Sézary T-cell activating factor is a Chlamydia pneumoniae-associated protein

Presence of Chlamydophila pneumoniae DNA in blood cells is a frequent event in patients with the late stage of primary cutaneous lymphomas and with atopic dermatitis

INTRODUCTION

Microbial infection and associated super antigens have been implicated in the pathogenesis of cutaneous T-cell lymphoma (CTCL), and many patients die from complicating bacterial infections. It has been postulated that Chlamydophila pneumoniae (C. pneumoniae) infection may be involved in the pathogenesis of Mycosis fungoides (MF) but published data are limited and controversial.

AIM

To analyze the frequency of (C. pneumoniae) DNA presence in blood samples of lymphoma cases.

MATERIAL AND METHODS

Using Q-PCR method we analyzed the presence of DNA in the blood samples obtained from 57 patients with CTCL (55 - mycosis fungoides (MF)/Sézary syndrome (SS), one primary cutaneous anaplastic large cell lymphoma (CD30+) and one NKT cell lymphoma) and 3 patients with cutaneous B-cell lymphomas, and 120 individuals from control groups (40 patients with psoriasis, 40 patients with atopic dermatitis and 40 healthy controls).

RESULTS

Chlamydophila pneumoniae DNA was identified in 13 of 55 cases in the MF/SS group (23.6%), in 1 patient with CD30+ large cell lymphoma and in 1 of 3 patients with B-cell lymphoma. The presence of C. pneumoniae was confirmed in 1 of 40 psoriatic patients (2.5%), in 5 of 40 patients with atopic dermatitis (12.5%) and in none of 40 healthy individuals. Presence of C. pneumoniae DNA in MF patients was strongly associated with disease progression; rs = 0.756; p = 0.0123 for groups IA → IVB, and was noted more frequently in advanced (III + IV) stages than in early (I-II) stages (p = 0.0139). There are no differences in the mean age of MF/SS patients with and without infection.

CONCLUSIONS

The presence of C. pneumoniae DNA in the blood cells is a frequent event in late stages of MF/SS and may be explained by Th2 shift and suppression of the immune system during the course of the disease.

The Diagnosis, Staging, and Treatment Options for Mycosis Fungoides

Background

Cutaneous T-cell lymphoma (CTCL) represents a spectrum of diseases composed of malignant T lymphocytes. The most common type is mycosis fungoides (MF). An accurate diagnosis of early MF may be difficult because of the varied clinical and histologic expressions of the disease.

Methods

The authors review the epidemiology, possible risk factors, clinical manifestations, diagnostic techniques, staging, prognosis, and treatment options for MF.

Results

The varied and often nonspecific clinical and bistologic presentations of MF may delay diagnosis and staging, thus necessitating further studies such as immunophenotyping and T-cell receptor gene rearrangement analysis.

Conclusions

A multidisciplinary approach to the diagnosis, staging, and treatment of MF assists in optimizing outcomes from management of patients with this disease.

Chlamydia-Like Organisms (CLOs) in Finnish Ixodes ricinus Ticks and Human Skin

Ticks carry several human pathogenic microbes including Borreliae and Flavivirus causing tick-born encephalitis. Ticks can also carry DNA of Chlamydia-like organisms (CLOs). The purpose of this study was to investigate the occurrence of CLOs in ticks and skin biopsies taken from individuals with suspected tick bite. DNA from CLOs was detected by pan-Chlamydiales-PCR in 40% of adult ticks from southwestern Finland. The estimated minimal infection rate for nymphs and larvae (studied in pools) was 6% and 2%, respectively. For the first time, we show CLO DNA also in human skin as 68% of all skin biopsies studied contained CLO DNA as determined through pan-Chlamydiales-PCR. Sequence analyses based on the 16S rRNA gene fragment indicated that the sequences detected in ticks were heterogeneous, representing various CLO families; whereas the majority of the sequences from human skin remained "unclassified Chlamydiales" and might represent a new family-level lineage. CLO sequences detected in four skin biopsies were most closely related to "uncultured Chlamydial bacterium clones from Ixodes ricinus ticks" and two of them were very similar to CLO sequences from Finnish ticks. These results suggest that CLO DNA is present in human skin; ticks carry CLOs and could potentially transmit CLOs to humans.

Role of infectious agents in cutaneous T-cell lymphoma: facts and controversies

The etiology of cutaneous T-cell lymphoma (CTCL) remains unknown, with potential infectious causes having been explored. This contribution evaluates the evidence suggesting an infectious etiology and pathogenesis of the disease, characterizes the relationships between various specific pathogens and CTCL, and discusses some of the difficulties in establishing a causal link between infectious agents and CTCL carcinogenesis. Researchers have evaluated CTCL specimens for evidence of infection with a variety of agents, including human T-lymphotropic virus, Epstein-Barr virus, human herpesvirus-8, and Staphylococcus aureus, although other pathogens also have been detected in CTCL. Although there is significant evidence implicating one or more infectious agents in CTCL, studies to date have not linked definitively any pathogen to disease development, and various studies have yielded conflicting results.

Wasik M, B. Koralov S, Geisler C, Kilian M, Iversen L, Woetmann A, Odum N. Bacterial toxins fuel disease progression in cutaneous T-cell lymphoma

In patients with cutaneous T-cell lymphoma (CTCL) bacterial infections constitute a major clinical problem caused by compromised skin barrier and a progressive immunodeficiency. Indeed, the majority of patients with advanced disease die from infections with bacteria, e.g., Staphylococcus aureus. Bacterial toxins such as staphylococcal enterotoxins (SE) have long been suspected to be involved in the pathogenesis in CTCL. Here, we review links between bacterial infections and CTCL with focus on earlier studies addressing a direct role of SE on malignant T cells and recent data indicating novel indirect mechanisms involving SE- and cytokine-driven cross-talk between malignant- and non-malignant T cells.

Cutaneous malignant lymphomas: Update 2006

Cutaneous lymphomas represent a unique group of lymphomas and are the second most frequent extranodal lymphomas. As with other neoplasias, the pathogenesis is based mainly on a stepwise accumulation of mutations of suppressor genes and oncogenes caused by genetic, environmental or infectious factors. The diagnostic work-up includes clinical, histological, imaging and hematological investigations and in many cases immunohistochemical and molecular biological analyses. The current WHO/EORTC classification of cutaneous lymphomas differentiates "mature T-cell and NK-cell lymphomas", "mature B-cell lymphomas" and "immature hematopoietic malignancies", their variants and subgroups. It is compatible with the WHO classification for neoplasias of the hematopoietic and lymphoid tissue and respects the organ-specific peculiarities of primary cutaneous lymphomas. The assignment of the various types of cutaneous lymphomas into prognostic categories (pre-lymphomatous "abortive" disorders; definite malignant lymphomas of low-grade malignancy; definite malignant lymphomas of high-grade malignancy) provides essential information on the biological behavior and allows an appropriate planning of the therapeutic strategy, which may be topical or systemic and aggressive or non-aggressive. Besides the classical options for therapy, there are new and "experimental" strategies, the efficacy of which has to be studied in clinical trials.

Detection of Helicobacter pylori and Chlamydia pneumoniae genes in primary orbital lymphoma

PURPOSE

Primary orbital non-Hodgkin's lymphoma is a mucosa-associated lymphoid tissue (MALT)-type extranodal marginal zone lymphoma. Chronic antigen stimulation is implicated as a causative agent in the development of some mature B-cell proliferations; for example, there are associations involving Helicobacter pylori with gastric or conjunctival MALT lymphoma and Chlamydia psittaci with ocular adnexal lymphoma. We examined the molecular signatures of H pylori and Chlamydia in eight orbital lymphomas.

METHODS

Polymerase chain reaction (PCR) was performed on DNA extracted from microdissected lymphoma cells. H pylori was detected with the urease B and vac/m2 primers. A multiplex touchdown enzyme time-release PCR assay designed to simultaneously detect Chlamydia trachomatis, Chlamydia pneumoniae, and C psittaci was performed. Authenticity of the PCR-amplified products was verified by Southern blot hybridization.

RESULTS

H pylori DNA was detected in an orbital lymphoma of a French patient who had positive serum H pylori titer. C pneumoniae, but neither C psittaci nor C trachomatis, DNA was detected in another orbital lymphoma of a Chinese patient from Hong Kong. H pylori, C pneumoniae, and C psittaci genes were not found in the other six orbital lymphomas.

CONCLUSION

H pylori or C pneumoniae genomic fingerprints were detected in two of seven primary orbital MALT lymphomas. These findings provide evidence for a possible involvement of particular infectious microorganisms such as H pylori and Chlamydia in primary orbital lymphoma. These different microorganisms may play similar roles in the etiology of orbital MALT lymphomas from different geographic regions. Antibiotic therapy could be considered for orbital MALT lymphomas associated with positive infection.

No evidence of skin infection with Chlamydia pneumoniae in patients with cutaneous T cell lymphoma

Recently, Chlamydia pneumoniae-specific DNA and antigens were reported in the skin of patients with Mycosis fungoides (MF), the most common form of cutaneous T-cell lymphomas. In order to revalidate these data we analyzed skin sections of patients with MF for the expression of three different chlamydial antigens and C. pneumoniae DNA by immunohistochemistry and PCR according to previously described protocolls. Neither C. pneumoniae-specific DNA sequences nor antigens were detected in any of the skin biopses from 24 MF patients tested, suggesting that further studies are needed to establish any pathogenetic relevance of C. pneumoniae in MF.

Cytomegalovirus seropositivity is significantly associated with mycosis fungoides and Sézary syndrome

Although mycosis fungoides (MF) may arise through persistent antigen stimulation, cytomegalovirus (CMV) is not a known risk factor. To study the incidence of seropositivity to viral infections, we compared MF and Sézary Syndrome (SS) patients to healthy bone marrow donors and other historical control groups. Baseline screening serologies at baseline were performed on 116 biopsy-proven MF/SS patients at MD Anderson Cancer Center from 1992 to 2001 and on healthy bone marrow donors evaluated by the transplant service from 1988 to 2001. Antibodies to HTLV-I/II, HIV-1, EBV, and CMV were measured using standard enzyme-linked immunosorbent (ELISA) and membrane enzyme immunoassay (MEIA) assays. One hundred thirteen (97.4%) of all MF/SS patients had positive CMV IgG serologies at initial presentation. Early- and late-stage patients' seropositivity rates were significantly higher than healthy bone marrow donor controls (chi(2).05(df=1) = 71.79). By stage, 98.1% of early-stage MF patients (IA, IB, IIA; 52/53) and 96.8% of late-stage MF and SS patients (IIB-IVB; 61/63) were seropositive compared with healthy bone marrow donors whose seropositivity rate was 57.3% (757/1322). Because the rate of CMV seropositivity increases with age, a subset of cutaneous T-cell lymphoma (CTCL) patients 55 years or younger were compared to age-matched healthy donor controls; their seropositivity rate for CMV was also significantly higher (chi(2).05 05(df=1) = 20.4). EBV titers were positive by serology in 13 patients who were examined prospectively. CMV seropositivity is highly associated with MF and SS, even in the earliest stages of the disease, and is significantly higher than that of healthy and immunocompromised controls.

Atypical lymphoid infiltration occurring at the site of a healed varicella zoster infection

Herpes zoster infection has been associated with a number of cutaneous reactions. The authors report the first case of a patient with an atypical epidermotropic lymphoid infiltrate that arose within skin previously affected by herpes varicella zoster. The differential diagnosis of such lesions and review of literature on previous cutaneous infiltrates occurring at sites of zoster infection are discussed

Chlamydia pneumoniae and chronic skin wounds: a focused review

The genus, Chlamydophilia, as obligate intracellular pathogens, induce chronic scarring in humans. Chlamydia pneumoniae, a common cause of pneumonia, infects endothelial cells and circulating macrophages. Evidence that C. pneumoniae is an opportunistic pathogen in chronic skin ulcers and other inflammatory skin conditions analogous to its role in atherosclerosis is reviewed.

Association between Sézary T cell-activating factor, Chlamydia pneumoniae, and cutaneous T cell lymphoma

Sézary T cell-activating factor (SAF) was originally defined as an inducer of functional interleukin-2 (IL-2) receptors on normal and malignant T cells in patients suffering from Sézary syndrome. In fact, a combination of SAF and IL-2 stimulated the propagation of T cell lines from the peripheral blood mononuclear cells (PBMC) of those patients, with approximately one third of those cell lines containing the predominant malignant clone as determined via cytogenetic and/or T cell receptor gene rearrangement analysis. Although the primary source of SAF was mitogen-stimulated PBMC of a patient with Sézary syndrome, we were unable to isolate the gene encoding SAF from eukaryotic libraries. However, we observed SAF activity in the cytoplasm of one of the malignant cell lines in a complex containing RNA and DNA. This observation led us to consider the possibility that SAF is not of eukaryotic origin. Intracellular pathogens replicate in the cytoplasm of host cells and contain proteins, DNA, and RNA. Using a panel of antichlamydial antibodies with confirmation from polymerase chain reaction primers, we found that most patients with mycosis fungoides were positive for these determinants. Immunoelectron microscopy and protein blotting further confirmed antibody reactivity. We showed that Chlamydia pneumoniae were capable of infecting normal human keratinocytes in culture. We also demonstrated that C. pneumoniae antigen expression was associated with active disease because these determinants were not expressed after psoralen and ultraviolet A therapy. We hypothesize that chronic infection by C. pneumoniae leads to expansion of C. pneumoniae-specific T cells, thereby potentiating the development of cutaneous T cell lymphoma.

Chlamydia pneumoniae inhibits apoptosis in human peripheral blood mononuclear cells through induction of IL-10

Chlamydia pneumoniae is a common cause of pulmonary infection, with serum positivity in at least 50% of the general population. In this study, we report that human PBMCs exposed to C. pneumoniae are resistant to apoptosis induced by the potent photoactivated chemotherapeutic agents 8-methoxypsoralen and hypericin. In contrast, PBMCs treated with a heat-inactivated inoculum exhibit normal susceptibility to apoptosis. We also observed that human PBMCs are responsive to C. pneumoniae infection by secretion of key immune regulatory cytokines, including IL-12 and IL-10. While IL-12 may play an important role in limiting C. pneumoniae proliferation within cells, IL-10 serves an anti-inflammatory function by down-regulating proinflammatory cytokines such as IL-12 and TNF-alpha. Depletion of endogenous IL-10, but not of IL-12, abolished the apoptosis resistance of C. pneumoniae-infected PBMCs. Furthermore, addition of exogenous IL-10, but not IL-12, significantly increased the resistance of control inoculum-treated PBMCs to photoactivated 8-methoxypsoralen- and hypericin-induced apoptosis. Therefore, we conclude that C. pneumoniae possesses an antiapoptotic mechanism. The resistance to apoptosis observed in PBMCs exposed to C. pneumoniae is due, at least partially, to the IL-10 induced during C. pneumoniae infection.