Histological and immunohistochemical features in fatal acute fulminant hepatitis E.

BACKGROUND: Hepatitis E is being increasingly recognized as an emerging infection in developed countries. Data on histological findings and nature of inflammatory cell infiltrate in liver in this disease are quite sparse. AIMS: This study was planned to study the histological features and the type of inflammatory infiltrate in liver biopsies of patients with acute fulminant hepatitis E. MATERIALS AND METHODS: We retrieved postmortem liver biopsies of 11 Indian patients with fulminant hepatitis E, and compared these with biopsies from seven patients with fulminant hepatitis B. RESULTS: Biopsies from acute fulminant hepatitis E showed varying degrees of hepatocyte necrosis, mixed portal and lobular inflammation, accompanied by bile ductular proliferation, lymphocytic cholangitis, Kupffer cell prominence, cholestasis, apoptotic bodies, pseudo-rosette formation, steatosis, and presence of plasma cells in portal tracts. Interface hepatitis was more frequent in acute hepatitis B than in acute hepatitis E (100% vs 20%; P<0.05). These findings differ from those reported in cases with autochthonous hepatitis E in Europe. On immunohistochemistry, lymphocyte infiltrate consisted predominantly of CD3 + T cells in both hepatitis E and hepatitis B; these cells contained a predominant cytotoxic (CD8 + ) cell subpopulation in 81.8% of cases with hepatitis E and in 50% of cases with hepatitis B. CONCLUSION: Our findings suggest that histological changes in HEV infection may vary with geographical location because of prevalent HEV genotypes, and that CD8 + lymphocytes play a role in HEV-induced liver injury.

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.

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.

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.

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.

Genetic contribution and associated pathophysiology in end-stage renal disease.

End-stage renal disease (ESRD) or chronic kidney disease (CKD) is the terminal state of the kidney when its function has been permanently and irreversibly damaged. A wide variety of etiologies and pathological processes culminate in ESRD, and both environmental and genetic factors contribute to its development and progression. Various reports suggest that susceptibility to develop ESRD has a significant genetic component. These studies include familial aggregation studies, comparisons of incidence rates between different racial or ethnic populations, and segregation analysis. Genetic approaches have been used to identify genes that contribute to genetic susceptibility. Many studies have now been carried out assessing the contribution of specific "candidate genes", which correlate with different functions that are involved in the renal pathogenesis. Independent studies for specific associated genes have frequently provided contradictory results. This may be due, in part, to the modest contribution to genetic susceptibility which these genes impart. With the availability of different genomewide association studies, chromosomal regions harboring novel, previously unrecognized, genes that may contribute to renal diseases have been recently reported. We have focused on different genetic studies conducted on ESRD and have discussed the strength and weaknesses of these studies. The nonmuscle myosin heavy chain 9 gene (MYH9) and renin-angiotensin system (RAS) have been discussed in detail.

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.

Increased interleukin-10 production without expansion of CD4+CD25+ T-regulatory cells in early stable renal transplant patients on calcineurin inhibitors.

BACKGROUND: Increasing long-term allograft survival is the main challenge in organ transplantation, and allograft loss due to chronic rejection has been found to correlate with episodes of early acute rejection. It is important to understand the mechanisms that maintain the donor-specific hyporesponsive state. This study prospectively evaluates immune events related to donor-specific hyporesponsiveness in the stable transplant patients on calcineurin inhibitors (CNIs). METHODS: Peripheral blood mononuclear cells of transplant recipients on CNI (n=19) were tested in mixed lymphocyte reaction (MLR) against donor and third-party peripheral blood mononuclear cells pretransplant and at 6 to 8 weeks, 14 to 18 weeks, and 6 to 8 months posttransplant. Interleukin (IL)-10 and transforming growth factor-beta were quantitated in cultures supernatants by enzyme-linked immunosorbent assay. CD4CD25 T-regulatory cells (Tregs) were enumerated using flow cytometry. RESULTS: All patients showed sharp decline in anti-donor and third-party MLR response at 6 to 8 weeks posttransplant with progressive decline up to 6 to 8 months. This was accompanied by increased IL-10 levels in the supernatant at all the follow-ups. Transforming growth factor-beta level in the supernatant was significantly lower at 14 to 18 weeks. Frequency of CD4CD25 Tregs showed a significant decrease at 6 to 8 weeks posttransplant, which was sustained up to 6 to 8 months. CONCLUSION: The study shows that the maintenance of good graft function in early posttransplant period in recipients on CNI is associated with a decrease in donor-specific and third-party MLRs. There is a decline in Treg numbers along with increased IL-10 levels. High IL-10, probably from a non-Tregs source, may have an important role in maintaining hyporesponsiveness and good graft function.

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.

Frequency of Helicobacter pylori and CagA antibody in patients with gastric neoplasms and controls: the Indian enigma.

BACKGROUND: Despite association between H. pylori and gastric neoplasm (GN) from the developed world, studies from India, where infection is more common and acquired early, are scant and contradictory. METHODS: Two hundred and seventy-nine patients with GN from two northern and one eastern Indian centers during the period 1997-2005, 101 non-ulcer dyspepsia (NUD), and 355 healthy volunteers (HV) were evaluated for H. pylori [rapid urease test (RUT), histology and anti-H. pylori, and CagA IgG serology]. RESULTS: Patients with GN [263 gastric carcinoma and 16 (6%) primary gastric lymphoma, 208 male] were older than HV (n = 355, 188 male) and NUD (n = 101, 54 male) patients (53 +/- 12 versus 44 +/- 17 and 43 +/- 13 years, respectively; P < 0.001). Eastern Indian patients with GN (n = 145) were younger than those from northern India (n = 134; 52 +/- 12 versus 55 +/- 12 years; P < 0.007, t-test). In GN and NUD patients H. pylori positivity by RUT [86/225 (38%) versus 46/101 (46%)], anti-H. pylori IgG [154/198 (78%) versus 85/101 (84%)], and histology [136/213 (64%) versus 55/101 (55%)] were comparable (chi(2)-test). Serum IgG anti-H. pylori antibody was more common among HV than among GN patients [300/355 (85%) versus 154/198 (78%); P = 0.04, chi(2)-test]. Intestinal metaplasia was more common in GN than in NUD patients [101/252 (40%) versus 2/98 (2%), P < 0.000, chi(2)-test]. CagAIgG was more common in GN than in NUD patients [124/163 (76%) versus 64/101 (63%)] but comparable to that in HV patients [87/98 (89%), P = NS]. CONCLUSION: Frequency of H. pylori as detected using endoscopy and serology-based tests is not higher among patients with GN as compared with controls in India.

Roles and mechanism of natural killer cells in clinical and experimental transplantation.

Natural killer (NK) cells are an important component of the innate immune response against intracellular pathogens and also play a role in the tissue inflammation associated with autoimmune diseases. Being a potent effector response, it must be well regulated in order to avoid unwanted destruction of normal tissues. Indeed, NK cells are unique in bearing both stimulatory and inhibitory receptor tolerance. The fine balance between activation and inhibition that decides their final action provides an opportunity for their possible modulation in specific therapeutic settings. The recent evidence implicating NK cells in promoting tolerance during allotransplantation is one such setting that has important implications for a successful transplant. This review provides an insight into NK cell biology and their involvement in allotransplant tolerance.

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.

Presence of hepatitis E virus in sewage in Northern India: frequency and seasonal pattern.

Outbreaks of acute hepatitis E, associated with consumption of contaminated drinking water, are frequent in India. Sewage is a major source for contamination of surface water. Data on the presence of hepatitis E virus (HEV) in sewage in India are limited. The aim of this study was to look for the presence of HEV RNA in concentrates of sewage specimens collected from a major open sewage drain in Lucknow, India during August 2004 to July 2006, by the polymerase chain reaction, using primers specific for human HEV (genotype 1) or Indian swine HEV (genotype 4). Of the 192 sewage specimens tested, 79 (41%) showed presence of human HEV RNA. The positivity rate was higher during the second year (52/103 [51%]) than during the first year (27/89 [30%]; P = 0.005). The seasonal pattern of HEV RNA positivity was as follows: winter months (November to February): 28 of 61 (46%); summer months (March to June): 36 of 66 (55%); and, monsoon months (July to October) 15 of 65 (23%). There was no reported outbreak of hepatitis E in the city during the study period. Swine HEV RNA was not detected in any of the 69 specimens tested. Repeat testing confirmed the reproducibility of the results. In addition, nucleic acid sequencing of six sewage isolates showed that these belonged to HEV genotype 1. The study suggests that HEV infection and fecal viral excretion may be common in HEV-endemic regions throughout the year even during non-epidemic periods.

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.

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.

Withania somnifera inhibits NF-kappaB and AP-1 transcription factors in human peripheral blood and synovial fluid mononuclear cells.

Withania somnifera (WS) is an important herb with known antiinflammatory activity. Its molecular mechanism of action has not been investigated. The effect of a WS crude ethanol extract was studied on peripheral blood mononuclear cells of normal individuals and rheumatoid arthritis (RA) patients and synovial fluid mononuclear cells of RA patients in vitro. The WS extract significantly suppressed lipopolysaccharide (LPS) induced production of proinflammatory cytokines TNF-alpha, IL-1beta and IL-12p40 in normal individuals and RA patients, but had no effect on IL-6 production at the protein and transcript level. WS also suppressed LPS activated nitric oxide production in the mouse macrophage cell line, RAW 264.7. The extract inhibited nuclear translocation of the transcription factors NF-kappaB and AP-1 and phosphorylation of IkappaBalpha in normal and RA patients' mononuclear cells. HPLC analysis of the crude extract showed the presence of withaferin A and pure withaferin A also inhibited NF-kappaB translocation. The study demonstrated that the WS crude ethanol extract suppressed the production of proinflammatory molecules in vitro. This activity is partly through the inhibition of transcription factors NF-kappaB and AP-1 by the constituent withanolide. The role of additional constituents needs to be studied. Studies on the mechanism of action of the extract may yield potentially useful compounds for the treatment of inflammatory diseases.