Modulation of the skin microbiome in cutaneous T-cell lymphoma delays tumour growth and increases survival in the murine EL4 model

Cutaneous T-cell lymphomas (CTCL) are a group of lymphoproliferative disorders of skin-homing T cells causing chronic inflammation. These disorders cause impairment of the immune environment, which leads to severe infections and/or sepsis due to dysbiosis. In this study, we elucidated the host-microbial interaction in CTCL that occurs during the phototherapeutic treatment regime and determined whether modulation of the skin microbiota could beneficially affect the course of CTCL. EL4 T-cell lymphoma cells were intradermally grafted on the back of C57BL/6 mice. Animals were treated with conventional therapeutics such as psoralen + UVA (PUVA) or UVB in the presence or absence of topical antibiotic treatment (neomycin, bacitracin, and polymyxin B sulphate) as an adjuvant. Microbial colonisation of the skin was assessed to correlate with disease severity and tumour growth. Triple antibiotic treatment significantly delayed tumour occurrence (p = 0.026), which prolonged the survival of the mice (p = 0.033). Allocation to phototherapeutic agents PUVA, UVB, or none of these, along with antibiotic intervention, reduced the tumour growth significantly (p = 0.0327, p ≤ 0.0001, p ≤ 0.0001 respectively). The beta diversity indices calculated using the Bray-Curtis model showed that the microbial population significantly differed after antibiotic treatment (p = 0.001). Upon modulating the skin microbiome by antibiotic treatment, we saw an increase in commensal Clostridium species, e.g., Lachnospiraceae sp. (p = 0.0008), Ruminococcaceae sp. (p = 0.0001)., Blautia sp. (p = 0.007) and a significant reduction in facultative pathogens Corynebacterium sp. (p = 0.0009), Pelomonas sp. (p = 0.0306), Streptococcus sp. (p ≥ 0.0001), Pseudomonas sp. (p = 0.0358), and Cutibacterium sp. (p = 0.0237). Intriguingly, we observed a significant decrease in Staphylococcus aureus frequency (p = 0.0001) but an increase in the overall detection frequency of the Staphylococcus genus, indicating that antibiotic treatment helped regain the microbial balance and increased the number of non-pathogenic Staphylococcus populations. These study findings show that modulating microbiota by topical antibiotic treatment helps to restore microbial balance by diminishing the numbers of pathogenic microbes, which, in turn, reduces chronic inflammation, delays tumour growth, and increases survival rates in our CTCL model. These findings support the rationale to modulate the microbial milieu during the disease course of CTCL and indicate its therapeutic potential.

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.

Mycosis on mycosis fungoides: zoophilic dermatophytosis selectively superimposed on pre-existing cutaneous T-cell lymphoma (mycosis fungoides) plaques

We report a case of tinea corporis caused by a cattle-derived strain of Trichophyton mentagrophytes in a 44-year-old male affected by cutaneous T-cell lymphoma (CTCL, so-called mycosis fungoides). Fungal colonization of glabrous skin was strictly confined within pre-existing lymphomatous plaques. Either oral itraconazole or griseofulvin, or topical terbinafine were ineffective until the patient, who was treated with systemic retinoids and interferon-alpha for his CTCL, was shifted from leucocyte to lymphoblastoid interferon. The hypothesis that a local immunodisturbance could be responsible for the selective superimposition of tinea on CTCL lesions ('mycosis on mycosis'), and that such an immunodisturbance could be partially corrected by the interferon switch is discussed.

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.

Enterococcal eschars in cutaneous T-cell lymphoma tumors: a distinct clinical entity

Cutaneous T-cell lymphomas (CTCL) are extranodal non-Hodgkin's T-cell lymphomas that present in the skin, the most common form being mycosis fungoides. The progression of disease is associated with acquired immunodeficiency and increased susceptibility to infections. Ten CTCL patients presented with dark brown to black eschars overlying ulcerated tumors that cultured positive for Enterococcus and healed with appropriate antibiotic therapy. Enterococcal infections in CTCL tumors may be recognized as a distinct clinical entity requiring specific intervention.

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

We previously identified a protein that was stimulatory for malignant Sézary T cells, termed Sézary T-cell activating factor (SAF). However, the identity of this protein has not been fully elucidated, nor has it's role been determined in the pathogenesis of cutaneous T-cell lymphoma (CTCL). The basis for epidermotropism and proliferation of malignant cells in the skin of patients with CTCL is unknown. Using a monoclonal antibody inhibitory for SAF activity, we demonstrated that SAF is present in the skin of 16 of 27 samples from patients with mycosis fungoides, the predominant form of CTCL. In this report, the SAF determinant is demonstrated to be associated with Chlamydia pneumoniae bacteria by immunohistochemistry, immunoelectron microscopy, and culture analysis. Reactivity of antibodies against an outer membrane protein of C. pneumoniae or against the lipopolysaccharide of Chlamydiae spp. demonstrated that these determinants are coexpressed in 90% of the SAF-positive samples. We confirmed the presence of C. pneumoniae DNA and RNA in the skin by PCR and reverse transcription-PCR and by sequence analysis of the PCR products. The expression of the C. pneumoniae antigens and SAF appears to be associated with active disease in that C. pneumoniae antigens were absent or greatly diminished in the skin of three patients examined after Psoralen and long-wave UVA radiation treatment. Our results suggest that SAF is a Chlamydia-associated protein and that further investigation is warranted to determine whether SAF and C. pneumoniae play a role in the pathogenesis of CTCL.

The role of human T-cell lymphotropic viruses (HTLV-I and II) in cutaneous T-cell lymphomas

Although an association between the human T cell lymphotropic viruses (HTLV-I and II) and cutaneous T cell lymphoma (CTCL) has long been suspected, only a minor fraction of patients with this disease have antibodies to the viral structural proteins. However, the consistent finding of HTLV-like particles in cultures of peripheral blood mononuclear cells (PBMC) from such patients has prompted a continued effort to find evidence linking the virus to this disease. Capitalizing on the increased sensitivity afforded by combining PCR amplification with detection by Southern blot hybridization, it became possible to demonstrate HTLV tax and/or pol proviral sequences in freshly isolated PBMC of most patients with mycosis fungoides. These observations suggest a possible role of the virus in the pathogenesis of CTCL, and may impact on diagnostic and therapeutic measures in the future.

Retroviruses and cutaneous T-cell lymphoma

Since the discovery of the first human retrovirus, HTLV-I, and its etiologic role in ATL, the search for a retrovirus and its role in the development and progression of CTCL has been vigorously pursued and debated. Current studies in CTCL have evaluated serum antibodies to retroviral proteins, electron microscopy to identify viruslike particles, and Southern blot analysis and PCR amplification to detect proviral DNA sequences. There have been inconsistent findings within and between a variety of studies, emphasizing the need for critical evaluation of experimental methods and their potential shortcomings. Several interesting observations have included (1) serologic evidence of HTLV-I infection in a small subset of CTCL patients, (2) cloning of a deleted HTLV-I proviral genome from a B-cell line established from the peripheral blood of a CTCL patient, (3) detection of retrovirus in Langerhans cells and B cells, and (4) molecular evidence for the presence of an HTLV-I-like retrovirus. By viewing CTCL as a model of tumor progression, mechanisms by which retroviruses play a role in the development and progression of CTCL are facilitated. Future studies will need to correlate the detection of proviral sequences and the nature of a retroviral infection with specific cell types and stage of disease and determine if these findings demonstrate a causal role in CTCL or a secondary phenomenon due to CTCL-associated immunosuppression. It is likely that new data will be reported between the writing of this article and the time of publication; however, the currently available data reviewed in this article do not provide conclusive evidence that retroviruses play a primary etiologic role in CTCL.

Retinoic acid-induced apoptosis and regression of a refractory Epstein-Barr virus-containing T cell lymphoma expressing multidrug-resistance phenotypes

The virus-associated T cell leukaemias/lymphomas are characterized by a poor prognosis primarily because of the rapid emergence of drug resistance which may lead to failure of subsequent chemotherapy. We report here a case of Epstein-Barr virus-associated T cell lymphoma which relapsed soon after chemotherapy and radiotherapy. The neoplastic cells of the relapsed tumour expressed high levels of multi-drug resistance gene (mdr1)-related P-glycoprotein and glutathione-S-transferase-pi, both of which were absent in the pre-chemotherapy tumour tissues. Empirical treatment with oral 13-cis-retinoic acid (RA) was then given with subsequent complete disappearance of the tumour. The therapeutic effect of RA appears to act through an apoptotic process. In accordance with our previous report of a successful salvage of a refractory Ki-1 large cell lymphoma. RA appears to be a potentially useful drug for some specific type T-cell lymphomas.

Cutaneous manifestations of Epstein-Barr virus-associated T-cell lymphoma

BACKGROUND

In addition to human T-lymphotropic virus (HTLV-I), the Epstein-Barr virus (EBV) has recently been demonstrated to be associated with cutaneous T-cell lymphoma (CTCL).

OBJECTIVE

Our purpose was to investigate characteristic clinicopathologic features of the cutaneous lesions of EBV-associated T-cell malignancies.

METHODS

Clinical records, laboratory data, and histopathologic sections were reviewed. Freshly frozen tumor tissues were immunophenotyped. Southern blot and in situ hybridization studies were performed to detect the EBV genomes.

RESULTS

Ten of 35 CTCL biopsy specimens collected between 1985 and 1992 were found to be EBV-associated. Clonotypic proliferation of EBV genomes was demonstrated in each case, and the atypical T lymphoid cells contained EBV genomes. The cutaneous eruptions of these patients included multiple violaceous papules or nodules, chronic ulcers, and tumors on the trunk or extremities. Three distinct clinicopathologic subgroups could be recognized. The most consistent was the angiocentric T-cell lymphoma or lymphomatoid granulomatosis (type III CTCL) (four cases), presenting with chronic ulcers or violaceous papules. The second group was the T large-cell lymphoma (type II CTCL), Ki-1 antigen (CD30) (positive or negative) (four cases). Three patients with Ki-1- lymphoma had fulminant disease, whereas the remaining Ki-1+ case had a benign course. The third group was the secondary type CTCL (type V CTCL) (two cases), representing systemic EBV-associated T-cell lymphoma. The prognosis was grave. The common features of these EBV-associated CTCLs are resistance to conventional chemotherapy, poor prognosis, and the terminal manifestation of a hemophagocytic syndrome. No EBV genome could be detected in 12 cases of classic CTCL/mycosis fungoides (type I CTCL), or in three cases of HTLV-I-associated adult T-cell lymphoma (type IV CTCL).

CONCLUSION

Three distinct clinicopathologic subtypes of EBV-associated CTCL were recognized, including one additional type of virus-associated CTCL.

Posttransplant cutaneous lymphoma

BACKGROUND

Posttransplant lymphoma is closely associated with Epstein-Barr virus (EBV) infection and appears to have a predilection for extranodal sites. We describe four cases of primary cutaneous posttransplant lymphoma.

OBJECTIVE

Our aim was to determine cell lineage and any possible association with EBV in each case of cutaneous lymphoma.

METHODS

Tumor tissue was examined by light microscopy, immunohistochemistry, nonisotopic in situ hybridization and polymerase chain reaction.

RESULTS

The data were consistent with a diagnosis of EBV-associated cutaneous B-cell lymphoma in three cases and cutaneous T-cell lymphoma not associated with EBV in one case. No patient with B-cell lymphoma had extracutaneous involvement during a mean follow-up of 3.9 years. The patient with cutaneous T-cell lymphoma died of cerebral involvement 9 months after initial presentation.

CONCLUSION

These data suggest a possible role for EBV infection in the origin of cutaneous B-cell lymphoma in immunosuppressed patients.

Examination of cutaneous T-cell lymphoma for human herpesviruses by using the polymerase chain reaction

The etiology of cutaneous T-cell lymphoma remains unknown, although an association with viral infection, in particular certain retroviruses and human herpesviruses, has been suggested. The purpose of this study was to examine skin biopsies of cutaneous T-cell lymphoma for the presence of Epstein-Barr virus, herpes simplex virus type 1 and type 2, and human herpesvirus-6 by using the polymerase chain reaction. Lesional skin biopsies from 30 patients with cutaneous T-cell lymphoma were studied. Control specimens included biopsies from 9 patients with lymphomatoid papulosis and 10 patients with pityriasis lichenoides et varioliformis acuta. DNA extracted from each specimen, as well as from a known positive control for each virus, was examined by using the polymerase chain reaction with viral-specific primers. Each DNA specimen was also amplified with control primers for human beta globin. The specificity of the amplified products was confirmed by Southern analysis. Neither Epstein-Barr virus nor herpes simplex virus was detected in any of the patient specimens examined. Human herpesvirus-6 was detected in one specimen of cutaneous T-cell lymphoma and one specimen of lymphomatoid papulosis. These results do not support a role for any of these herpesviruses in the pathogenesis of cutaneous T-cell lymphoma.

Cutaneous anaplastic T-cell lymphoma in a patient with human immunodeficiency virus infection: detection of Epstein-Barr virus DNA

The Epstein-Barr virus (EBV) genome exists in tumour cells of T-cell lymphomas in non-immunosuppressed patients. We identified EBV-DNA by in situ hybridization in a case of anaplastic T-cell lymphoma associated with acquired immunodeficiency syndrome (AIDS). EBV-DNA has been reported in AIDS-related Hodgkin's disease or B-cell lymphoma, but never in T-cell lymphoma. Although our results suggest that EBV could play a role in the development of these anaplastic T-cell lymphomas, the mechanism of EBV penetration into T-cells remains uncertain.

HTLV-1-associated cutaneous disease: a clinicopathological and molecular study of patients from the U.K

The clinicopathological features of eight patients with cutaneous disease associated with HTLV-1 infection are reviewed. All were U.K. residents of West Indian extraction, and two are currently alive. Disease remained confined to the skin in two patients. Five patients with a cutaneous prodromal phase developed leukaemia after a median duration of 124 months (3 months-21 years), and in one of these combination chemotherapy produced a sustained clinical remission for 20 months. Two patients developed cutaneous disease after remission of their leukaemia. Cutaneous lesions were heterogeneous and included localized papules, a generalized papulonodular eruption, diffuse and localized erythematous plaques, pompholyx-like lesions on the palms and soles, and tumours. The histology of the skin lesions was also variable, and consisted of a heavy dermal infiltrate with lymphocytes, histiocytes, plasma cells, eosinophils and cytologically atypical mononuclear cells. Epidermotropism was present in biopsies from five patients. Tumour cells with large, densely staining, pleomorphic nuclei, arranged in rows between collagen bundles, were present in the majority of cases. In one patient the infiltrate also consisted of epithelioid cells and multinucleated giant cells. Six cases were classified histologically as pleomorphic T-cell lymphoma, and two as cerebriform or mycosis fungoides type. Molecular studies revealed a clonal T-cell population associated with monoclonal integration of HTLV-1 provirus in tissue DNA from six patients. In two patients HTLV-1 integration was established retrospectively using enzymatic in vitro amplification of a specific HTLV-1 po1 gene sequence in DNA extracted from paraffin-embedded sections. This study indicates that the clinical and pathological features of HTLV-1-associated cutaneous disease are diverse. Patients may have disease confined to the skin for prolonged periods, either at presentation or following clinical relapse--cutaneous adult T-cell lymphoma. Molecular techniques allow distinction from other types of cutaneous T-cell lymphoma, and provide an opportunity for retrospective studies of archival material.

Karyotypic derivation of H9 cell line expressing human immunodeficiency virus susceptibility

BACKGROUND

The T-cell lymphoma HUT78 cell line and the H9 clone of the CD4-positive HT cell line, derived from HUT78, are known to be genetically identical on the basis of allozyme (allelic isozyme) patterns and DNA fingerprinting, but the chromosome compositions of these cell lines have not been determined. The HT cell line and its H9 clone carry susceptibility to the human immunodeficiency virus (HIV).

PURPOSE

The purpose of this study was to examine specific chromosome changes linking the expression of the HIV susceptibility that is unique to H9 cells by characterizing the karyotypes of the HUT78 and the H9 cell lines, by comparing chromosome differences between these lines, and by evaluating the relationships between them.

METHODS

Air-dried chromosome slides were prepared, and the fast Giemsa-trypsin method was used to delineate G-bands. The numerical distribution of chromosomes from the two cell lines was determined, and complete chromosome analysis in 47 HUT78 metaphases and 21 H9 metaphases with discernible G-banding was used to specify the modal karyotypes of each cell line.

RESULTS

Both cell lines had complex karyotypes that contained 47%-65% structurally modified marker chromosomes. The distribution of numbers of chromosomes in HUT78 cultures was broad. There were two distinct modal numbers of chromosomes at 42 and 43 and at 73, resulting from the presence of three actively growing sublines: two hypodiploid (1s) sublines (HUT78/1sA and HUT78/1sB) and a hypertriploid (2s) subline (HUT78/2s), respectively. HUT78/1sA and HUT78/1sB differed by five reciprocal chromosome replacements, and HUT78/2s had double copies of most of the chromosomes in 1s cells. H9 and HUT78/2s had had 21 matching markers, 10 of which were paired; contained 21 chromosomes with the same number of copies; consistently lacked eight homologous normal chromosomes; and showed close modal numbers of chromosomes at 69 and 73, respectively.

CONCLUSIONS

Derivation of the 2s subline from the 1s subline by polyploidization is apparent. All lines apparently had the same progenitor cell population, and HUT78/2s represents an intermediate linking HUT78/1s to H9.

IMPLICATIONS

These data should be useful for studying specific chromosome changes linking the expression of the HIV susceptibility unique to H9 cells. Karyologic studies such as those presented here can provide data (a) to clearly identify the clonal cell population of a subline, (b) to examine relationships among sublines of the same progenitor, and (c) to provide a clue that may link a subtle chromosome change to a phenotypic expression.

T-cell leukemia-lymphoma and mycosis fungoides

Notable efforts have been made to relate aspects of the cell biology of T cells to the pathology, diagnosis, and treatment T-cell neoplasms. In particular, the application of molecular biologic tools to these areas has already allowed the generation of patient-specific markers for disease. A case can be made that a knowledge of the distinctive natural history of T-cell neoplasms should influence choices of treatment. Additional insights into the relevance of the human T-cell leukemia-lymphoma virus family to human disease have been recorded, and an important association of cutaneous T-cell lymphoproliferative disorders with human immunodeficiency virus infection has been documented.

Cutaneous angiocentric T-cell lymphoma associated with Epstein-Barr virus

BACKGROUND

Two unusual cases of cutaneous angiocentric T-cell lymphoma were found to be associated with Epstein-Barr virus infection.

OBJECTIVE

The objective was to study the clinical course and the response of the disease to conventional chemotherapy.

METHODS

Histologic specimens from both patients were studied. Clonal proliferation was assessed by Southern blot hybridization.

RESULTS

The disease in both patients was rapidly progressive and responded poorly to aggressive treatment. Biopsy specimens showed infiltration of atypical lymphoid cells with angiocentricity and angiodestruction, which probably resulted in the observed tissue necrosis. Clonal proliferation of Epstein-Barr virus DNA was detected in tissue from primary skin lesions and disseminated nasal lesions.

CONCLUSION

Epstein-Barr virus-associated angiocentric T-cell lymphoma in our patients was characterized by an aggressive course and resistance to conventional chemotherapy. A search for Epstein-Barr virus and the human T-lymphotropic virus should be performed in patients with atypical features of cutaneous T-cell lymphoma.