling pathway regulates the IL-12/IL-10 axis in Leishmania donovani infection.

Leishmania-induced interleukin-12 (IL-12) expression is negatively regulated by the phosphatidylinositol 3-kinase (PI3K) and extracellular signal regulated kinase (ERK) 1/2 pathways in human monocyte derived macrophages (MDMs). To extend these studies, we examined the pathways downstream from PI3K in L. donovani-induced reciprocal regulation of IL-12/IL-10 axis in THP-1-derived macrophages. We show for the first time that in THP-1-derived macrophages and human monocytes, mTOR inhibition by rapamycin reversed L. donovani-induced IL-12 and IL-10 modulation. L. donovani-induced phosphorylation of P70S6K, a correlate of mTOR activity, in TLR-stimulated THP-1 derived macrophages. This increase in P70S6K phosphorylation was completely blocked by rapamycin (mTOR inhibitor) and partially by wortmannin (PI3K inhibitor). These observations suggest that a PI3K independent pathway is operative in the modulation of IL-12 and IL-10. Blocking of TLR2 significantly attenuated IL-10 induced by the parasite, but did not affect IL-12 production. Thus, our data suggests that intracellular network of PI3K and mTOR pathway control IL-12/IL-10 modulation by L. donovani. mTOR inhibitors may be attractive molecules to reverse this modulation and may result in control of disease.

Upregulation of HLA-G in JEG-3 cells by dexamethasone and hydrocortisone.

BACKGROUND: Various reports suggest that HLA-G molecule plays an important role in feto-maternal interface, protecting the allogenic fetus from maternal immune attack. It is shown that steroid hormones may upregulate the HLA-G gene expression. In the present study, we have made an attempt to upregulate the HLA-G gene expression in a HLA-G(+ve) cell line (JEG-3) by using two glucocorticoids drugs, i.e., dexamethasone and hydrocortisone. METHODS: Choriocarcinoma JEG-3 (HLA-G(+ve)), JAR (HLA-G(-ve)) and erythroleukemia K-562 (HLA-G(-ve)) cell lines were obtained from American Type Culture Collection. These cell lines were treated with glucocorticoids (dexamethasone and hydrocortisone). HLA-G gene transcription was determined by standard and real-time RT-PCR analysis, and protein expression was evaluated by both flow cytometry and Western blotting. RESULTS: Dose-dependent increase in HLA-G mRNA and protein expression was observed in HLA-G(+ve) JEG-3 cells, while no expression was recorded in JAR and K-562 (HLA-G(-ve)) cell lines. CONCLUSION: We were able to upregulate HLA-G expression only in HLA-G(+ve) cell line. On the basis of our results, we hypothesize that the HLA-G gene expression can be upregulated only when the cell lines/cells have the basal expression and not in the cells that totally lack its expression. We have further hypothesized that these drugs may be used only in those women with recurrent miscarriages who show minimum basal expression level of HLA-G.

Evidence of hepatitis E virus exposure among seronegative healthy residents of an endemic area.

OBJECTIVE: Hepatitis E virus (HEV) infection is endemic in the Indian subcontinent. Detection of serum anti-HEV IgG has traditionally been used to determine prior exposure to this virus. We studied HEV-specific recall immune responses in healthy subjects with and without detectable anti-HEV IgG. METHODS: Memory B and T cells specific for HEV recombinant proteins pORF2 and pORF3 were estimated among healthy subjects residing in an HEV-endemic region using enzyme-linked immunospot (ELISPOT) assays. RESULTS: Anti-HEV IgG-negative and anti-HEV IgG-positive healthy subjects had a similar median (range) number of IgG-secreting memory B cells specific for HEV pORF2 [percent of total IgG-producing cells: 0.39 (0-13.63) vs. 0.83 (0-12.78)] and HEV pORF3 [0.33 (0.05-12.35) vs. 1.01 (0.08-9.48)], and of IFN-γ-secreting memory T cells specific for HEV pORF2 [per one million PBMCs: 16 (0-220) vs. 36.5 (0-474)] and HEV pORF3 [166 (0-957) vs. 70.5 (0-533)]. Eight healthy volunteers residing in the USA and studied as controls lacked detectable T cells specific for HEV pORF2. CONCLUSION: ELISPOT assays may detect evidence of prior HEV infection in persons residing in areas endemic for this infection and lacking detectable anti-HEV IgG. Seroepidemiological studies that use the serum anti-HEV IgG test may underestimate the frequency of exposure to HEV.

Adaptive immune responses during acute uncomplicated and fulminant hepatitis E.

BACKGROUND AND AIM: Hepatitis E virus (HEV) infection is endemic in several developing countries. Clinical manifestations of this infection vary widely from asymptomatic infection to uncomplicated acute viral hepatitis and fulminant hepatic failure. The pathogenesis of this disease and the reason of varying disease severity remain unknown. In viral infections, tissue injury can be caused either by virus itself or by host immune responses directed against infected cells. We therefore studied adaptive immune responses to HEV antigens in patients with hepatitis E of varying disease severity and healthy controls. METHODS: Cytokine secreting CD4+ T cells and antibody-producing B cells specific for HEV were enumerated through intracellular cytokine staining and enzyme-linked immunosorbent spot assay, respectively. RESULTS: Patients with fulminant hepatitis E had a less marked expansion of HEV-specific interferon-γ or tumor necrosis factor-a secreting CD4+ T cells than patients with uncomplicated hepatitis E and healthy controls. These patients also had fewer CD4+ T cells that produce γ-interferon or tumor necrosis factor-a upon in vitro polyclonal stimulation. In addition, patients with fulminant disease had a more marked expansion of B cells that can secrete immunoglobulin G anti-HEV than patients with uncomplicated infection and control patients. CONCLUSION: These findings suggest that less-marked antiviral cellular immune responses and heightened antiviral humoral responses are associated with a more severe disease during HEV infection.

Association of tumor necrosis factor alpha and IL-10 promoter polymorphisms with rheumatoid arthritis in North Indian population.

Rheumatoid arthritis is a chronic autoimmune disorder associated with altered expression of pro- and anti-inflammatory cytokines in the affected tissues. The aim of this study was to investigate the association between promoter polymorphisms of TNFalpha and IL-10 gene with susceptibility, age of disease onset and disease severity in North Indian patients with rheumatoid arthritis (RA). SNPs at position -308 and -863 of TNF gene and -819/-592 and -1082 position of IL-10 gene were determined in 222 patients and 208 healthy controls using RFLP or ARMS method. Polymorphism TNF -308A was less prevalent among the patients (1.7%) than controls (4.9%; p = 0.01, OR: 0.32, 95% CI: 0.13-0.76). Among female patients, IL-10 -592A allele associated with higher baseline disease activity scores (5.77 +/- 1.99) than -592C (5.57 +/- 1.19; p = 0.04). Female patients carrying allele A of TNFalpha -863 had earlier age of onset of RA (33.99 +/- 9.6 years) than those with allele C (36.15 +/- 11.21 years; p = 0.043). In conclusion, allele A at TNFalpha -308 locus provides protection against RA in North Indian population while another TNF allele A at -863 position had weak association with earlier onset of disease in female patients. On the other hand promoter polymorphisms of IL-10 did not affect susceptibility but polymorphism at -819/-592A was associated with higher disease activity scores at baseline.

Effect of lead exposure on lymphocyte subsets and activation markers.

Lead is a common environmental pollutant which has adverse effects on the immune system. We studied frequency of peripheral blood populations of CD4, CD8, and CD56 expressing cells and presence of activation marker (CD25) and CD45 isoforms by flow cytometry. Among 59 lead-exposed individuals (26 three-wheeler drivers, 33 battery workers) and 21 healthy controls, blood lead levels were 6.7 +/- 4.5 microg/dL, 132 +/- 103 microg/dL, and 4.5 +/- 2.0 microg/dL, respectively. The percentage of CD4(+) cells was significantly lower (P < 0.001) and of CD45RA(+) cells higher (P < 0.05) in both lead-exposed groups as compared to controls. There was a significant negative correlation between the CD4(+) cell percentage and blood lead levels and length of exposure. Our data highlight the adverse effect of lead on immune cells which may have serious consequences for those with chronic exposure to lead.

Epidemiology of hepatitis E: current status.

Hepatitis E, caused by infection with hepatitis E virus (HEV), is a common cause of acute hepatitis in areas with poor sanitation. The virus has four genotypes with one serotype: genotypes 1 and 2 exclusively infect humans, whereas genotypes 3 and 4 also infect other animals, particularly pigs. In endemic areas, both large outbreaks of acute hepatitis as well as sporadic cases occur frequently. These cases are usually due to genotype 1 or 2 HEV and are predominantly caused by fecal-oral transmission, usually through contamination of drinking water; contaminated food, materno-fetal (vertical spread) and parenteral routes are less common modes of infection. The acute hepatitis caused by this virus has the highest attack rates in young adults and the disease is particularly severe among pregnant women. HEV superinfection can occur among persons with pre-existing chronic liver disease. In non-endemic regions, locally acquired disease was believed to be extremely uncommon. However, in recent years, an increasing number of cases, due mostly due to genotype 3 or 4 HEV, have been recognized. These are more often elderly men who have other coexisting illnesses, and appear to be related to zoonotic transmission from pigs, wild boars and deer, either food-borne or otherwise. Also, chronic infection with genotype 3 HEV has been reported among immunosuppressed persons in these regions. A subunit vaccine has been shown to be effective in preventing clinical disease, but is not yet commercially available. Our understanding of hepatitis E epidemiology has undergone major changes in recent years, and the future may hold even more surprises.

Leishmania donovani infection down-regulates TLR2-stimulated IL-12p40 and activates IL-10 in cells of macrophage/monocytic lineage by modulating MAPK pathways through a contact-dependent mechanism.

The failure of Leishmania, an intracellular pathogen, to stimulate a pro-inflammatory response following entry into macrophages has been well reported. This occurs in spite of the fact that ligands for the toll-like receptors (TLR) have been recently shown on the parasite surface and their role in disease protection well documented. The outcome of infection in leishmaniasis is determined by the Th1 versus Th2 nature of the effector response and the generation of IL-12 and IL-10 by the infected macrophages is important for this decision. We evaluated the effect of L. donovani infection of monocytes (cell line THP-1, and monocytes derived from human peripheral blood) on Pam3cys (TLR2 ligand) and lipopolysaccharide (TLR4 ligand) stimulated production of IL-12p40 and IL-10. L. donovani infection caused suppression of TLR2 and TLR4-stimulated IL-12p40, with an increase in IL-10 production. Parasites also modulated the TLR2-stimulated mitogen-activated protein kinase (MAPK) pathway by suppressing MAPK P(38) phosphorylation and activating extracellular regulated kinase (ERK)1/2 phosphorylation. These effects could be reversed either by using a MAPK P(38) activator, anisomycin, or ERK1/2 inhibitor, U0126. L. donovani caused modulation of TLR2-stimulated MAPK pathways in a contact-dependent mechanism. In addition parasite structural integrity but not viability was required for suppression of TLR2-stimulated IL-12p40 and activation of IL-10. These observations suggest that L. donovani has evolved survival strategies that subvert the pro-inflammatory response generated through TLRs.

Presence of antibodies to SSB/La is associated with decreased phagocytic efficiency of neutrophils in patients with systemic lupus erythematosus.

SSB/La antigen, expressed on surface of polymorphonuclear neutrophils (PMN), is one of the cognate antigens recognized by antineutrophil antibodies. The present study was aimed to assess PMNs in systemic lupus erythematosus (SLE) patients for their phagocytic efficiency and its correlation with history of infections and presence of anti-SSB/La antibodies and their capacity to produce interleukin (IL)-12 in response to lipopolysaccharide (LPS) with or without interferon gamma (IFN-gamma). Fifty patients with SLE, fulfilling American College of Rheumatology criteria of diagnosis, and 20 healthy controls were enrolled for the study. Phagocytic efficiency was evaluated by flow cytometry, using flourescein isothiocyanate (FITC)-labeled Escherichia coli, and expressed as mean channel fluorescence (MFI). PMNs were stimulated with LPS or LPS + IFN-gamma for 18 h, IL-12p40 was estimated in supernatants by enzyme-linked immunosorbent assay, and anti-SSB/La antibodies were detected in serum by Western blot. The mean MFI values were significantly lower in patients with SLE than controls (P < 0.0001), and among patients, it was lower in patients with history of infection than in those without (P < 0.005). Anti-SSB/La positivity was also associated with lower MFI (P < 0.005) and higher frequency among patients with history of infective episodes (P < 0.05). LPS- and LPS + IFN-gamma-stimulated IL-12 levels were lower among SLE patients than in controls. However, there was no difference in the levels of IL-12 between patients with and without history of infection. These data suggest that the autoantibodies to SSB/La may modulate PMN function in SLE.

Cellular immune responses in acute hepatitis E virus infection to the viral open reading frame 2 protein.

Hepatitis E virus (HEV) causes acute viral hepatitis and is endemic in the developing world. Few data are available on cellular immune responses in HEV infection. Using flow cytometry, we studied the frequencies of peripheral blood CD4(+) /CD8(+) T cells secreting interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-4 in 21 patients with acute hepatitis E and 18 healthy controls, after stimulation with the HEV capsid (ORF2) protein. Cytokine levels in serum specimens and culture supernatants of ORF2-stimulated peripheral blood mononuclear cells (PBMCs) were estimated in enzyme-linked immunosorbent assays. In addition, cytokine mRNA transcripts were measured in PBMCs by reverse transcription-polymerase chain reaction. In patients with acute hepatitis E, although the total CD4(+) population was expanded, the proportions of CD4(+)/CD69(+) and CD8(+) /CD69(+) cells producing IFN-gamma, TNF-alpha, and IL-4 in response to HEV ORF2 stimulation were unchanged. However, IFN-gamma levels in the supernatants and IFN-gamma mRNA transcripts in cells were elevated in ORF2-stimulated PBMCs in acute hepatitis E; levels of IL-2 or TNF-alpha were unchanged. Our findings suggest that CD4(+) IFN-gamma-secreting cells, which do not belong either to the helper T cell type 1 or type 2 phenotype, as is the case with natural killer T cells, may be involved in the pathogenesis of hepatitis E. Further, the limited immune reactivity we detected in peripheral blood cells may be related to the sequestration of immune events to the intrahepatic compartment, which is the major disease site.

Immune response to leishmania: paradox rather than paradigm.

The leishmaniases are a group of diseases caused by protozoan parasites of the genus Leishmania. Various Leishmania species can cause human infection, producing a spectrum of clinical manifestations. It is estimated that 350 million people are at risk, with a global yearly incidence of 1-1.5 million for cutaneous and 500,000 for visceral leishmaniasis (VL). VL is a major cause of morbidity and mortality in East Africa and the Indian subcontinent. Coinfection with HIV enhances the risk of the disease. The only control measure currently available in India is case detection and treatment with antimonial drugs, which are expensive, not always available and cannot be self-administered. Newer drugs like oral miltefosine have not become widely available. Vector and reservoir control is difficult due to the elusive nature of the vector and the diversity of the animal reservoir. A detailed knowledge of immune response to the parasite would help in designing prophylactic and therapeutic strategies against this infection.

Antinuclear antibodies by indirect immunofluorescence : optimum screening dilution for diagnosis of systemic lupus erythematosus.

BACKGROUND & OBJECTIVES: Antinuclear antibodies (ANA) are serological hallmark of systemic lupus erythematosus (SLE). Conventionally, the test is carried out on human epithelial cells (HEp2) by indirect immunofluorescence (IIF) technique. Since culturing and maintaining HEp2 cells in the laboratory are labour intensive, in-house assays have given way to kits manufactured by commercial companies. The reference screening dilutions provided by the manufacturers are based on different ethnic population than ours. Therefore, it becomes mandatory for every laboratory to have its own screening dilutions for the local population that distinguishes best between healthy and diseased state. As, there is paucity of such data, we aimed to define the optimum screening dilution that distinguishes the patient with SLE from healthy individuals. METHODS: Sera of patients fulfilling ACR criteria for diagnosis of SLE, idiopathic inflammatory polymyositis/dermatomyositis (PM/DM) and rheumatoid arthritis (RA), and age and sex matched healthy individuals were tested for ANA by IIF using a commercial kit (Euroimmun, Germany) at 5 dilutions, namely 1:40, 1:80, 1:160, 1:320 and 1:640. Receiver operator characteristics (ROC) curve were constructed to define the optimum dilution that distinguished healthy sera from the diseased ones. RESULTS: Test was performed on 213 sera from 94 healthy individuals, and 43 SLE, 37 RA and 39 DM/PM patients. In healthy individuals, ANA at dilutions 1:40, 1:80, 1:160, 1:320 and 1:640 was positive in 13.8, 4.3, 2.1, 2.1 and 0 per cent respectively, whereas in SLE it was positive in 95.3, 95.3, 65.1, 53.5 and 23.3 per cent respectively. INTERPRETATION & CONCLUSION: ROC curves analysis showed that at 1:40 dilution, sera of 95.3 per cent of SLE and 13.8 per cent of normal individuals were (ANA) positive, whereas at 1:80 dilution it was 95.3 per cent for SLE and 4.3 per cent for healthy individuals. A fluorescent intensity of > or =2 was more specific for SLE. The best discrimination between healthy individuals and the SLE patients was found at screening dilution of 1:80 and fluorescent intensity of > or =2 in our laboratory.

Correlation between methotrexate efficacy & toxicity with C677T polymorphism of the methylenetetrahydrofolate gene in rheumatoid arthritis patients on folate supplementation.

BACKGROUND & OBJECTIVES: C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene has been proposed as a pharmacogenomic marker for toxicity of methotrexate (MTX). We studied the relationship between the C677T gene polymorphism and toxicity and efficacy of MTX in patients with rheumatoid arthritis (RA) on folate supplementation. METHODS: A total of 150 RA patients fulfilling American College of Rheumatology (ACR) criteria and on MTX treatment were evaluated. The mean age of the patients was 42.9 +/- 11.1 yr, mean disease duration was 7.65 +/- 5.2 yr and the mean duration of MTX treatment was 26.1 +/- 20.6 months. Genotype analysis of MTHFR gene was done by PCR and restriction enzyme method. Primary endpoint for treatment efficacy was change in disease activity score 28 (DAS28) from baseline. Drug toxicity was evaluated by blood count, renal and liver function tests and a standardized questionnaire. RESULTS: The mean DAS at baseline was 5.02 +/- 0.8. All patients received 10 mg/wk folic acid supplementation. Forty two per cent (63/150) of the patients had C677T polymorphism of which 4 were homozygous (T/T) and 59 were heterozygous (C/T). The baseline characteristics of the patients with or without polymorphism were comparable. The frequency of adverse events was not increased in patients with C677T polymorphism with 11 patients experiencing adverse events as compared to 19 in the group without polymorphism (of whom 4 and 7 patients respectively discontinued treatment). The C677T polymorphism was not associated with any difference in response to treatment. INTERPRETATION & CONCLUSION: Our findings suggest that C677T polymorphism in the MTHFR gene is not predictive of toxicity or efficacy of MTX treatment in RA patients receiving folate supplementation. Further studies need to be done to look at polymorphisms in other enzymes that may have association with MTX clinical efficacy and toxicity.

Immunomodulatory activity of Semecarpus anacardium extract in mononuclear cells of normal individuals and rheumatoid arthritis patients.

Semecarpus anacardium (SA) Linn. (family Anacardiaceae), is a plant well-known for its medicinal value in Ayurveda. The nut extracts of this plant have been traditionally used as antihelminthic, anti-fungal, anti-carcinogenic and in the treatment of nervous debilities and arthritis. In this study we have evaluated crude ethanolic extract of SA nuts for its anti-inflammatory activities in vitro using peripheral blood and synovial fluid mononuclear cells of healthy individuals and rheumatoid arthritis (RA) patients. SA extract inhibited the spontaneous and LPS induced production of proinflammatory cytokines IL-1beta and IL-12p40 but had no effect on TNF-alpha and IL-6 production, both at protein and mRNA level. The crude extract also suppressed LPS induced nuclear translocation of transcription factors, NF-kappaB and AP-1; the inhibition of NF-kappaB was through the inhibition of IkappaBalpha phosphorylation. The extract also suppressed LPS activated nitric oxide production in mouse macrophage cell line, RAW 264.7. Our results for the first time show that SA extract can inhibit proinflammatory cytokine production and demonstrate its mechanism of action.

Effect of lead exposure on serum immunoglobulins and reactive nitrogen and oxygen intermediate.

Metal toxicants may affect immune regulation with an increased incidence of infectious diseases, cancer or autoimmune diseases. Lead is the leading environmental toxin among heavy metals and has aroused concern, as continuous low-level exposure leads to a variety of health problems. We compared serum immunoglobulins (Ig) and reactive oxygen and nitrogen intermediates (super oxide and nitric oxide (NO)) in culture supernatant of lead-exposed (blood lead; Pb-B > 10 microg/dL) individuals with that of unexposed healthy controls (blood lead < 10 microg/dL). The serum IgA level was significantly increased in lead-exposed individuals in comparison to controls (182 +/- 53 versus 138 +/- 52 mg/dL; P < 0.05). Furthermore, lipopolysaccharide-induced NO production by mouse macrophage cells, RAW 264.7, showed significant suppression (P < 0.05) after treatment with lead acetate (100 ppm). This study suggested that lead could modulate the immune system by targeting the humoral as well as innate immune cells.

Immunosuppressive properties of flavonoids isolated from Boerhaavia diffusa Linn.

Plant extracts have been widely evaluated for possible immunomodulatory properties. We have earlier reported that ethanolic extract of Boerhaavia diffusa root, a plant used in Indian traditional medicine, has significant immunomodulatory potential. B. diffusa hexane, chloroform and ethanol extracts, and two pure compounds Bd-I (eupalitin-3-O-beta-D-galactopyranoside) and Bd-II (eupalitin) were evaluated in vitro for their effect on T cell mitogen (phytohemagglutinin; PHA) stimulated proliferation of human peripheral blood mononuclear cell (PBMC), mixed lymphocyte culture, lipopolysaccharide (LPS) stimulated nitric oxide production by RAW 264.7, PHA and LPS induced IL-2 and TNF-alpha production, in human PBMCs, superoxide production in neutrophils, human natural killer (NK) cell cytotoxicity and nuclear translocation of nuclear factor-(kappa)B and AP-1 in PHA stimulated PBMCs. The chloroform and ethanol extracts inhibited PHA stimulated proliferation of peripheral blood mononuclear cells, two-way MLR, NK cell cytotoxicity as well as LPS induced NO production by RAW 264.7; the hexane extract showed no activity. Bd-I purified from the ethanolic extract at equivalent dose, inhibited PHA-stimulated proliferation of peripheral blood mononuclear cells, two-way MLR and NK cell cytotoxicity as well as LPS induced NO production by RAW 264.7 equally or more effectively than the parent ethanolic extract. Bd-I inhibited production of PHA stimulated IL-2 at the protein and mRNA transcript levels and LPS stimulated TNF-alpha production in human PBMCs; it also blocked the activation of DNA binding of nuclear factor-(kappa)B and AP-1, two major transcription factors centrally involved in expression of the IL-2 and IL-2R gene, which are necessary for T cell activation and proliferation. Our results report selective immunosuppressive activity of B. diffusa leaf extracts and that this activity lies in eupalitin-3-O-beta-D-galactopyranoside (Bd-I) isolated and purified from the ethnaolic extract. Thus, Bd-I could be a candidate for development as an immunosuppressive agent.

Hepatitis B virus genotype A is more often associated with severe liver disease in northern India than is genotype D.

BACKGROUND: The clinical outcome of chronic hepatitis B may depend on hepatitis B virus (HBV) genotype. Data from India on this aspect are limited and contradictory. We studied the frequency of HBV genotypes and their clinical significance. METHODS: Stored sera from patients with chronic HBV infection were tested for HBV genotype using PCR-RFLP. Clinical data, and biochemical and serological parameters were retrieved from medical records; patients were classified as having chronic hepatitis or cirrhosis. RESULTS: Of 70 patients studied (mean age [SD] 38.4 [17.0] years; 63 men; ALT 140 [177] U/L), 32 had chronic hepatitis and 38 had cirrhosis. HBeAg was positive in 50/67 (75%), and anti-HBe in 12/66 (18%). Genotype A was the commonest (37; 53%), followed by D (32; 46%) and C (1; 1%). Patients with genotype A more often had ALT elevation exceeding 1.5 times normal (30/37 [81%] than those with genotype D (18/31 [58%]; p< 0.05). They also more often had positive HBeAg (32/37; 86%) and negative anti-HBe (33/36; 92%) than those with genotype D (18/29 [62%] and 21/29 [72%], respectively; p< 0.05 each). Of 37 patients with genotype A, 23 (62%) had cirrhosis and 14 (38%) had chronic hepatitis; of 32 patients with genotype D, 15 (47%) had cirrhosis and 17 (53%) had chronic hepatitis (p=ns). In the subgroup aged> 25 years, genotype A patients more often had cirrhosis than those with genotype D (23/28 [82%] vs 13/23 [57%]; p < 0.05). CONCLUSION: HBV genotypes A and D were the commonest in our population. Genotype A was more often associated with ALT elevation, HBeAg positivity, absence of anti-HBe and, among those aged 25 years and above, cirrhosis of liver, than was genotype D.

Helicobacter pylori-induced apoptosis in pathogenesis of gastric carcinoma.

BACKGROUND: Despite a possible role of Helicobacter pylori in gastric carcinoma (GC), its pathogenesis is not clear. There is scanty data on apoptosis in GC in relation to H. pylori and CagA antibody. Therefore, we studied gastric epithelial apoptosis in GC and non-ulcer dyspepsia (NUD) with or without H. pylori infection, and the degree of apoptosis in relation to CagA antibody status. METHODS: 20 patients each with GC and NUD were investigated for H. pylori using rapid urease test (RUT), IgG anti-H. pylori and anti-CagA antibodies, histology of endoscopically normal-looking mucosa for H. pylori, intestinal metaplasia (IM), and apoptosis using TUNEL assay. Positivity to one tissue-based (RUT or histology) and one serology based (anti-H. pylori or CagA IgG) test was taken as diagnostic of active H. pylori infection, and negative result in both tissue-based tests suggested its absence. RESULTS: Patients with GC more often had anti-H. pylori IgG (16 of 20 vs. 8 of 20; p=0.02) and a trend towards higher apoptotic index (AI) (48.6 [19.2 to 71.7] vs. 41.4 [11.7 to 63.6]; p=0.06) than NUD. AI was higher in GC (66.7 [57.5 to 71.7] vs. 32.6 [19.2 to 39.8]; p<0.0001) and NUD (58.6 [50.7 to 63.6] vs. 24.4 [11.7 to 32.2]; p<0.0001) infected with H. pylori than in those without infection. AI was also higher in GC than in NUD with H. pylori infection (66.7 [57.5 to 71.7] vs. 58.6 [50.7 to 63.6]; p=0.01). Four of the 20 patients with GC and none with NUD had IM (p=ns). There was no difference in AI in relation to CagA antibody. AI positively correlated with patients' age in presence of H. pylori infection (correlation coefficient=0.5, p=0.03) but not in its absence. CONCLUSION: Exaggerated apoptosis may play a role in H. pylori-mediated gastric diseases including carcinogenesis. AI increases with aging in patients infected with H. pylori.