bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytokeratin profiles of the thymus and thymomas: histogenetic correlations and proposal for a histological classification of thymomas
Authors: Kuo
Published: March 2003

Aims

Since cytokeratins (CKs) are useful as differentiation markers for histogenetic and classification studies, we investigated the CK profiles of the thymus and thymomas in an attempt to understand the histogenetic correlation and to propose a histological classification.

Methods and results

Nine thymuses and 34 thymomas were immunostained for various CKs of different molecular weights and involucrin. Based on cytomorphology and histoarchitecture, thymomas were classified into spindle cell (SC), small polygonal cell (SPC), mixed, organoid, large polygonal cell (LPC) and squamoid (SQ) thymomas for compiling CK profiles. The thymus was shown to comprise four epithelial compartments, each expressing a different CK profile. Different histological types of thymoma expressed different CK profiles. By correlating the CK profiles of the thymus and thymoma, SPC, SC and LPC thymomas appeared to be related to subcapsular, medullary and cortical cells, respectively. Organoid thymoma recapitulated the structure and CK profile of the normal thymus, while SQ thymoma acquired additional squamous type CK. The applicability and usefulness of the proposed histological classification were evaluated on 147 thymomas by correlating the results with their invasive behaviour. One hundred and thirty‐nine cases (95%) could be classified and different histological types correlated strongly with their invasive behaviour.

Conclusions

The thymus is a complex epithelial organ composed of heterogeneous cell types giving rise to various related histological types of thymoma. The results of the CK profile study supports the proposed histological classification, which is pathologically applicable and clinically useful in correlating with invasiveness. This cytomorphological classification, supported by the CK expression patterns, is comparable to Müller‐Hermelink classification and the new WHO histological classification except that a separate group of SPC thymoma expressing only CK14 and CK19 was identified and separated from mixed thymoma.
c‐mos immunoreactivity is an indicator of good prognosis in lung cancer
Authors: Athanasiou A , Gorgoulis V G , Zacharatos P , Mariatos G , Kotsinas A , Liloglou T , Karameris A , Foukas P , Manolis E N , Field J K , Kittas C
Published: March 2003

Aims

Reports concerning the expression of cytoplasmic components of the mitogen‐activating protein kinase (MAPK) pathway in lung cancer are limited. One of the molecules participating in this pathway is the product of the c‐mos proto‐oncogene. In vitro investigations, in somatic cells, have shown that c‐mos expression has opposing effects on cell cycle progression suggesting that it may represent an important determinant of aberrant cell function. In this study we analysed, by immunohistochemical means, its status in a series of lung carcinomas and correlated the findings with clinicopathological parameters and survival of the patients.

Methods and results

Sixty cases of lung carcinomas were included in the study. These comprised 52 non‐small (NSCLCs) and eight small cell lung carcinomas (SCLCs). Sections from the carcinomas were immunostained with the polyclonal anti‐c‐mos antibody P‐19. Specificity was tested by using the appropriate control peptide and control cell lines. Expression was observed in 63% of the cases, with NSCLCs showing higher reactivity (67%) than SCLCs (37.5%). Staining was observed mainly to the cytoplasm and membranes of the cancerous cells, but some nuclei reacted as well. An intratumour heterogeneous immunoreactivity was noticed. The most interesting and unexpected finding was that c‐mos positive staining was associated with better recurrence‐free survival in our series, regardless of histological type (P = 0.035). Furthermore, favourable disease‐related and recurrence‐free survival was observed in the SqC group with c‐mos immunoreactivity (P < 0.001).

Conclusions

c‐mos proto‐oncogene is expressed in a significant proportion of lung carcinomas and may play a role in its development. The fact that its expression is associated with a relatively good prognosis may be indicative of a negative impact on tumour growth.
Lymphomatous features of aggressive NK cell leukaemia/lymphoma with massive necrosis, haemophagocytosis and EB virus infection
Authors: Mori N , Yamashita Y , Tsuzuki T , Nakayama A , Nakazawa M , Hasegawa Y , Kojima H , Nagasawa T
Published: March 2003

Aims

: Aggressive natural killer (NK) cell leukaemia will be categorized as a distinct entity in the new WHO classification of malignant lymphomas. However, its non‐leukaemic features remain unclear. We therefore investigated the morphological and immunophenotypic features of this lymphoma.

Methods and results

: Four cases with aggressive NK cell lymphoma were morphologically and immunohistochemically studied. All cases followed an aggressive course with death occurring within about 3 months of initial presentation. In these cases, the neoplastic cells disseminated throughout systemic lymph nodes and invaded various tissues and organs. The lymphoma cells were large cells showing nuclear irregularity and a pattern of sinusoidal invasion in lymph nodes. Apoptosis and coagulation necrosis were both frequently observed. Haemophagocytosis was observed in all cases. Neoplastic cells in paraffin‐embedded tissue specimens from these patients had CD3(CD3ε)+ CD56(123C3)+ granzyme+ TIA‐1+ EBERT+ CD43(MT1)− CD45RO(UCHL‐1)− CD57(Leu7)− CD20(L26)− phenotypes. In the two cases where tissue was available for immunohistochemical study in frozen sections, neoplastic cells showed CD56(Leu19)+ perforin+ Fas ligand(FasL)+ CD2(Leu5b)− CD3(Leu4)− CD4(Leu3)− CD5(Leu1)− CD7(Leu9)− CD8(Leu2)−βF1− TCRδ1− phenotypes. CD16(Leu11b) was positive in one case.

Conclusions

: Natural killer cell lymphomas appear to represent a non‐leukaemic counterpart of aggressive natural killer cell leukaemia, a relationship similar to that in adult T‐cell leukaemia/lymphoma. Awareness and diagnosis of this aggressive lymphoma is important because of its fulminant course.
Gastric or intestinal phenotypic expression in the carcinomas and background mucosa of multiple early gastric carcinomas
Authors: Kabashima A , Yao T , Sugimachi K , Tsuneyoshi M
Published: March 2003

The differences in phenotypic expression between multiple early gastric carcinomas (EGCs) and solitary EGCs were evaluated in this study.

Fifty‐three cases (53 lesions) of solitary EGCs and 50 cases (112 lesions) of multiple EGCs were studied. According to the classification of intestinal metaplasia, the phenotypes of carcinomas and background mucosa were classified into four categories—complete intestinal type, incomplete intestinal type, gastric type and unclassified type—based on the combination of expression of CD10 (small intestinal brush border), MUC2 (intestinal goblet cell), HGM (gastric foveolar epithelium) and Con A (gastric pyloric glands). The incidence of gastric‐type carcinomas (48%) and the incidence of incomplete intestinal‐type background mucosa (75%) among the multiple EGCs was higher than among the solitary EGCs. There was a significant difference in distribution of phenotypic expression of carcinomas and background mucosa between the solitary EGCs and the multiple EGCs, the latter being associated with incomplete intestinal metaplasia.

Both the carcinomas and the background mucosa of multiple EGCs have an unstable status, since they more commonly possess the hybrid phenotype of the stomach and the small intestine than does solitary EGC. Such instability is considered to contribute to a high neoplastic potential and the multiple occurrence of carcinomas.
Follicular dendritic cell sarcoma of the colon mimicking stromal tumour
Authors: Chang K‐C , Jin Y‐T , Chen F‐F , Su I‐J
Published: March 2003

Follicular dendritic cell tumours are very rare neoplasms that often occur in lymph nodes. We report here a case in the colon, a hitherto unreported site, in a 37‐year‐old female. The differentiation from gastrointestinal stromal tumour is emphasized.

The tumour was tan, elastic and solid with surface ulceration. Microscopically, it was composed of oval to spindle tumour cells with syncytial cytoplasm arranged in fascicular and whorled patterns. There were many infiltrating lymphocytes. The histological appearance resembled gastrointestinal stromal tumour, thymoma or meningioma. Distinct from the stromal tumour, the lymph node was also involved by the tumour. Immunohistochemically, the tumour cells were positive for CD21, CD35 and CD68, but negative for cytokeratin, CD34, smooth muscle actin, desmin, S100 protein, epithelial membrane antigen, leukocyte common antigen, HMB‐45 and c‐kit. In‐situ hybridization study was negative for Epstein–Barr virus RNA sequences. Ultrastructurally, the tumour cells possessed cytoplasmic processes joined by desmosomes.

This entity should be considered in the list of differential diagnoses for gastrointestinal stromal tumour. The lymph node metastasis and immunohistochemical features are of value for identification of this rare neoplasm.
mRNA expression of urokinase and plasminogen activator inhibitor‐1 in human crescentic glomerulonephritis
Authors: Lee H S , Park S Y , Moon K C , Hong H K , Song C Y , Hong S Y
Published: March 2003

mRNA expression of urokinase and plasminogen activator inhibitor‐1 in human crescentic glomerulonephritis

Aims: Weak staining for urokinase‐plasminogen activator (uPA), tissue type plasminogen activator (tPA), or plasminogen activator inhibitor‐1 (PAI‐1) confined to crescents has been described in a few cases of severe crescentic glomerulonephritis. We evaluated the molecular mechanism by which these proteins are increased or induced within crescents.

Methods and results: We examined uPA, tPA and PAI‐1 mRNA expression in 12 renal biopsies with crescentic glomerulonephritis, and in six control renal biopsies with no detectable abnormalities by RNA in‐situ hybridization. The expressions of uPA, tPA and PAI‐1 proteins were also assessed by immunofluorescence. To better determine the cellular origin of uPA and PAI‐1 transcripts, CD68 protein was studied by immunohistochemistry on the same sections on which in‐situ hybridization had been performed. In controls, there were very low level signals of uPA and PAI‐1 mRNAs in a few glomerular epithelial cells (GECs). Specific signals of uPA and PAI‐1 mRNAs were detected in the cells forming crescents in all the cases with crescentic glomerulonephritis. However, weak expression of mRNA for tPA was detected in two cases only. Immunostaining for uPA and PAI‐1 was positive in some but not all, cases of crescentic glomerulonephritis. A double‐labelling study showed that the signal for PAI‐1 and uPA mRNAs was mainly in CD68− cells.

Conclusions: Local accumulation of uPA or PAI‐1 in crescents is associated with enhanced mRNA expression of these proteins. The up‐regulation of PAI‐1 mRNA by GECs, in particular, could play a major role in the formation of persistent fibrin deposits and progression of the lesions in crescents. Whether up‐regulation of uPA is an epiphenomenon or plays a pathogenic role in the formation of crescents remains to be clarified.
Familial multiple gastrointestinal stromal tumours with associated abnormalities of the myenteric plexus layer and skeinoid fibres
Authors: Handra‐Luca A , Fléjou J‐F , Molas G , Sauvanet A , Belghiti J , Degott C , Terris B
Published: March 2003

Familial multiple gastrointestinal stromal tumours with associated abnormalities of the myenteric plexus layer and skeinoid fibres

Aims: Multiple familial gastrointestinal stromal tumours are rare. We report the third family with two cases of multiple gastrointestinal stromal tumours showing skeinoid fibres. Associated abnormalities of the myenteric plexus layer are described and new hypotheses for the histogenesis of gastrointestinal stromal tumours are formulated.

Methods and results: Multiple gastrointestinal stromal tumours developed in the duodenum and proximal jejunum were removed from mother and son. No history of a specific syndrome or of mastocytosis was known. Light microscopy revealed typical gastrointestinal stromal tumours with skeinoid fibres. An unusual abnormality of the myenteric plexus layer, showing a diffuse spindle cell hyperplasia, was noted in the macroscopically normal digestive wall. No abnormalities of the ganglion cells were associated. Tumours and the spindle cell hyperplasia showed similar morphological and immunohistochemical features with expression of CD34 and CD117 antigens. Follow‐up revealed recurrences in the mother.

Conclusion: The morphological characteristics of these two cases of familial gastrointestinal stromal tumours and of the associated abnormalities of the myenteric plexus layer, help to better explain the histogenesis of multiple familial gastrointestinal stromal tumours. The hyperplasia of the myenteric plexus could be considered a risk factor for recurrent tumours.
DNA topoisomerase IIα expression correlates with cell proliferation but not with recurrence in intracranial meningiomas
Authors: Konstantinidou A E , Patsouris E , Korkolopoulou P , Kavantzas N , Mahera H , Davaris P
Published: March 2003

DNA topoisomerase IIα expression correlates with cell proliferation but not with recurrence in intracranial meningiomas

Aims: To assess the value of topoisomerase IIα (TopoIIα) as a novel proliferation‐associated molecule, by correlating its immunohistochemical expression with Ki67 (MIB‐1), cell proliferating cell nuclear antigen (PCNA) and mitotic index in meningiomas. Furthermore, to investigate its relation to standard clinicopathological parameters and patients’ outcome.

Methods and results: This retrospective study comprised a consecutive series of 57 patients with primary intracranial benign and atypical meningiomas. Six tumours recurred (10.5%) following complete surgical resection, within a follow‐up period ranging from 21 to 108 months (median 60 months). Archival formalin‐fixed paraffin‐embedded sections were stained with standard immunohistochemical methods. The lower proliferation indices were obtained with TopoIIα and the higher ones with PCNA. TopoIIα labelling index (LI) ranged from 0.1% to 10% (median 0.5%) and, along with Ki67 and PCNA LI, increased with malignancy grade (P=0.049, P=0.045 and P < 0.001, respectively), displaying though a significant overlapping between grades. A significant positive correlation was shown between TopoIIα and Ki67 (P < 0.001) or PCNA (P=0.032). In univariate and multivariate survival analysis, TopoIIα failed to predict meningioma recurrence and did not affect disease‐free survival. Only tumour size and Ki67 LI provided significant prognostic information in this regard.

Conclusions: TopoIIα expression may be useful as a novel proliferation marker in meningiomas, presenting several advantages over the markers currently in use, notably providing a better estimate of the number of cycling cells and a more uniform nuclear staining pattern. However, it fails to discriminate between benign and atypical neoplasms and does not provide prognostic information beyond that obtained by Ki67.
Lobular endocervical glandular hyperplasia is a metaplastic process with a pyloric gland phenotype
Authors: Mikami Y , Hata S , Melamed J , Fujiwara K , Manabe T
Published: March 2003

Lobular endocervical glandular hyperplasia is a metaplastic process with a pyloric gland phenotype

Aims: Lobular endocervical glandular hyperplasia of the uterine cervix is a rare pseudoneoplastic lesion of the uterine cervix, described recently. Our aim was to characterize the clinicopathological and immunohistochemical features of lobular endocervical glandular hyperplasia, to elucidate its pyloric gland phenotype, and to distinguish it from adenoma malignum of the uterine cervix.

Methods and results: Nine cases of lobular endocervical glandular hyperplasia were studied histologically and immunohistochemically. The average age of the nine patients was 48.8 years (range 38–64 years). Six cases were found incidentally, whereas in three cases a watery vaginal discharge and imaging studies suggested adenoma malignum preoperatively. Microscopically, lobular endocervical glandular hyperplasia ranged from 1 mm to 20 mm (mean 6.8 mm) in the largest horizontal extent and 1 mm to 10 mm (mean 3.9 mm) in depth, and was characterized by lobular arrangements of small glands composed of low columnar cells with pale eosinophilic cytoplasm and bland nuclei. Three cases showed a pseudo‐invasive growth. Intracytoplasmic mucin was predominantly PAS‐positive, and seven cases showed immunoreactivity for M‐GGMC‐1, an antibody that reacts with pyloric gland‐type mucin. Only focal and faint reactivity for CEA was seen, and ER was negative in all cases. The cytokeratin profile was CK7+/20– in all cases, in keeping with their Müllerian derivation. All three lesions examined contained chromogranin‐positive endocrine cells. After surgery all patients are well without recurrent disease (mean follow‐up was 48.4 months).

Conclusions: Lobular endocervical glandular hyperplasia is a morphologically distinct pseudoneoplastic glandular lesion, which has unique phenotypic characteristics shared by pyloric glands of the stomach. Although most are found incidentally, some cases may show clinical and radiological features resembling those of adenoma malignum.
Malignant mesenchymoma of the uterus, arising in a leiomyoma
Authors: Bakker M A den , Hegt V Noordhoek , Sleddens H B F M , Nuijten A S M , Dinjens W N M
Published: March 2003

Malignant mesenchymoma of the uterus, arising in a leiomyoma

Aims: To document and find evidence for the rare occurrence of malignant progression of a benign uterine leiomyoma with divergent mesenchymal differentiation. In a 54‐year‐old female a large pedunculated tumour was encountered which had suddenly increased in size and had apparently arisen at the site of a subserosal uterine leiomyoma first described 19 years earlier. The tumour seemed histologically diverse in its composition. The possibility of malignant progression of the benign leiomyoma with divergent mesenchymal differentiation was entertained.

Methods and results: In the resected tumour, smooth muscle, osseous and adipose components were identified and these were assessed using recognized histological criteria of malignancy. In addition to a benign smooth muscle component, malignant leiomyosarcomatous tissue was seen in addition to a malignant osseous component and a malignant adipose component. The tumour thus met the criteria of a malignant mesenchymoma. The relationship of the different components of the tumour was analysed by immunohistochemistry and with molecular loss of heterozygosity (LOH) analysis. In the osseous and leiomyosarcomatous components a similar LOH pattern was observed. The adipose component showed a distinct LOH pattern. Retention of smooth muscle differentiation in the osseous component was demonstrated by desmin immunostaining.

Conclusion: Malignant transformation of benign uterine leiomyoma may rarely occur. Mesenchymal stem cells underlying these tumours may show divergent mesenchymal differentiation.
The TSC‐2 product tuberin is expressed in lymphangioleiomyomatosis and angiomyolipoma
Authors: Johnson S R , Clelland C A , Ronan J , Tattersfield A E , Knox A J
Published: March 2003

The TSC‐2 product tuberin is expressed in lymphangioleiomyomatosis and angiomyolipoma

Aims: Lymphangioleiomyomatosis is categorized by proliferation of abnormal smooth muscle cells (LAM cells) in the lungs and lymphatics and the presence of angiomyolipomas. Recently mutations in the tuberous sclerosis complex‐2 gene (TSC‐2) have been described in LAM cells and angiomyolipomas. The TSC‐2 protein tuberin is a tumour suppressor and its loss may result in cellular proliferation. We used immunohistochemistry to test the hypothesis that uncontrolled cellular proliferation in lymphangioleiomyomatosis is the result of reduced tuberin protein expression.

Methods and results: Tissue from normal lung, normal kidney, lymphangioleiomyomatosis and angiomyolipomas was immunostained with three separate anti‐tuberin antibodies. Tuberin staining in normal tissues was similar to that previously described. Surprisingly, tuberin was strongly expressed in the LAM cells of all cases of lymphangioleiomyomatosis and angiomyolipoma at a greater level than in normal smooth muscle cells. The perivascular cells of angiomyolipomas, however, did not stain for tuberin.

Conclusions: Our results suggest that a loss of tuberin protein in LAM cells is not the cause of the cellular proliferation seen in lymphangioleiomyomatosis. Lymphangioleiomyomatosis may result either from the expression of a mutant tuberin with abnormal function, as a result of mutations in functionally related proteins, or from more than one mechanism.
Lymph nodes in gastric B‐cell lymphoma: pattern of involvement and early histological changes
Authors: Ko Y H , Han J J , Noh J H , Ree H J
Published: March 2003

Lymph nodes in gastric B‐cell lymphoma: pattern of involvement and early histological changes

Aims: This study aims to analyse the histological pattern of nodal involvement in gastric B‐cell lymphoma and to detect early involvement of the lymph nodes.

Methods and results: Histological findings of 37 resected primary gastric lymphomas with 1313 regional lymph nodes were analysed. The primary tumour was classified into four groups: MALT lymphoma, MALT lymphoma with a minor large B‐cell lymphoma (<20%), large B‐cell lymphoma with MALT lymphoma, and large B‐cell lymphoma without MALT lymphoma. Histological patterns of nodal involvement were divided into sinusoidal, subsinusoidal/marginal, follicular, and diffuse patterns. Semi‐nested polymerase chain reaction (PCR) analysis for IgH gene rearrangement was performed. Nodal involvement was found in 2/13 (15%) MALT lymphomas, 5/6 (83%) MALT lymphomas with a minor large B‐cell lymphoma, 9/12 (75%) large B‐cell lymphomas with MALT lymphoma, and 6/6 (100%) large B‐cell lymphomas without MALT lymphoma. The MALT lymphoma and MALT lymphoma with a minor large B‐cell lymphoma showed a predominantly sinusoidal and subsinusoidal pattern, whereas diffuse pattern predominated in large B‐cell lymphomas without MALT lymphoma and large B‐cell lymphomas with MALT lymphoma. The follicular pattern was least common, being observed in 10.2% of large B‐cell lymphomas without MALT lymphoma and large B‐cell lymphomas with MALT lymphoma. Sinusoidal obliteration with permeation of small monocytoid cells into subsinusoidal zone is a characteristic finding suggesting early nodal involvement of MALT lymphoma.

Conclusions: Histological patterns of nodal involvement in gastric B‐cell lymphoma vary according to the histological grade. Immunostaining for CD20 with or without PCR analysis for IgH gene rearrangement would be a useful ancillary method to confirm lymphomatous involvement.
Expression of intercellular adhesion molecule‐1 and vascular cell adhesion molecule‐1 in human crescentic glomerulonephritis
Authors: Moon K C , Park S Y , Kim H W , Hong H K , Lee H S
Published: March 2003

Expression of intercellular adhesion molecule‐1 and vascular cell adhesion molecule‐1 in human crescentic glomerulonephritis

Aims:  In glomerulonephritis, intercellular adhesion molecule‐1 (ICAM‐1) and vascular cell adhesion molecule‐1 (VCAM‐1) may play important roles in the formation of crescents. These studies are designed to evaluate the expression patterns of ICAM‐1 and VCAM‐1 in human crescentic glomerulonephritis and to determine the cellular origin of adhesion molecules in the crescentic lesions.

Methods and results:  We examined the expression of ICAM‐1 and VCAM‐1 proteins in renal biopsies with cellular (n=7), fibrocellular (n=9) or fibrous (n=4) crescentic glomerulonephritis, and six controls by immunohistochemistry. mRNA expression of ICAM‐1 and VCAM‐1 was further evaluated by RNA in‐situ hybridization. Cytokeratin or CD68 immunohistochemistry was performed on the same sections, where in‐situ hybridization had been carried out. In cellular crescents, ICAM‐1 and VCAM‐1 proteins were over‐expressed to a similar extent. Of the three types of crescents, the extent of ICAM‐1 immunopositivity was the greatest in the cellular crescents and decreased towards the fibrous crescents (P < 0.05). Yet the extent of VCAM‐1 immunoreactivity was not different between the types. Fibrous crescents still contained some epithelial cells and showed only VCAM‐1 expression. In the glomeruli with cellular or fibrocellular crescents, the extent of ICAM‐1 immunopositivity in the glomerular tufts was significantly larger than that of VCAM‐1 (P < 0.05). In an in‐situ hybridization study, the mRNA expression patterns of ICAM‐1 and VCAM‐1 paralleled their protein expressions. A double‐labelling study showed that the signal for ICAM‐1 and VCAM‐1 mRNAs was mainly present in cytokeratin‐positive and CD68‐negative cells in the crescentic lesions.

Conclusions:  These results suggest that glomerular parietal epithelial cells in cellular crescents up‐regulate both ICAM‐1 and VCAM‐1, and that some epithelial cells retained in fibrous crescents persistently over‐express VCAM‐1, but not ICAM‐1. They also suggest that ICAM‐1 is involved in early leucocyte recruitment into glomeruli in crescentic glomerulonephritis.
Follicular baso‐squamous melanocytic tumour of the skin
Authors: Riccioni L , Cenacchi G , Ragazzini T , Collina G
Published: March 2003

Aims: We describe a previously unrecognized pigmented tumour of the skin and suggest a possible relationship with the follicular bulb.

Methods and results: A pigmented epithelial neoplasm clinically simulating a malignant melanoma of the skin was present in a 92‐year‐old woman, on her left leg. It was composed of three cell types: squamous cells with trichilemmal keratinization, basaloid cells and dendritic melanocytes. The presence of three cell types was confirmed by immunohistochemistry and electron microscopy.

Conclusions: The tumour showed differentiation towards the hair follicular bulb and the descriptive term of follicular baso‐squamous melanocytic tumour is suggested.
Th1 cytokine mRNA expression dominates in the skin‐draining lymph nodes of C57BL/6 mice following vaccination with irradiated Schistosoma mansoni cercariae, but is down‐regulated upon challenge infection
Authors: Betts  , Wilson
Published: March 2003

Vaccination of C57BL/6 mice with irradiated cercariae of Schistosoma mansoni results in the induction of high levels of immunity to subsequent infection. The events occurring in the lymph nodes draining the exposure site have been analysed ex vivo by reverse transcription–polymerase chain reaction (RT‐PCR) and the timing of cytokine gene expression following exposure has been established. After vaccination, spatial separation of the T‐helper type 1 (Th1) and Th2 responses was evident, with interferon‐γ (IFN‐γ), interleukin‐2 (IL‐2) and IL‐12 mRNA peaking earlier than mRNA for IL‐4, IL‐5 and IL‐10. In contrast to the profiles observed post‐vaccination, following challenge the IL‐4 mRNA was predominant in the draining lymph nodes, with IFN‐γ message levels barely detectable above the naïve level. These observations are confirmed by the analysis of IL‐4 and IFN‐γ mRNA using competitive PCR. From these studies it is clear that irradiated cercariae are more able to promote a protective Th1 response, with normal parasites eliciting higher IL‐4 and IL‐5 expression upon both primary and secondary stimulation.
Synovial fibroblasts as target cells for staphylococcal enterotoxin‐induced T‐cell cytotoxicity
Authors: Kraft  , Filsinger  , KRÄmer  , Kabelitz  , HÄnsch  , Schoels
Published: March 2003

Rheumatoid arthritis (RA) is a chronic autoimmune disease of unknown aetiology. Recently, superantigens have been implied in the pathogenesis of RA. Superantigens activate a large fraction of T cells leading to the production of cytokines and proliferation. In addition, superantigens direct cellular cytotoxicity towards major histocompatibility complex (MHC) class II‐expressing cells. There is now increasing evidence that cytotoxic T cells may be involved in the pathogenesis of RA. In the inflamed synovia class II‐positive synovial fibroblasts (SFC) are found. In the present study it was tested whether MHC class II‐positive SFC serve as target cells for superantigen‐induced cellular cytotoxicity. SFC were stimulated with interferon‐γ to express class II antigens, then they were cultivated in the presence of CD4‐positive T cells with or without staphylococcal enterotoxins (SE). Cytotoxicity of T cells was measured as release of lactate dehydrogenase from SFC. Specific cytotoxicity was only found in the presence of class II‐positive SFC depending on the dose of SE. Maximum lysis was seen after 20 hr. T‐cell cytotoxicity was inhibited by antibodies to MHC class II antigens. The data suggest that class II‐positive SFC not only function as accessory cells for SE‐mediated T‐cell proliferation and interleukin‐2 production but may also be the targets of superantigen‐mediated cellular cytotoxicity.
Group B streptococci persist inside macrophages
Authors: Cornacchione  , Scaringi  , Fettucciari  , Rosati  , Sabatini  , Orefici  , Von Hunolstein  , Modesti  , Modica  , Minelli  , Marconi
Published: March 2003

Group B streptococci (GBS) are an important cause of neonatal sepsis, pneumonia and meningitis. In the early phase of infection, macrophages and polymorphonuclear cells (PMN) are the first immune cells that interact with GBS. In this in vitro study, to gain insight into GBS–macrophage interaction in the absence of type‐specific antibodies, we examined the features of GBS survival in thioglycollate‐elicited murine peritoneal macrophages and the effect of GBS on the protein kinase C (PKC)‐dependent transduction pathway. Our results demonstrate that type Ia GBS, strain 090 (GBS‐Ia) and type III GBS strain COH 31r/s (GBS‐III), after in vitro phagocytosis survive and persist intracellularly in macrophages for up to 24 and 48 hr, respectively. However, macrophage activation by interferon‐γ (IFN‐γ) and lipopolysaccharide from Escherichia coli (LPS) caused a significant reduction in the time of intracellular persistence. Macrophage activation by IFN‐γ and LPS seems to be a multifactorial event involving multiple intracellular signal pathways also including PKC. Since PKC is one of the components in the signal network leading to macrophage activation and an important target for several intracellular micro‐organisms, we wondered whether PKC could have a role in intracellular GBS survival. Both PKC depletion by treatment with phorbol 12‐myristate 13‐acetate (PMA) for 18 hr and PKC inhibition by Calphostin C rendered macrophages more permissive for the intracellular GBS survival. Furthermore, GBS‐infected macrophages were unable to respond to PMA and LPS, activators of PKC, by inducing antimicrobial activity. The ability of GBS to impair PKC‐dependent cell signalling was also demonstrated by the reduced c‐fos gene expression in GBS‐infected macrophages with respect to control macrophages, after LPS stimulation. In conclusion, our results indicate that GBS survive in macrophages and impairment of PKC signal transduction contributes to their intracellular survival.
Nitric oxide produced in the lungs of mice immunized with the radiation‐attenuated schistosome vaccine is not the major agent causing challenge parasite elimination
Authors: Coulson  , Smythies  , Betts  , Mabbott  , Sternberg  , Wei  , Liew  , Wilson
Published: March 2003

Mice vaccinated with radiation‐attenuated cercariae of Schistosoma mansoni exhibit high levels of protection against a challenge with normal larvae. The immune effector mechanism, which operates against schistosomula in the lungs, requires CD4+ T cells capable of producing interferon‐γ (IFN‐γ). This cytokine can stimulate production of nitric oxide (NO), via its ability to up‐regulate inducible nitric oxide synthase (iNOS). We have therefore evaluated the potential role of NO in the effector mechanism operating in vaccinated mice. Evidence for the production of NO in the lungs of such animals was obtained from assays on antigen‐stimulated airway cell cultures. Enhanced levels of NO, compared with those in cultures from control mice, were detected both after vaccination and after challenge; elevated levels of iNOS mRNA were also present in whole lung after challenge. However, administration of an iNOS inhibitor to vaccinated mice after percutaneous challenge did not significantly increase the worm burden. Furthermore, when mice with a disrupted iNOS gene were vaccinated they showed a highly significant level of protection. Although NO from activated macrophages can mediate cytotoxic killing of newly transformed schistosomula in vitro, we have demonstrated that the addition of erythrocytes to these larvicidal assays abolishes its effects. We interpret this to mean that once migrating schistosomula enter the bloodstream they will be protected against the cytotoxic actions of NO. Our data thus provide little evidence to implicate NO as a major component of the pulmonary effector response to S. mansoni in vaccinated mice.
Resistance ranking of some common inbred mouse strains to Mycobacterium tuberculosis and relationship to major histocompatibility complex haplotype and Nramp1 genotype
Authors: MEDINA  , NORTH
Published: March 2003

Six common inbred strains of mice and their F1 hybrids were examined for resistance to infection with the H37Rv strain of Mycobacterium tuberculosis. According to survival times after inoculation of 105 CFU intravenously (i.v.), the mice could be classified as being either highly susceptible (CBA, DBA/2, C3H, 129/SvJ) or highly resistant (BALB/c and C57BL/6). F1 hybrids of susceptible and resistant strains were resistant. Although an examination of a limited number of H‐2 congenic strains showed that the H‐2k haplotype could confer susceptibility on a resistant strain, it was evident that non‐major histocompatibility complex (MHC) genes were much more important. Resistant strains all possessed the susceptibility allele of the anti‐microbial resistance gene, Nramp1. Results obtained with selected strains infected with 102 CFU of M. tuberculosis by aerosol agreed with the results obtained with mice infected i.v. The size of the bacterial inoculum was important in distinguishing between resistant and susceptible strains, in that a 107 inoculum overcame the resistance advantage of one strain over another.
Immunoglobulin VH gene sequence analysis of spontaneous murine immunoglobulin‐secreting B‐cell tumours with clinical features of human disease
Authors: ZHU  , VAN ARKEL  , KING  , VAN MEIRVENNE  , DE GREEF  , THIELEMANS  , RADL  , STEVENSON
Published: March 2003

The 5T series of multiple myelomas (MM) and Waldenstrsöm’s macroglobulinaemia‐like lymphomas (WM), which developed spontaneously in ageing mice of the C57BL/KaLwRij strain, shows clinical and biological features that closely resemble their corresponding human diseases. In order to compare the patterns of somatic mutation in VH genes of mouse tumours with those of human counterparts, we have determined and analysed sequences of immunoglobulin VH genes in five cases of murine MM, two of WM and one of biclonal benign monoclonal gammopathy (BMG). Four of five MM and 2/2 WM cases used VH genes of the large J558 family; one MM used a gene of the VGAM3.8 family, and both clones of the BMG used genes of the 36‐60 family. N‐region insertions were observed in all cases, but D‐segment genes were only identified in 6/9 cases, which were all from the D‐SP family and translated in reading frame 3. Compared with human MM, in which the VH genes have been found to be consistently hypermutated (mean%±SD=8·8±3·2), the degree of somatic mutation in the murine tumours was significantly lower (mean%±SD=2·9±2·3). There was no significant evidence of clustering of replacement mutations in complementarity determining regions (CDR), a feature considered to be characteristic of antigen‐selected sequences. However, one clone of the biclonal BMG case showed intraclonal variation, a feature described in some cases of human BMG. These results indicate that murine VH genes in mature tumours differ from human counterparts in the level and distribution of somatic mutations, but support the concept that BMG may be distinct from MM.
Inhibition of an established allergic response to ovalbumin in BALB/c mice by killed Mycobacterium vaccae
Authors: WANG  , ROOK
Published: March 2003

Allergic disorders are mediated by T lymphocytes secreting T helper 2 (Th2) cytokines, interleukin‐4 (IL‐4) and interleukin‐5 (IL‐5), resulting in high levels of serum immunoglobulin E (IgE) and recruitment of eosinophils. One of the treatment strategies is to downregulate the Th2 component by inducing a T helper 1 (Th1) response to the relevant allergen, because Th1 and Th2 cytokines are thought to be mutually antagonistic. In this study, we examined the effects of Mycobacterium vaccae, a potent inducer of Th1 immunity, on allergic responses in a murine model. A single injection of M. vaccae into ovalbumin (OVA)‐preimmunized BALB/c mice suppressed serum IgE over a wide dose range (107, 108 or 109M. vaccae). Further experiments, using 107M. vaccae injected twice, showed that this treatment inhibited not only serum IgE, but also the potential for ovalbumin‐induced IL‐5 production by spleen cells. This non‐specific ability of a mycobacterium to decrease Th2 activity, even when not presented together with the allergen, is in agreement with recent epidemiological studies on the impact of bacillus Calmette–Guérin (BCG) vaccination, and of other potent Th1 stimuli, on the incidence of atopy. The suppression of serum IgE and allergen‐specific IL‐5 synthesis by M. vaccae suggest that this organism is likely to have clinical application in the immunotherapy of allergy.
Antibodies with idiotypic and anti‐idiotypic reactivity (epibodies) in conventional immune responses to dinitrophenylated carriers
Authors: MUHUMUZA  , SEGRE†  , SEGRE
Published: March 2003

A number of monoclonal antibodies were derived from the spleen cells of dinitropheryl (DNP)‐immunized mice. Both T‐dependent and T‐independent carriers were used, and the intensity and length of immunization were varied. It was found that some of the antibodies had only idiotypic (Ab1) reactivity, while others had both idiotypic (Ab1) and anti‐idiotypic (Ab2) reactivity. Among the latter antibodies some molecules reacted specifically with DNP and with the combining site of anti‐DNP antibodies (epibodies), while others bound DNP and anti‐DNP Abs as well as a variety of unrelated antigens (polyreactive antibodies). The proportion of the three types of antibodies (antigen‐specific, epibodies and polyreactive antibodies) varied with the nature of the carrier, the intensity of the immunization, and the length of the immunization process. Further characterization of the epibodies, which were predominant in the secondary response to DNP‐keyhole limpet haemocyanin (KLH), showed that both Ab1 and Ab2 reactivities were inhibited by both soluble ligands (DNP and anti‐DNP), indicating that the specific combining site of the monoclonal antibodies (mAbs) (and/or of the rabbit anti‐DNP antibody in the case of Ab2) was involved in both activities. Both Ab1 and Ab2 reactivities were removed by absorption of the mAbs with either immobilized DNP or immobilized rabbit anti‐DNP. The mAbs were capable of binding themselves as well as to other mAbs with the same characteristics. The affinity constants of several mAbs for both the DNP and anti‐DNP ligands were determined.
Lymphocyte trafficking: CD4 T cells with a ‘memory’ phenotype (CD45RC−) freely cross lymph node high endothelial venules in vivo
Authors: SPARSHOTT  , BELL
Published: March 2003

Antigen encounter not only induces a change in surface expression of CD45RC isoforms in the rat from a high (CD45RC+) to a low molecular weight molecule (CD45RC−),but also stimulates changes in expression of adhesion molecules that regulate CD4 T‐cell migration. T cells with an activated or ‘memory’ phenotype (CD45RC−) are thought to enter lymph nodes almost exclusively via afferent lymphatics whereas T cells in a resting state (CD45RC+) migrate across high endothelial venules (HEV). The present study monitored the rapid recirculation from blood to lymph of allotype‐marked CD45RC T‐cell subsets. Surprisingly, we found that CD45RC− CD4 T cells entered the thoracic duct slightly faster and reached peak numbers 3 hr earlier (18 hr) than did the CD45RC+ subset. To determine whether the entrance of CD45RC+ and RC− subsets was restricted to HEV and afferent lymphatics, respectively, recirculation of CD4 T cells was monitored in mesenteric lymphadenectomized (MLNx) rats (on healing the intestinal afferent lymphatics are joined directly to the thoracic duct), or in recipients that had had the mesenteric lymph node (MLN) acutely (2–3 hr) deafferentized (entry would be restricted to HEV). In these studies CD45RC− CD4 T cells entered the MLN across HEV on an equal basis with T cells expressing a CD45RC+ phenotype. Contrary to currently held dogma the results showed that, in vivo, CD4 T cells with a memory phenotype freely enter lymph nodes (LN) across HEV as well as via afferent lymphatics.
Expression of CD69 activation marker by endometrial granulated lymphocytes throughout the menstrual cycle and in early pregnancy
Authors: VASSILIADOU N. , BULMER J. N.
Published: March 2003

Flow cytometry studies of first‐trimester normal human decidua have proposed that a proportion of endometrial granulated lymphocytes (eGL), the predominant leucocyte population in early human pregnancy, co‐express CD69. The purpose of this study was to investigate CD69 expression by immunohistochemistry throughout the menstrual cycle and in first‐trimester human decidua and to determine whether CD69 expression by eGL is an in vivo characteristic or whether the antigen is acquired in vitro after tissue disaggregation and cell purification. Single immunoenzymatic and double immunofluorescence labelling of tissue sections, supplemented with double immunoenzymatic staining of purified eGL and flow cytometry, indicated that eGL do not co‐express CD69 in situ but that they acquire the molecule in vitro after cell purification and culture.
Eosinophilia, IgE production, and cytokine production by lung T cells in surface CD4‐deficient mutant mice infected with Toxocara canis
Authors: TAKAMOTO  , WANG  , WATANABE  , MATSUZAWA  , NARIUCHI  , SUGANE
Published: March 2003

Mutant mice deficient in CD4+ T cells and their normal and heterozygous littermates were infected with Toxocara canis, and compared for eosinophilia, total and Toxocara‐specific immunoglobulin E (IgE) production, and in vitro cytokine production by lung cells. The numbers of eosinophils in the peripheral blood of normal and heterozygous mice peaked on days 10 and 21, although mutant mice showed eosinophilia with a peak on day 10. This indicates that the first peak on day 10 is CD4 independent and the second peak is CD4 dependent. Before infection, the levels of total IgE had no significant difference among the three groups of mice. Total and Toxocara‐specific IgE in all genotypes of mice increased after infection, and was the highest in normal mice and the lowest in mutant mice. In vitro production of interleukin (IL)‐5 and IL‐4 by total lung cells was the highest in normal mice and the lowest in mutant mice. CD4+ and CD4− CD8− T lymphocytes, but not CD8+ T lymphocytes produced IL‐5 and IL‐4 when incubated with anti‐CD3 monoclonal antibody (mAb) and lung‐adherent cells. These results indicated that IL‐5 and IL‐4 were produced mainly by CD4+ cells and partly by CD4− CD8− cells, but not by CD8+ cells. In addition, cytokine production by CD4+ cells was affected by the number of CD4 molecules on their surface.
Differential effects of protein kinase C inhibitors on fibronectin‐induced interleukin‐β gene transcription, protein synthesis and secretion in human monocytic cells
Authors: RITZENTHALER  , ROMAN
Published: March 2003

Human monocytic cells express interleukin‐1β (IL‐1β) when stimulated with the extracellular matrix glycoprotein, fibronectin (FN). Protein kinase C (PKC) activation is considered important for this process; however, the metabolic steps at which PKC acts upon to mediate the FN‐induced IL‐1β response remain unclear. We performed an analysis of the mechanisms by which two PKC inhibitors, Calphostin C and Staurosporine, prevent the FN‐induced IL‐1β response. Both inhibitors blocked the secretion of IL‐1β protein into the media of peripheral blood mononuclear cells exposed to FN. Immunoprecipitation analysis revealed that under these circumstances, Calphostin C inhibited the production of IL‐1β protein, whereas Staurosporine allowed protein production, but inhibited its secretion. To determine the mechanisms responsible for these differences, we turned to human U937 promonocytic cells. U937 cells transfected with the human full‐length IL‐1β promoter connected to a luciferase reporter gene were submitted to transcription assays, Northern blotting, and DNA electrophoresis mobility gel shift assays. These studies revealed that Calphostin C inhibited the nuclear translocation of the transcription factor activator protein‐1 (AP‐1) which is considered necessary for FN induction of IL‐1β gene transcription, and prevented the transcription of the IL‐1β gene. In contrast, Staurosporine alone induced AP‐1 translocation and stimulation of the gene. Overall, our data indicate that Calphostin C prevents the transcription of the IL‐1β gene thereby inhibiting protein synthesis. Based on the high specificity of this compound for PKC, we conclude that PKC is necessary for FN‐induced IL‐1β protein production. In contrast, Staurosporine prevented secretion of IL‐1β by unknown mechanisms.
MIP‐3α, MIP‐3β and fractalkine induce the locomotion and the mobilization of intracellular calcium, and activate the heterotrimeric G proteins in human natural killer cells
Authors: AL‐AOUKATY  , ROLSTAD  , GIAID  , MAGHAZACHI
Published: March 2003

We demonstrate here that the CC chemokines macrophage inflammatory protein‐3α (MIP‐3α), macrophage inflammatory protein‐3β (MIP‐3β) and the CX3C chemokine fractalkine induce the chemotaxis of interleukin‐2 (IL‐2)‐activated natural killer (IANK) cells. In addition, these chemokines enhance the binding of [γ‐35S]guanine triphosphate ([γ‐35S]GTP) to IANK cell membranes, suggesting that receptors for these chemokines are G protein‐coupled. Our results show that MIP‐3α receptors are coupled to Go, Gq and Gz, MIP‐3β receptors are coupled to Gi, Gq and Gs, whereas fractalkine receptors are coupled to Gi, and Gz. All three chemokines induced a robust calcium response flux in IANK cells. Cross‐desensitization experiments show that MIP‐3α, MIP‐3β or fractalkine use receptors not shared by each other or by the CC chemokine regulated on activation, normal, T‐cell expressed, and secreted (RANTES), the CXC chemokines stromal‐derived factor‐1α (SDF‐1α) and interferon‐inducible protein‐10 (IP‐10), or the C chemokine lymphotactin.