Tumor Necrosis Factor Inhibitors Exacerbate Whipple's Disease by Reprogramming Macrophage and Inducing Apoptosis.

Tropheryma whipplei is the agent of Whipple's disease, a rare systemic disease characterized by macrophage infiltration of the intestinal mucosa. The disease first manifests as arthralgia and/or arthropathy that usually precede the diagnosis by years, and which may push clinicians to prescribe Tumor necrosis factor inhibitors (TNFI) to treat unexplained arthralgia. However, such therapies have been associated with exacerbation of subclinical undiagnosed Whipple's disease. The objective of this study was to delineate the biological basis of disease exacerbation. We found that etanercept, adalimumab or certolizumab treatment of monocyte-derived macrophages from healthy subjects significantly increased bacterial replication in vitro without affecting uptake. Interestingly, this effect was associated with macrophage repolarization and increased rate of apoptosis. Further analysis revealed that in patients for whom Whipple's disease diagnosis was made while under TNFI therapy, apoptosis was increased in duodenal tissue specimens as compared with control Whipple's disease patients who never received TNFI prior diagnosis. In addition, IFN-γ expression was increased in duodenal biopsy specimen and circulating levels of IFN-γ were higher in patients for whom Whipple's disease diagnosis was made while under TNFI therapy. Taken together, our findings establish that TNFI aggravate/exacerbate latent or subclinical undiagnosed Whipple's disease by promoting a strong inflammatory response and apoptosis and confirm that patients may be screened for T. whipplei prior to introduction of TNFI therapy.

Peripheral T-Cell Reactivity to Heat Shock Protein 70 and Its Cofactor GrpE from Tropheryma whipplei Is Reduced in Patients with Classical Whipple's Disease.

Classical Whipple's disease (CWD) is characterized by the lack of specific Th1 response toward Tropheryma whipplei in genetically predisposed individuals. The cofactor GrpE of heat shock protein 70 (Hsp70) from T. whipplei was previously identified as a B-cell antigen. We tested the capacity of Hsp70 and GrpE to elicit specific proinflammatory T-cell responses. Peripheral mononuclear cells from CWD patients and healthy donors were stimulated with T. whipplei lysate or recombinant GrpE or Hsp70 before levels of CD40L, CD69, perforin, granzyme B, CD107a, and gamma interferon (IFN-γ) were determined in T cells by flow cytometry. Upon stimulation with total bacterial lysate or recombinant GrpE or Hsp70 of T. whipplei, the proportions of activated effector CD4+ T cells, determined as CD40L+ IFN-γ+, were significantly lower in patients with CWD than in healthy controls; CD8+ T cells of untreated CWD patients revealed an enhanced activation toward unspecific stimulation and T. whipplei-specific degranulation, although CD69+ IFN-γ+ CD8+ T cells were reduced upon stimulation with T. whipplei lysate and recombinant T. whipplei-derived proteins. Hsp70 and its cofactor GrpE are immunogenic in healthy individuals, eliciting effective responses against T. whipplei to control bacterial spreading. The lack of specific T-cell responses against these T. whipplei-derived proteins may contribute to the pathogenesis of CWD.

-295 T-to-C promoter region IL-16 gene polymorphism is associated with Whipple's disease.

Whipple's disease (WD) is a rare systemic condition caused, in genetically predisposed subjects, by Tropheryma whipplei, a common bacterium widespread in the environment. The relevance of genetic predisposition in WD is shown by the association with HLA alleles DRB1*13 and DQB1*06 and by the demonstration that, in patients with WD, the cytokine genetic profile is skewed toward a Th2 and Treg response. Since IL-16 is involved in hampering the development of a protective macrophagic response against Tropheryma whipplei, we investigated whether the genetic background of IL-16 is different between patients with WD and controls. The -295 T-to-C polymorphism of the promoter region of the IL-16 gene was studied in 90 patients with WD and 152 healthy controls. Levels of serum IL-16 protein were also tested. The frequency of the wild type T allele was significantly higher in patients with WD compared to the controls (155/180 vs. 235/304; p = 0.02 for the Chi(2) test), odds ratio 1.82 [95 % confidence interval (CI) 1.07-3.10]. The TT genotype was found in 65/90 patients with WD and 88/152 controls (p = 0.026). No relationship was found between serum levels of IL-16 and genotypes. Although the functional consequences of this genetic background on levels of IL-16 and on the course of the disease are still unknown, we found, for the first time, that the wild type T allele and the TT genotype of the -295 polymorphism are associated with WD.

Sewage workers with low antibody responses may be colonized successively by several Tropheryma whipplei strains.

OBJECTIVES: Asymptomatic faecal carriage of Tropheryma whipplei, the agent of Whipple's disease, is reported among sewage workers. However, the potential development of such carriage is unknown. A 7-year follow-up of T. whipplei-carrying sewage workers is reported. METHODS: Nineteen sewage workers previously detected as faecal carriers of T. whipplei were followed to ascertain the chronicity of their carriage. Faeces were tested by molecular assays using quantitative real-time PCR specifically targeting T. whipplei. Serological anti-T. whipplei Western blotting was also performed. RESULTS: Seventy-nine percent (15/19) of workers exhibited a strong immune response against T. whipplei. Among these, five were followed for more than 1 year. Four maintained a strong response, with three carrying the same strain and one becoming negative. The fifth exhibited a decreased immune response, a negative faeces result, and subsequent carriage of another strain. Three individuals with low immune responses were also followed. Two never developed a response, with one carrying the same strain and one becoming negative and then positive with another strain; the third developed a strong response and became negative. CONCLUSIONS: Chronic T. whipplei carriers appear to be protected against reinfection, but those with low or decreasing antibody levels may be re-colonized by another strain.

Role of dendritic cells in the pathogenesis of Whipple's disease.

Accumulation of Tropheryma whipplei-stuffed macrophages in the duodenum, impaired T. whipplei-specific Th1 responses, and weak secretion of interleukin-12 (IL-12) are hallmarks of classical Whipple's disease (CWD). This study addresses dendritic cell (DC) functionality during CWD. We documented composition, distribution, and functionality of DC ex vivo or after in vitro maturation by fluorescence-activated cell sorting (FACS) and by immunohistochemistry in situ. A decrease in peripheral DC of untreated CWD patients compared to healthy donors was due to reduced CD11c(high) myeloid DC (M-DC). Decreased maturation markers CD83, CD86, and CCR7, as well as low IL-12 production in response to stimulation, disclosed an immature M-DC phenotype. In vitro-generated monocyte-derived DC from CWD patients showed normal maturation and T cell-stimulatory capacity under proinflammatory conditions but produced less IL-12 and failed to activate T. whipplei-specific Th1 cells. In duodenal and lymphoid tissues, T. whipplei was found within immature DC-SIGN(+) DC. DC and proliferating lymphocytes were reduced in lymph nodes of CWD patients compared to levels in controls. Our results indicate that dysfunctional IL-12 production by DC provides suboptimal conditions for priming of T. whipplei-specific T cells during CWD and that immature DC carrying T. whipplei contribute to the dissemination of the bacterium.

Immunopathology of immune reconstitution inflammatory syndrome in Whipple's disease.

During antimicrobial treatment of classic Whipple's disease (CWD), the chronic systemic infection with Tropheryma whipplei, immune reconstitution inflammatory syndrome (IRIS), is a serious complication. The aim of our study was to characterize the immunological processes underlying IRIS in CWD. Following the definition of IRIS, we describe histological features of IRIS and immunological parameters of 24 CWD IRIS patients, 189 CWD patients without IRIS, and 89 healthy individuals. T cell reconstitution, Th1 reactivity, and the phenotype of T cells were described in the peripheral blood, and infiltration of CD4(+) T cells and regulatory T cells in the duodenal mucosa was determined. During IRIS, tissues were heavily infiltrated by CD3(+), predominantly CD45RO(+)CD4(+) T cells. In the periphery, initial reduction of CD4(+) cell counts and their reconstitution on treatment was more pronounced in CWD patients with IRIS than in those without IRIS. The ratio of activated and regulatory CD4(+) T cells, nonspecific Th1 reactivity, and the proportion of naive among CD4(+) T cells was high, whereas serum IL-10 was low during IRIS. T. whipplei-specific Th1 reactivity remained suppressed before and after emergence of IRIS. The findings that IRIS in CWD mainly are mediated by nonspecific activation of CD4(+) T cells and that it is not sufficiently counterbalanced by regulatory T cells indicate that flare-up of pathogen-specific immunoreactivity is not instrumental in the pathogenesis of IRIS in CWD.

Whipple's disease.

Whipple's disease is a chronic, systemic infection caused by Tropheryma whipplei. Gene amplification, isolation and DNA sequencing of T whipplei have extended our knowledge of this pathogen, which is now recognised as a ubiquitous commensal bacterium. The spectrum of signs associated with T whipplei has now been extended beyond the classic form, which affects middle-aged men, and begins with recurrent arthritis followed several years later by digestive problems associated with other diverse clinical signs. Children may present an acute primary infection, but only a small number of people with a genetic predisposition subsequently develop authentic Whipple's disease. This bacterium may also cause localised chronic infections with no intestinal symptoms: endocarditis, central nervous system involvement, arthritis, uveitis and spondylodiscitis. An impaired TH1 immune response is seen. T whipplei replication in vitro is dependent on interleukin 16 and is accompanied by the apoptosis of host cells, facilitating dissemination of the bacterium. In patients with arthritis, PCR with samples of joint fluid, saliva and stools has become the preferred examination for diagnosis. Immunohistochemical staining is also widely used for diagnosis. Treatment is based on recent microbiological data, but an immune reconstitution syndrome and recurrence remain possible. The future development of serological tests for diagnosis and the generalisation of antigen detection by immunohistochemistry should make it possible to obtain a diagnosis earlier and thus to decrease the morbidity, and perhaps also the mortality, associated with this curable disease which may, nonetheless, be fatal if diagnosed late or in an extensive systemic form.

Cytokine genetic profile in Whipple's disease.

Whipple's disease (WD) is a very rare chronic systemic condition characterised by a Th2/T regulatory (Treg) dysregulated immune response versus Tropheryma whipplei, a bacterium widely diffuse in the environment. To investigate whether this Th2/Treg polarised response has a genetic background, we investigated the Th1, Th2, Th17 and Treg cytokine genetic profile of 133 patients with WD. Thanks to the European Consortium on WD (QLG1-CT-2002-01049), the polymorphism of 13 cytokine genes was analysed in 111 German and 22 Italian patients using the polymerase chain reaction with sequence-specific primers (PCR-SSP) technique. The frequencies of the genotypes, haplotypes and functional phenotypes were compared with those obtained in 201 German and 140 Italian controls. Clinical heterogeneity was also considered. Functionally, WD patients may be considered as low producers of TGF-ß1, having an increased frequency of the genotype TGF-ß1+869C/C,+915C/C [12.3 % vs. 3.81 %, odds ratio (OR) = 4.131, p = 0.0002] and high secretors of IL-4, carrying the genotype IL-4-590T/T (5.34 % vs. 1.17 %, OR = 5.09, p = 0.0096). No significant association was found between cytokine polymorphism and clinical variability. Analogously to the recent cellular findings of a Th2/Treg polarised response, we showed that the cytokine genetic profile of WD patients is skewed toward a Th2 and Treg response. This was similar in both German and Italian populations. However, the significant deviations versus the controls are poorer than that expected on the basis of these recent cellular findings.

Whipple disease a century after the initial description: increased recognition of unusual presentations, autoimmune comorbidities, and therapy effects.

Although Whipple disease was described over a century ago, it remains challenging to recognize. To better understand the presentation of Whipple disease, we undertook a clinicopathologic study of our experience since implementation of the Whipple immunohistochemical stain. Twenty-three biopsy specimens from 15 patients were identified, and an association with immunomodulatory conditions was noted. Whipple disease involved the small intestine (19), brain (2), breast (1), and retroperitoneum (1). Whipple disease was suspected by 3 clinicians and by the majority of pathologists (9). Alternative clinical impressions included lymphoma, celiac disease, Crohn vasculitis, sepsis, an inflammatory process, liposarcoma, rheumatoid arthritis, seizure disorder, cerebrovascular accident, xanthoma, and central nervous system neoplasm. The nonspecific nature of the disease presentation likely contributed to the extended period between onset of symptoms and a definitive diagnosis, which ranged from at least 1 year to over 10 years. One patient died of unknown causes, and both patients with detailed follow-up had clinically persistent disease. We also describe Whipple disease with therapy effects, including partial and complete histologic treatment effects. Awareness of the unusual clinicopathologic presentations of Whipple disease is essential for timely diagnosis of this potentially lethal disease.

Regulatory T cells in patients with Whipple's disease.

Classical Whipple's disease (CWD) is caused by chronic infection with Tropheryma whipplei that seems to be associated with an underlying immune defect. The pathognomonic hallmark of CWD is a massive infiltration of the duodenal mucosa with T. whipplei-infected macrophages that disperse systemically to many other organ systems. An alleviated inflammatory reaction and the absence of T. whipplei-specific Th1 reactivity support persistence and systemic spread of the pathogen. In this article, we hypothesized that regulatory T cells (T(reg)) are involved in immunomodulation in CWD, and we asked for the distribution, activation, and regulatory capacity of T(reg) in CWD patients. Whereas in the lamina propria of CWD patients before treatment numbers of T(reg) were increased, percentages in the peripheral blood were similar in CWD patients and healthy controls. However, peripheral T(reg) of CWD patients were more activated than those of controls. Elevated secretion of IL-10 and TGF-ß in the duodenal mucosa of CWD patients indicated locally enhanced T(reg) activity. Enhanced CD95 expression on peripheral memory CD4(+) T cells combined with reduced expression of IFN-γ and IL-17A upon polyclonal stimulation by CD4(+) cells from untreated CWD patients further hinted to T(reg) activity-related exhaustion of effector CD4(+) T cells. In conclusion, increased numbers of T(reg) can be detected within the duodenal mucosa in untreated CWD, where huge numbers of T. whipplei-infected macrophages are present. Thus, T(reg) might contribute to the chronic infection and systemic spread of T. whipplei in CWD but in contrast prevent mucosal barrier defect by reducing local inflammation.

Changing paradigms in Whipple's disease and infection with Tropheryma whipplei.

More than a century after its first description through G.H. Whipple, the understanding of the chronic multisystemic infection called Whipple's disease is still limited. However, within recent years the knowledge about diagnosis and treatment, the pathogenesis, and the biology of the agent itself have been improved by molecular biological and immunological methods. Despite the ubiquitous presence of the causative bacterium Tropheryma whipplei, Whipple's disease is very rare, and immunogenetic host factors rather than the genotype of the agent influence the course of infection. Since the clinical features of classical Whipple's disease are non-specific and the spectrum of isolated organ-specific manifestations might be underestimated, diagnosis often still is a challenge. Moreover, besides classical Whipple's disease, there are newly recognized infections with T. whipplei, which do not fit in the concept of classical Whipple's disease, for example, acute self-limiting infection and isolated T. whipplei endocarditis. Antibiotic therapy is usually successful. However, several problems are still unresolved, of which the most important are the following: which antibiotic should be used; how long treatment should be continued; how the immunoreconstitution inflammatory syndrome, which may occur after initiation of treatment, should be managed; and which is the best treatment of severe neurological manifestations.

Specific and nonspecific B-cell function in the small intestines of patients with Whipple's disease.

Whipple's disease is a chronic multisystemic infection caused by Tropheryma whipplei that is characterized by arthritis, weight loss, and diarrhea. The immunological defects in the duodenal mucosa, the site of major replication of the agent underlying the pathogenesis of Whipple's disease, are poorly understood. Mucosal immunoglobulins are essential for the defense against intestinal pathogens; therefore, we analyzed the B-cell response in duodenal specimens and sera of Whipple's disease patients. Whereas systemic immunoglobulin production was affected only marginally, duodenal biopsy specimens of Whipple's disease patients contained reduced numbers of immunoglobulin-positive plasma cells and secreted less immunoglobulin compared to healthy controls but showed a weak secretory IgA response toward T. whipplei. This T. whipplei-specific intestinal immune response was not observed in controls. Thus, we were able to demonstrate that general mucosal immunoglobulin production in Whipple's disease patients is impaired. However, this deficiency does not completely abolish T. whipplei-specific secretory IgA production that nonetheless does not protect from chronic infection.

Type I interferon induction is detrimental during infection with the Whipple's disease bacterium, Tropheryma whipplei.

Macrophages are the first line of defense against pathogens. Upon infection macrophages usually produce high levels of proinflammatory mediators. However, macrophages can undergo an alternate polarization leading to a permissive state. In assessing global macrophage responses to the bacterial agent of Whipple's disease, Tropheryma whipplei, we found that T. whipplei induced M2 macrophage polarization which was compatible with bacterial replication. Surprisingly, this M2 polarization of infected macrophages was associated with apoptosis induction and a functional type I interferon (IFN) response, through IRF3 activation and STAT1 phosphorylation. Using macrophages from mice deficient for the type I IFN receptor, we found that this type I IFN response was required for T. whipplei-induced macrophage apoptosis in a JNK-dependent manner and was associated with the intracellular replication of T. whipplei independently of JNK. This study underscores the role of macrophage polarization in host responses and highlights the detrimental role of type I IFN during T. whipplei infection.

Impaired immune functions of monocytes and macrophages in Whipple's disease.

BACKGROUND & AIMS: Whipple's disease is a chronic multisystemic infection caused by Tropheryma whipplei. Host factors likely predispose for the establishment of an infection, and macrophages seem to be involved in the pathogenesis of Whipple's disease. However, macrophage activation in Whipple's disease has not been studied systematically so far. METHODS: Samples from 145 Whipple's disease patients and 166 control subjects were investigated. We characterized duodenal macrophages and lymphocytes immunohistochemically and peripheral monocytes by flow cytometry and quantified mucosal and systemic cytokines and chemokines indicative for macrophage activation. In addition, we determined duodenal nitrite production and oxidative burst induced by T whipplei and by other bacteria. RESULTS: Reduced numbers of duodenal lymphocytes, increased numbers of CD163(+) and stabilin-1(+), reduced numbers of inducible nitric synthase+ duodenal macrophages, and increased percentages of CD163(+) peripheral monocytes indicated a lack of inflammation and a M2/alternatively activated macrophage phenotype in Whipple's disease. Incubation with T whipplei in vitro enhanced the expression of CD163 on monocytes from Whipple's disease patients but not from control subjects. Chemokines and cytokines associated with M2/alternative macrophage activation were elevated in the duodenum and the peripheral blood from Whipple's disease patients. Functionally, Whipple's disease patients showed a reduced duodenal nitrite production and reduced oxidative burst upon incubation with T whipplei compared with healthy subjects. CONCLUSIONS: The lack of excessive local inflammation and alternative activation of macrophages, triggered in part by the agent T whipplei itself, may explain the hallmark of Whipple's disease: invasion of the intestinal mucosa with macrophages incompetent to degrade T whipplei.

[First centenary of Whipple's disease]. / Cumple su primer centenario la enfermedad de Whipple.

Whipple's disease is an infrequent multisystemic infection caused by a gram-positive bacterium: Tropheryma whippelii, which after several studies has been characterized as an actinomiceto por 16Sr RNA. It occurs with multiple symptoms, the principal of which are diarrhea, weight loss, stomach pain and arthralgias. Arthritis or artralgia may appear as an isolated symptom and eventually through the years additional digestive, cardiovascular and/or neurological symptoms arise. Diverse immunological abnormalities usually present before or after clinical symptoms are first discovered. Currently there are cabinet, endoscopic, radiological, tomographic and laboratory studies which can help to make a definitive diagnosis, such as the duodenal biopsy submitted to the Schiff test, to the polimerasa chain or an electronic microscopy in order to see the intracellular bacteria in the macrophage and for immunohistochemistry to see specific antibodies to Whipple's disease. Treatment is trimetoprim/sulfametoxazol, it is suggested transfer factor too.

A paradoxical Tropheryma whipplei western blot differentiates patients with whipple disease from asymptomatic carriers.

BACKGROUND: Tropheryma whipplei is a bacterium that causes Whipple disease. However, T. whipplei can be carried in the gut of asymptomatic people, which may lead to difficulty in the interpretation of positive stool sample test results. METHODS: This study included 60 patients with classic Whipple disease at the time of diagnosis and 26 T. whipplei carriers. Western blots testing for total immunoglobulin (Ig), IgG, IgM, and IgA were performed using glycosylated and deglycosylated T. whipplei. A blind test involving 10 patients and 10 carriers was performed. Sera samples from 32 treated patients were tested for total immunoglobulin. RESULTS: Total immunoglobulin from patients with classic Whipple disease exhibited either a lack of reaction (23 [38%] of 60 patients) or a decrease in reaction (33 [55%] of 60 patients) with a T. whipplei glycoprotein of 110 kDa after deglycosylation. Only 4 patients exhibited a stronger immune response than that which was observed for carriers (21 [81%] of 26 carriers). Five carriers presented a response profile similar to that for the patients. IgM (4 [7%] of 60 patients) or IgA (1 [2%] of 60 patients) responses were rarely observed but were exclusive to patients. Overall, results were consistent and reproducible. Antibiotic therapy had no effect on the serological profiles of the patients. CONCLUSIONS: Western blot serology is useful to distinguish between carriers and patients; paradoxical responses of the antibodies were investigated.

[Whipple's disease. Do we think of it enough?]. / Whipple-kór. Vajon gondolunk-e mindig rá?

UNLABELLED: Whipple's disease is a chronic, systemic, relapsing bacterial illness, which is always fatal without treatment, and means a diagnostic challenge for both clinicians and pathologists. It occurs in Caucasian, white, middle-aged men in 80 % of the cases. CASE REPORT: The authors present three cases, and review the etiology, clinical features, presumed pathomechanism and the possibilities of treatment. CONCLUSION: Several immune-mechanisms have been discussed in the background of Whipple's disease, but their primary or secondary role is yet undetermined. First of all, this is a gastrointestinal disease; however, extraintestinal symptoms may be present many years before the final diagnosis. The histological hallmark for the diagnosis is the presence of numerous macrophages in the duodenal mucosa showing periodic acid-Schiff (PAS)-positive inclusions, and the polymerase chain reaction. The choice of antibiotics and the length of the treatment is empiric, but in most cases there is an immediate response to therapy. Relapses are common, especially the involvements of central nervous system.