NETs detection and quantification in paraffin embedded samples using confocal microscopy.

Detection and quantification of Neutrophil Extracellular Traps (NETs) in tissue samples has become a topic of great interest to understand their pathological role in various diseases. We describe a semi-automatic method of visualization and quantification of NETs in paraffin-embedded intracoronary thrombus aspirate samples. This study is based on colocalization of myeloperoxidase (MPO) and citrullinated histone 3 (H3Cit) as hallmark of the presence of NETs. For the analysis we used the confocal immunofluorescence microscopy technology to quantify the number of fields and the total area (in µm2) containing NETs in each thrombus sample. This observer-independent quantification method could be a useful tool to standardize the study of NETs in paraffin-embedded tissues, enabling comparison of results among different laboratories.

Polar Marine Microorganisms and Climate Change.

The large diversity of marine microorganisms harboured by oceans plays an important role in planet sustainability by driving globally important biogeochemical cycles; all primary and most secondary production in the oceans is performed by microorganisms. The largest part of the planet is covered by cold environments; consequently, cold-adapted microorganisms have crucial functional roles in globally important environmental processes and biogeochemical cycles cold-adapted extremophiles are a remarkable model to shed light on the molecular basis of survival at low temperature. The indigenous populations of Antarctic and Arctic microorganisms are endowed with genetic and physiological traits that allow them to live and effectively compete at the temperatures prevailing in polar regions. Some genes, e.g. glycosyltransferases and glycosylsynthetases involved in the architecture of the cell wall, may have been acquired/retained during evolution of polar strains or lost in tropical strains. This present work focusses on temperature and its role in shaping microbial adaptations; however, in assessing the impacts of climate changes on microbial diversity and biogeochemical cycles in polar oceans, it should not be forgotten that physiological studies need to include the interaction of temperature with other abiotic and biotic factors.

Richter's transformation of chronic lymphocytic leukemia. The possible role of fludarabine and the Epstein-Barr virus in its pathogenesis.

Transformation of CLL into a large cell lymphoma has an incidence of 3-5%. We have studied 101 cases of CLL treated with fludarabine over a 10-year period (1990-2000) and observed a 12% incidence of transformation. In six of 12 patients, transformation was documented within 4 months following treatment with fludarabine. Pathological material, available in nine cases, was investigated for latent EBV by staining for LMP-1 by immunohistochemistry and EBERs-1 and 2 by in situ hybridisation. LMP-1 and EBERs were demonstrated in three of the nine samples. In two cases there was a different pattern of immunoglobulin gene rearrangement in the transformed cells assessed by PCR (FR3 fragment) compared to the original CLL clone. One of these two cases showed evidence of latent EBV. The other seven cases, of which two were EBV positive, showed identical pattern of Ig gene rearrangement in both the CLL and the transformed cells. We suggest that the relatively high incidence of transformation in this series may be due to immunosuppression mainly related to fludarabine, although other agents and prior therapies may have also contributed.

Pathological, immunological, and molecular features of Hodgkin's disease associated with HIV infection. Comparison with ordinary hodgkin's disease.

The aim of the present study was to analyze in a series of 24 HIV-positive Hodgkin's disease (HD) patients the morphological and immunological features, the presence of rearrangements in the immunoglobulin heavy chain (IgH) gene, expression of the Epstein-Barr virus (EBV) latent membrane protein-1 (LMP-1), and the existence of deletions in the intracytoplasmic domain of the LMP-1 gene. The results obtained were compared with those from a parallel series of 56 patients with ordinary HD. Briefly, comparison of the two series showed a predominance of unfavorable histological subtypes in HIV-positive HD patients. The mixed cellularity subtype was more frequent in HIV-positive than in HIV-negative HD patients: the difference in percentage was statistically significant (p = 0.04). Neoplastic cell-rich cases were significantly more frequent (p = 0.40) in HIV patients (59%) than in ordinary HD patients (34%). In 25% of HIV-infected and in 14% of ordinary HD patients, the neoplastic cells were CD20+, a difference that was not statistically representative. Clonal IgH rearrangements were detected in 33% of HIV-infected patients and in 23% of ordinary HD patients, a nonsignificant difference. LMP-1 expression was detected in 100% of HIV-positive patients and in 57% of ordinary HD patients (p = 0.004). A 30-base-pair deletion in the carboxy-terminal domain of the LMP-1 gene was found in 16 of 18 HIV-infected patients (89%), whereas it was identified in only 8 of 25 ordinary HD patients (32%) (p = 0.008). In conclusion, HD in HIV-infected patients as compared with HD in HIV-negative individuals is associated with morphological features of aggressivity, with a higher frequency of neoplastic cells, and with constant LMP-1 expression. The fact that LMP-1 is expressed in all HIV-infected patients suggests that EBV plays an etiological role in the pathogenesis of HIV-associated HD. Furthermore, the presence of EBV strains carrying deletions near the 3' end of the LMP-1 gene in the majority of cases may be related with the morphological and clinical aggressivity of HD in immunocompromised patients.

Cutaneous follicular B-cell lymphoma: description of a series of 18 cases.

The lack of precise and homogeneous criteria for the recognition of primary cutaneous follicular lymphoma has hindered gaining data on the frequency and clinical and molecular features of this entity. In the course of a review of a series of primary cutaneous lymphoma from different Spanish hospitals, we collected a series of 18 cases of primary cutaneous follicular lymphoma and analyzed its clinical, morphologic, and biologic characteristics. In this review only cases with a follicular pattern of growth, germinal center cytology, and restriction to the skin in a minimum follow-up of 6 months have been included. Cases of primary cutaneous follicular lymphoma were characterized by the expression of classic markers of the germinal center, such as bcl6, CD10, and the presence of aggregates of follicular dendritic cells. They frequently express bcl2 protein, although classical t(14;18) was not found in any of the cases analyzed. Analysis of the bcl6 noncoding first exon showed somatic mutations in two of four cases analyzed, as would be expected in lymphoma deriving from the germinal center. Clinically, most cases showed initial involvement of the head and neck, with relapses in eight cases (involving the skin in five cases, both skin and lymph node in two cases, and lymph node in one case). No death attributable to the tumor was recorded. These data seem to imply that follicular lymphoma may present initially in the skin, lacking the characteristic t(14;18) and having a relatively indolent course. Recognition of these tumors and elucidation of their molecular alterations could lead to properly adapted staging and treatment protocols for these patients.

Utility of flow cytometric analysis of mast cells in the diagnosis and classification of adult mastocytosis.

The diagnosis of bone marrow (BM) involvement in mastocytosis has mainly been based on conventional histology. Nevertheless, in recent years, three major methodological advances have been made: the measurement of serum tryptase levels, the immunohistochemical assessment of mast cell (MC) tryptase, and the immunophenotypical characterization of BMMC using flow cytometry (FCM). The most characteristic immunophenotypic feature in mastocytosis is the coexpression of CD2 and CD25 antigens, which are never present in normal BMMC and constitute a phenotypic hallmark of BMMC in adult mastocytosis. Such observations would support the need to include the immunophenotypic analysis of MC in the diagnosis of mastocytosis.

Pleural effusion as first sign of extramedullary plasmacytoma.

A patient with mediastinal EP with extension to pleural spaces and subsequent pleural effusion is described. The finding of many plasma cells in pleural fluid led to diagnosis. Similar histologic findings such as multiple myeloma and immunoblastic lymphoma were ruled out by clinical approach and immunochemistry, respectively. This pleural effusion represents the first case described caused by EP.

Metastatic carcinoma of the prostate presenting as a superior vena cava syndrome.

A 75-year-old patient presented with a superior vena cava syndrome (SVCS) lasting 3 years. A prostatic carcinoma was found and a supraclavicular lymph node biopsy specimen disclosed metastasis of the prostatic carcinoma. Antiandrogen and luteinizing hormone-releasing hormone analogue therapy produced a marked improvement. Prostatic carcinoma, although a very rare cause, must be considered in the diagnosis of cases of SVCS with a protracted course, since it is a treatable disease.

Clinicoepidemiologic characteristics, prognostic factors, and survival analysis of patients coinfected with human immunodeficiency virus and Leishmania in an area of Madrid, Spain.

From 1987 to 1995, a retrospective case study was conducted at the Ramon y Cajal Hospital in Madrid, Spain, a public teaching hospital with 1,100 beds, to determine the clinicoepidemiologic characteristics, survival, and prognostic factors of patients with visceral leishmaniasis (VL) and human immunodeficiency virus (HIV) infection. The prevalence of VL in HIV+ patients compared with HIV- patients was studied. Epidemiologic, clinical, and parasitologic characteristics, as well as the effects of treatment, prognosis, and survival in 54 HIV+ patients (90 episodes) with VL were defined. Comparative survival studies among patients with and without acquired immunodeficiency syndrome (AIDS)-defining criteria and multivariate analysis of survival risk factors were performed. The prevalence of VL in patients with AIDS was much higher than in immunocompetent individuals. In spite of a good initial response to treatment for VL, 60.6% of the patients had relapsed by the end of one year. Mortality from the first episode was 18.5%, and 24% died in the first month after diagnosis of any VL episode. The mean survival of the 29 patients who died was 10.27 months. Survival in patients with and without AIDS at the time of the first episode of VL was compared at 30 months: 53.7% versus 20.5% (P = 0.00149). We found no significant difference (P = 0.24) in the survival of HIV+ patients who had died of VL without AIDS at the time of the first episode of VL compared with those of a control group of 413 dead patients with AIDS without VL. A diagnosis of AIDS at the time of the first episode of VL and thrombocytopenia were the only risk factors found related to survival. We conclude that in AIDS patients, VL is a recurrent disease that is highly prevalent and whose clinical course is modified by HIV.

Deletions within the epstein-barr virus latent membrane protein-1 oncogene in adult ordinary, HIV-associated and paediatric Hodgkin's disease.

The aims of this study were the following: a) to perform Epstein-Barr virus (EBV) strain type assignment in three groups of Hodgkin's disease(HD): adult ordinary (39 cases), paediatric (24 cases), and HIV-associated (30 cases) and to compare the prevalence of type 1 and type 2 in each of the groups with that existing in two reference populations made up of 50 adults and 39 children; b) to assess the frequency of latent membrane protein-1 (LMP-1) 30-base pair (bp) deletions in the HD groups and in the healthy controls; and c) to relate the presence of LMP-1 deletions with EBV type. Type 2 EBV was observed in 12.8% of ordinary HD, in 26.7% of HIV-associated HD, in 25% of paediatric HD, in 4% of adult controls, and in none of the healthy children. The existence of double infections by type 1 and 2 EBV was also observed in 5.1% of ordinary HD, in 6.7% of HIV-associated HD, and in 10% of adult controls. The 30-bp deletion was identified overall in 33.3% of ordinary HD, in 83.3% of HIV-positive HD, 79.2% of paediatric HD, 34.7% of adult controls, and 36.4% of healthy children. Statistical analysis showed a significant association of the deleted strains with HD occurring in HIV-positive patients (P= 0.00003) and childhood HD (P= 0.006). On the other hand, the prevalence of the 30-bp deletion in the adult ordinary HD group reflects the prevalence of the deletion in the general population. Co-infections by deleted and non-deleted EBV strains were detected in 12.8% of ordinary HD, in 33.3% of HIV-associated HD, in 50% of paediatric HD, in 26.5% of adult controls, and in 27.3% of healthy children. Concerning the relationship between the deletion and the EBV typing, 26% of type 1 specimens carried the 30-bp deletion in an isolated manner compared with 64.7% of type 2. The statistical analysis showed that the deletion was associated with type 2 strains when coinfections were excluded and only the cases in which the deletion appeared alone were considered (P=0.003).

Other cancers in patients with gastric MALT lymphoma.

Patients with Hodgkin's disease and nodal non-Hodgkin's lymphomas seem to have an excess risk for other cancers. A high incidence of other cancers has also been found in some series of patients with gastric MALT lymphomas. In a series of 136 patients with gastric MALT lymphomas the occurrence and features of other cancers have been described. In order to evaluate their occurrence statistically (excluding skin cancers) standard incidence ratios (SRI) have been calculated, using the incidence rates of a Cancer Registry in Spain as a reference. A Cox's multivariate proportional hazard model was fitted in order to evaluate the influence of age, sex, histological grade and treatment with chemotherapy or chemotherapy plus radiotherapy in the development of other non-skin cancers occurring after the diagnosis of MALT lymphoma. Other cancers were detected in 16 of the 136 patients (11.7%); the other cancer was detected prior to MALT gastric lymphoma in 6 patients (4.41%), concomitantly in 4 (2.9%) and after diagnosis of the lymphoma in 6 (4.41%). Other cancers occurred in 14.4% of the male and in 8.3% of the female patients; in 12% of the patients with low grade and in 11% of the patients with high grade lymphomas. Of the 6 cancers that occurred after diagnosis of the gastric lymphoma, 3 did in the 80 patients (3.7%) that had been treated with chemotherapy, 1 in the 3 cases (33%) treated with chemotherapy and radiotherapy and 2 in the 53 patients (3.7%) who had not received chemotherapy or radiotherapy. The most frequent other cancers were lymphoid neoplasms and gastric carcinoma. There was not an excess of other cancers in the whole cohort or in the sex or histological grade strata. There was an excess close to significance (SIR =2.59; 95% CI:0.98-6.88) in the patients under 50 years of age. In the Cox's analysis, age, sex, histological grade and treatment did not influence the occurrence of other cancers after the diagnosis of lymphoma. In conclusion, in patients with gastric MALT lymphoma other cancers also occur. An excess incidence was not demonstrated, although it may exist in patients under 50 years. Of special importance is the occurrence of gastric cancer that appears concomitantly or after gastric lymphoma.

Epstein-Barr virus-latent membrane protein 1 expression has a favorable influence in the outcome of patients with Hodgkin's Disease treated with chemotherapy.

The effect of molecular factors in the outcome of Hodgkin's Disease (HD) is being currently studied. In a previous series of HD, including patients treated only with radiotherapy and patients treated with chemotherapy (with or without radiotherapy), we found that a high proliferation index had an adverse influence in overall survival (OS) and in the achievement of a complete remission (CR). Loss of Rb expression also had an adverse prognostic influence in achievement of CR. On the other hand LMP1-EBV expression had a favorable influence for OS. The expression of other molecular factors, p53, bcl2 and CD15 did not show prognostic influence. In the present paper we have studied the effect of these molecular variables in 110 patients, of the previous series who had been treated with chemotherapy. A retrospective study was performed in these 110 patients with HD treated with chemotherapy (ABVD or variants, 62%, or regimes not containing adriamycin, 38%) with or without adjutant radiotherapy, collected at the 11 centers belonging to the Spanish Collaborative Group for the Study of Hodgkin's Disease. The prognostic value of clinical variables and the expression of p53, bcl2, CD15, Rb, LMP 1-EBV and proliferative fraction demonstrated with sensitive immunohistochemical methods were studied. Cox's multivariate analysis was performed to assess their influence in failure-free survival (FFS) and OS. A multivariate logistic regression analysis was performed for studying the effect of the variables in the achievement of a CR. Of the clinical variables, only advanced stage (III/IV) had a significant independent adverse influence in FFS, in OS and in the achievement of CR and advanced age in OS. Of the molecular variables, LMP1-EBV had an independent and strong favorable influence in FFS, in OS and in the achievement of CR. Rb expression had a modest favorable influence in CR. The rest of the molecular variables had no independent influence on the outcome of the disease. In conclusion these results confirm the favorable prognostic value of LMP1-EBV expression in the subset of patients with HD treated with chemotherapy.

Evaluation of the international index in the prognosis of high grade gastric malt lymphoma.

The International Prognostic Index identifies four risk groups with different survival rates in aggressive non-Hodgkin's lymphoma. We have studied whether a slight modification of this index has prognostic significance in high grade gastric B-cell MALT lymphoma. In 53 patients with high grade gastric B-cell MALT lymphoma the following survival factors were investigated: age over or under 60 years, sex, B symptoms, more than one extranodal site of involvement other than the stomach, serum LDH levels, performance status, stage I/IIE1/IIE2 v.s. stage III/IV, treatment with surgery, chemotherapy or both modalities together and the four risk groups as defined by the Modified International Prognostic Index (MIPI). A multivariate Cox's test was used to evaluate the independent prognostic significance on survival of all the above variables. Advanced stage (III/IV) and involvement of more than one extranodal site not including stomach were the only variables influencing survival. The MIPI was not sufficient to separate groups with significant differences in survival or to stratify prognostic groups. In this series, the MIPI did not show prognostic significance in high grade gastric B-cell MALT lymphoma.

Thyroid-infiltrating B lymphocytes in Graves' disease are related to marginal zone and memory B cell compartments.

B lymphocytes that infiltrate the thyroid (Thy-B cells) in Graves' patients appear to be implicated in the pathophysiology of this disorder. The goal of the present study was to examine the nature of these Thy-B cells. To this end, Thy-B lymphocytes were isolated from surgical thyroidal samples, and their phenotype was determined by using mouse monoclonal antibodies (mAb) directed against a wide variety of surface markers, followed by flow cytometry multicolor analysis. The results show that most Thy-B cells (approximately 60%) exhibited IgM(+) IgD(low to -) surface immunoglobulin (Ig) profile, whereas the minor cell fraction (approximately 30%) consisted of switched IgG(+) memory B lymphocytes. Thy-B cells expressed low levels of CD5, CD23, and CD62L, which distinguished them from the resting B-cell pool, the major B-cell subset in the blood. In addition, they lacked CD38, CD10, and CD71, characteristic molecules for the germinal center B lymphocytes. In addition, Thy-B lymphocytes showed peculiar patterns both of adhesion molecules (CD62L(-), CD44(intermediate)), and of activation molecules (CD69(+), CD80(+), and, in part, CD95(+)). Taken together, these results suggest that the Thy-B lymphocyte subset consists of a combination of IgM(+) B cells resembling marginal zone B lymphocytes, and isotype-switched memory B cells.

Mesangial deposits of IgM in patients with the nephrotic syndrome.

Kidney biopsies from fourteen patients with the nephrotic syndrome were studied by light, immunofluorescence and electron microscopy. Morphologically, all cases showed moderate diffuse mesangial cell proliferation. In all cases, immunofluorescent microscopy demonstrated diffuse and generalized deposits of IgM as the sole or predominant immunoglobulin. Electron microscopic examination showed electron dense deposits localized in the mesangium in seven cases. One nephrotic patient experienced spontaneous remission and eight others were steroid responsive. Only one of the five steroid resistant patients treated with chlorambucil showed clinical remission. Five steroid responsive patients relapsed. At present, four patients are healthy, having not relapsed for the past two years. Although deposits of IgM may be related to the renal pathology in cases of the nephrotic syndrome, immunofluorescence findings do not seem to be sufficiently consistent or characteristic to justify a possible subclassification of the idiopathic nephrotic syndrome.

Mesangial proliferative glomerulonephritis with unusual intramembranous granular dense deposits.

We have studied two patients with histories of upper respiratory tract infection. Hematuria and proteinuria were the presenting renal symptoms in one patients and an acute nephritic syndrome in the other. Serological findings disclosed depression of total hemolytic complement activity with low levels of C3 and the presence of C3Nef activity. Light microscopy showed diffuse mesangial cell proliferation. By immunofluorescence, diffuse deposits of C3 were found in the glomeruli. Ultrastructural studies revealed segmental thickening of the glomerular basement membrane due to the deposition of granular electron-dense deposits in a laminar pattern. We suggest that our cases may represent a variant of hypocomplementemic glomerulonephritis or perhaps the early stages of dense deposit disease.

Lymphoepithelioma-like carcinoma of the uterine cervix: a case report studied by in situ hybridization and polymerase chain reaction for Epstein-Barr virus.

Lymphoepithelioma-like carcinomas have been reported outside the nasopharynx in many sites, including the uterine cervix. The association with the Epstein-Barr virus in the latter site is still controversial. To date, Epstein-Barr virus genome has only been demonstrated in Asian patients. We report a case of lymphoepithelioma-like carcinoma of the uterine cervix in a white woman in whom the Epstein-Barr virus infection was tested for by in situ hybridization and polymerase chain reaction. The results of both techniques were negative. Our case and a review of the literature support the contention that cervical lymphoepithelioma-like carcinoma is not associated with Epstein-Barr virus infection in non-Asian patients.

Infrequent expression of protein p53 in epidermotropic variants of cutaneous T-cell lymphoma.

Although diverse types of lymphomas have been examined for immunohistochemical detection of p53 protein, little information is available with regard to p53 protein expression in CTCL. We analyzed cutaneous biopsy specimens of 22 patients with the diagnoses of mycosis fungoides or Sézary syndrome with polyclonal rabbit anti-p53 antiserum CM-1. Staining of neoplastic cells was observed only in two patients with advanced disease. Overexpression of p53 protein does not seem to be a major feature of either mycosis fungoides or Sézary syndrome.

Association of body cavity-based lymphoma and human herpesvirus 8 in an HIV-seronegative male. Report of a case with immunocytochemical and molecular studies.

BACKGROUND: Recently lymphomas arising primarily in serosal surfaces have been found in patients with advanced acquired immunodeficiency syndrome (AIDS), but they very rarely seem to occur in human immunodeficiency virus (HIV)-negative patients. Studies on a subset of these lymphomas suggested that they represent a distinct entity associated with Kaposi's sarcoma-associated herpesvirus or human herpesvirus 8 (HHV-8). CASE: An 83-year-old, HIV-negative male was admitted to the hospital with a massive pleural effusion. Abdominal and chest computed tomographic scanning was normal. Cytologic analysis of the pleural effusion revealed a large cell, non-Hodgkin's lymphoma. Polymerase chain reaction analyses on genomic DNA from the pleural effusion demonstrated the presence of HHV-8 sequences in the absence of Epstein-Barr virus. CONCLUSION: It is possible and advantageous to diagnose body cavity-based lymphoma with a combination of cytologic, immunocytochemical and molecular studies of the pleural effusion in conjunction with clinical and radiographic information.