[Cancer of the cervix uteri: analysis of the cost-benefit and efficacy of opportunistic screening versus organized screening]

Cervical cancer is the fourth cancer in women. It is the first malignancy for which mass population screening has been demonstrated to significantly reduce the mortality due to this disease. In Belgium, the mortality associated to cervical cancer decreased from 6 to 4 per 100,000 women-years from 1955-1959 to 1985-1989. European recommendations regarding cervical cancer screening are to perform a cervical smear each three years in women aged 25 to 65 years. In Belgium, while the Flemish region has decided to organize the cervical cancer screening according to the European recommendations, the screening in the French part of the country is essentially opportunistic. In this short review, the cost/benefit of the organized screening versus the opportunistic screening is discussed.

Organotypic culture of HPV-transformed keratinocytes: a model for testing lymphocyte infiltration of (pre)neoplastic lesions of the uterine cervix

The aim of our study was to establish the relevance of an in vitro model for analysing the ability of human lymphocytes to infiltrate human papillomavirus (HPV)-associated (pre)neoplastic lesions of the uterine cervix. To mimic these lesions, we have used the organotypic raft culture of HPV-transformed keratinocytes (SiHa). The SiHa organotypic raft culture was co-cultured with resting or prestimulated (IL-2 or IL-2+anti-CD3 mAb) allogeneic peripheral blood mononuclear cells (PBMC) for 24 and 72 h. The majority of infiltrating cells were T lymphocytes. Occasional NK cells were also identified. The stimulation with IL-2+anti-CD3 mAb induced the highest number of infiltrating cells, with the maximum lymphocyte infiltration observed after 24 h of co-culture. The lymphocyte infiltration was associated with an increased number of apoptotic cells in the organotypic cultures. The ability of PBMC and purified T cell and NK cell populations to lyse HPV-transformed keratinocytes was also investigated on monolayer cultures. As expected in an allogenic model, the highest cytotoxicity was mediated by NK cells activated by IL-2 or IL-2+anti-CD3 mAb. The cytotoxic activity of T cells was weak but, interestingly, increased in the presence of phytohaemagglutinin A (PHA), assuming that T cells were able to kill HPV-infected keratinocytes when a bridge between T cells and keratinocytes was provided. In conclusion, the organotypic culture of HPV-transformed keratinocytes may provide an effective in vitro model for investigating novel T cell-based immunotherapy protocols for the treatment of HPV-associated lesions.

Correlation of T-helper secretory differentiation and types of antigen-presenting cells in squamous intraepithelial lesions of the uterine cervix

This study addressed the notion that the progression of cervical cancer is associated with a T-helper 2 (TH2) immunodeviation by analysing cytokine expression in 60 cervical biopsy specimens, spanning the spectrum from normal cervical tissue to high-grade squamous intraepithelial lesions (SILs). The biopsies were analysed by immunohistochemistry for the expression of TH1 [interleukin-2 (IL2), interferon gamma (IFN gamma)] and of TH2-type cytokines (IL4, IL6). Positive cells were usually observed in the subepithelial connective tissue, where most CD4+ cells were also detected. The density of IL2+ cells was significantly lower in high-grade SILs than in normal tissues taken either from the ectocervix or from the transformation zone. In contrast, significantly higher densities of IL4+ cells and, to a lesser degree, IL6+ cells were found in SIL biopsies compared with histologically normal tissues taken from the adjacent ectocervical region. A significantly higher IL4+/CD4+ cell ratio was also found in high-grade SILs (82 per cent) than in normal cervical biopsies taken from the transformation zone of healthy women showing squamous metaplasia (27 per cent). The elevated density of TH2+ cells in SIL biopsies was associated with both the expression of HLA-DR by keratinocytes and a diminished number of intraepithelial Langerhans' cells (CD1a+). In conclusion, the increased TH2+/CD4+ cell ratio in SIL biopsies suggest the presence, during cervical carcinogenesis, of a TH2 immunodeviation that could participate in the immunoescape of preneoplastic cervical keratinocytes.

[Clinical case of the month. Apropos of a case of adrenal ganglioneuroma: the incidentaloma]

We present a case of adrenal ganglioneuroma discovered during a gastric exploration. We review and discuss the recent literature about "incidentaloma". We propose a reflexion about the investigation of these masses.

Inverse modulation of IL-10 and IL-12 in the blood of women with preneoplastic lesions of the uterine cervix

It has been postulated that an impaired immune response may contribute to the progression of human papillomavirus (HPV)-associated preneoplastic lesions. Based on this hypothesis, we evaluated the cytokine production in the blood of patients with squamous intraepithelial lesions (SIL) of the uterine cervix. The levels of type-1 (interferon-gamma (IFN-gamma) and IL-12) and type-2(IL-4 and IL-10) cytokines were measured in whole blood culture supernatants of patients with low- and high-grade SIL and control women. There was no difference in IL-4 and IFN-gamma levels between patients with SIL and the control group. In contrast, the ratio of IL-12/IL-10 levels was significantly lower in patients with SIL compared with the control group. A lower IL-12/IL-10 ratio in women with SIL was also observed when peripheral blood mononuclear cell (PBMC) culture supernatants and plasma samples were analysed. In patients, neither the lower expression of the CD3epsilon chain nor the higher frequency of HLA-DRB1*1501 expression could be correlated with abnormal cytokine production. These results suggest that a part of the cytokine network, namely IL-10 and IL-12, is perturbed in patients with SIL. A better knowledge of the role of these cytokines in regulating the growth of HPV-associated SIL might have practical implications for the development of vaccines or immunomodulatory strategies in the treatment of cervical cancers.

Efficiency of T cell triggering by anti-CD3 monoclonal antibodies (mAb) with potential usefulness in bispecific mAb generation

T cell triggering can be achieved by monoclonal antibodies (mAbs) specific for the CD3/TcR complex. In the presence of appropriate costimulation and/or progression factors, such triggering permits the generation of effector cells for immunotherapy protocols involving the redirection of T cell lysis against tumor cells by mAbs bispecific for anti-CD3/anti-tumor cells (bs-mAbs). Focusing our analysis on the clinically relevant bs-mAb OC/TR, we found that bs-mAbs generated with the same anti tumor specificity, but two other anti-CD3 mAbs, TR66 and OKT3, have the same and a significantly lower lytic potential, respectively, compared with that of OC/TR. To evaluate the relevance of the anti-CD3 component, we examined several anti-CD3 mAbs with respect to binding parameters and the ability to trigger T lymphocytes. Competitive binding assays suggested that all anti-CD3 mAbs recognized the same or overlapping epitopes, although mAbs BMA030 and OC/TR bound with lower avidity than did alpha CD3 (the bivalent anti-CD3 mAb produced by the hybrid hybridoma OC/TR). TR66 and OKT3, as determined by measurement of the affinity constants. In all lymphocyte populations examined, which included resting peripheral blood mononuclear cells (PBMC), activated PBMC and T cell clones, OKT3, BMA033 and OC/TR failed to mobilize Ca2+ without cross-linking, whereas alpha CD3, in both murine and murine-human chimeric versions, TR66 and BMA030, did not require cross-linking. The ability to induce CD3 modulation was associated in part with the induction of Ca2+ fluxes. Despite the differences in the behavior of these mAbs in triggering the events that precede proliferation, all of them ultimately led to expression of the IL-2 receptor and to proliferation in T cells in the presence of accessory cells. Our data suggest that anti-CD3 mAbs that bind more rapidly (strong Ca2+ mobilizers) and more tightly under physiological conditions are good candidates for retargeting T cells in the bs-mAb clinical application.

Fatal massive liver steatosis--a clinicopathological case report

Hepatic fatty change is a common lesion. Two forms are recognized: micro- and macrovesicular steatosis, the former being much less frequent and more serious than the latter. The case of an alcoholic woman under anticonvulsivant therapy and with medications for a syndrome of inappropriate secretion of antidiuretic hormone (SIADH) who presented with rapidly progressive cholestasis and hepatocellular failure is reported. Massive macro- and micro-vesicular hepatic steatosis was diagnosed at autopsy. The authors review the clinico-pathological features associated with this condition, and causal factors possibly implicated in this case are discussed in regard with currently considered pathophysiological mechanisms.

Expression of the 67 KD laminin receptor in human cervical preneoplastic and neoplastic squamous epithelial lesions: an immunohistochemical study

Interactions of cancer cells with laminin play a critical role during the progression of solid malignant tumours. Increased expression of the 67 kD laminin receptor (67LR), one of the several laminin binding proteins, is associated with the invasive and metastatic capacity of various types of cancer, including breast, colon, ovary, lung, and endometrial carcinoma. In this study, 67LR expression was analysed in a series of cervical biopsy specimens including 16 normal cervical tissues, 36 low-grade squamous intraepithelial lesions (SILs), 24 high-grade SILs, and 11 invasive carcinomas. Detection of the 67LR was performed using immunoperoxidase staining and the monoclonal antibody MLuC5 which specifically recognizes the 67LR. Immunostaining of the 67LR was correlated with human papillomavirus (HPV) type detected by in situ hybridization and with proliferative activity of the lesion determined by immunohistochemistry with the MIB-1 monoclonal antibody, specific for the Ki67 antigen. Increased expression of the 67LR was correlated with the histological severity of the lesions, with the strongest immunoreactivity being found in invasive carcinomas. Significant differences in 67LR expression were found between normal cervical epithelium and high-grade SILs (P < 0.05, non-parametric Mann-Whitney test) or invasive carcinomas (P < 0.001), as well as between low- or high-grade SILs and invasive carcinoma (P < 0.01 and P < 0.05, respectively). Ki67 antigen expression also increased with the severity of the lesions. There was a positive correlation for each type of lesion between expression of the 67LR and of the Ki67 antigen. No specific relationship was found between 67LR or Ki67 antigen immunostaining and HPV type detected in SILs, segregated into low-grade and high-grade lesions. These data add weight to the evidence that increased expression of the 67LR is a consistent, but not sufficient feature of the invasive and metastatic phenotype and suggest that high expression of the 67LR might be associated with both more proliferative and more aggressive cervical (pre)neoplastic lesions.

Peyer's patches in murine AIDS: dissociation between lymphoproliferation and anergy

RadLV-Rs infection induces a murine immunodeficiency syndrome associated with a dramatic enlargement of spleen and lymph nodes. Surprisingly, the lymphoproliferation excludes thymus and Peyer's patches (PP). To understand the cellular interactions underlying lymphoproliferation further, the authors investigated the fate of PP in RadLV-Rs infected mice. The atrophy of PP was mostly due to the depletion of B cells, while the proportion of CD4+ and CD8+ T cells was increased. Nevertheless, B cell phenotype was modified with the emergence of lymphocytes with a low expression of B220 in infected PP. T cells characterized by a memory/activated phenotype in control PP did not undergo phenotypical changes after viral infection (i.e. regarding Thy-1 and CD44 expression). Despite the absence of lymphoproliferation, PP T and B cells displayed altered responses to mitogens in vitro. Finally, alterations of the expression of adhesion molecules and vascular addressins could not explain the atrophy of PP by a reduced homing to this lymphoid site. B cells and T cells from normal PP are clearly different from lymph nodes (LN) lymphocytes. The authors propose that the particular functional state which characterizes PP lymphocytes influences the B cell/T cell crosstalk necessary for RadLV-Rs-induced lymphoproliferation.

Stages in the development of radiation-induced thymic lymphomas in C57 BL/Ka mice: preleukemic cells become progressively resistant to the tumor preventing effects of a bone marrow graft

Fractionated whole body irradiation induces thymic lymphomas in C57 BL/Ka mice after 6-12 months. A graft of normal congenic bone marrow cells immediately after the last irradiation prevents the development of lymphomas by inducing the disappearance of preleukemic cells. When such a graft is performed one month later, it does not inhibit the emergence of tumors. It could be because, one month after irradiation, preleukemic cells become insensitive to the effects of the grafted bone marrow on their leukemogenic potential. To check this hypothesis, we have investigated the capacity of grafted bone marrow cells to prevent the development of lymphomas in mice inoculated with radiation-induced preleukemic cells collected at several time intervals after the completion of the radiation regimen. It was found that the bone marrow graft reduced the incidence of thymic lymphoma at day 2 (10 vs. 43%; p < 0.01) and 10 (39 vs. 86%; p < 0.01) but not at day 15 (64 vs. 80%; NS) or 30 (93 vs. 82%; NS). The inefficacy of the marrow graft was not associated with proliferation of the inoculate in the recipient thymus nor with inhibition by preleukemic cells of thymic repopulation by bone marrow precursors. The data provide evidence that preleukemic cells undergo intrinsic changes which are reflected by the acquisition of resistance to bone marrow grafts.

Subset-specific analysis of calcium fluxes in murine AIDS

Infection of susceptible strains of mice with the Duplan strain of murine leukemia viruses induces a syndrome called MAIDS (murine acquired immunodeficiency syndrome) characterized by immunodeficiency and lymphoproliferation. In addition to a complete refractoriness of most subsets of lymphocytes to mitogen stimulation, the development of phenotypic abnormalities occurs such as the appearance of an abnormal CD4+ T cell subset lacking membranes Thy-1. This study was performed to compare the calcium responses during the early stages of MAIDS (week 9 or earlier) between T cells and B cells and between CD4+Thy-1- and CD4+Thy-1+ T cells. B cells were strikingly less affected than T cells: their baseline [Ca2+]i did not significantly increase, and their calcium response to anti-IgM antibody and concanavalin A (Con A) was partially maintained. In contrast, the response to Con A was completely abolished in T cells. Interestingly, calcium mobilization in response to membrane receptor-independent stimuli such as ionophores and thapsigargin was strongly inhibited in T cells, while no such inhibition was found in B cells. In comparison with their CD4+Thy-1+ counterparts, CD4+Thy-1- T cells had blunted calcium responses in controls, as well as in infected mice. However, CD4+Thy-1+ T cells were also strikingly altered, suggesting that the loss of membrane Thy-1 could be associated with, but not directly responsible for abnormalities of calcium responses in CD4+ T cells from RadLV-Rs-infected mice.

In vivo expression of interleukin-1 beta (IL-1 beta), IL-2, IL-4, IL-6, tumour necrosis factor-alpha and interferon-gamma in the fetal murine thymus

Cytokines are known to play a role in T-cell lymphopoiesis as potent growth or differentiation factors, but many experiments focusing on their role in the thymus have been conducted only in vitro. We have thus used frozen sections obtained from fetal thymuses of normal C57BL 6 mice to investigate by immunohistochemistry the presence of interleukin-1 beta (I4-1 beta), IL-2. IL-4. IL-6. interferon-7 (IFN-7) and tumour necrosis facor-alpha (TNF-alpha). The results reveal that apart from IL-2, which was not detected, all these cytokines display a time-dependent expression pattern in the normal fetal thymus. First, production of IL-4, IL-6 and TNF-alpha is detected around days 13 14; this is followed by a second wave on days 16 17, with a production of IL-1 beta, IL-4 and IL-6, and finally, just before birth (day 19), by a third wave of IL-1 beta, IL-4, IL-6, IFN-7 and TNF-alpha production. This supports the hypothesis that cytokines play a rote in T-cell lymphopoiesis.

Further characterization of cytotoxic T cells generated by short-term culture of human peripheral blood lymphocytes with interleukin-2 and anti-CD3 mAb

In this study we have specifically investigated the participation of T cells in the cytotoxic activity of peripheral blood lymphocytes (PBL) activated by interleukin-2 (IL-2, 50 U/ml) alone or in combination with an anti-CD3 mAb (BMA030, 10 ng/ml, IgG2a). Purified CD3+ T cells, incubated in the presence of the anti-CD3 mAb for 4 days, mediated a cytotoxic activity against HL60 and U937 tumor cell lines. Several findings suggested the involvement of a redirected-cytotoxicity phenomenon, since the lytic process was restricted to target cell lines bearing the high-affinity Fc gamma receptor (Fc gamma RI) and T lymphocytes stimulated by IL-2 alone did not lyse these cell lines. Furthermore, anti-CD3 mAb F(ab')2, anti-CD3 IgG1 (UCHT1), phytohemagglutinin or staphylococcal enterotoxin A did not induce a similar cytotoxic activity in T lymphocytes. The cytotoxic process occurred in the presence of a very low level of anti-CD3 antibodies (in the nanomolar range). The cytotoxic activity of T cells stimulated by IL-2 or by IL-2 + BMA030, against OVCAR-3 cells (MOv18+ ovarian tumor cell line), was also compared in the presence of a bispecific antibody OC/TR, anti-CD3 x MOv18). The stimulation by IL-2 + BMA030 induced approximately a twofold higher cytotoxic activity than IL-2-activated T cells. This could be related to the state of activation of effector cells stimulated by IL-2 + BMA030, since the phenotypic analysis showed an increased proportion of T cells expressing several activation/differentiation markers (CD25, HLA-DR, CD45R0, adhesion molecules). These findings could be applied to the design of therapeutic protocols using anti-CD3 x antitumoral bispecific antibodies.

Prevention of murine radiogenic thymic lymphomas by tumor necrosis factor or by marrow grafting

BACKGROUND

Split-dose irradiation (1.75 Gy given weekly for 4 weeks) of C57BL/Ka mice induces the emergence of preleukemic cells (PLCs). These cells develop into leukemic cells after a latency period of 3-6 months. The survival and transformation of PLCs are dependent on radiation-induced alterations of the thymic epithelium and of resident lymphocyte (i.e., thymocyte) subpopulations in the thymus. PLCs can be eliminated, concomitantly with the restoration of the thymus, by grafting bone marrow cells immediately after the last irradiation. Our hypothesis was that any agent able to restore the thymus after leukemogenic irradiation would exert the same effects as a bone marrow graft. Tumor necrosis factor-alpha (TNF-alpha) is one such possible agent, since it has been shown to modulate some functions of the thymic epithelium and thymocyte subpopulations.

PURPOSE

The goal of this study was to assess the ability of repeated intraperitoneal injections of TNF-alpha to functionally replace bone marrow transplantation in the restoration of normal intrathymic lymphopoiesis and in the prevention of thymic lymphomas in split-dose-irradiated mice.

METHODS

We replaced the bone marrow graft with repeated injections of TNF-alpha (25 000 U/injection) in the split-dose-irradiated (4 x 1.75 Gy) C57BL/Ka mouse model. We analyzed the expression of the cell differentiation markers CD4 and CD8 on thymocytes by flow cytometry. We also studied the thymic environment by isolating thymic nurse cells, the bone marrow prothymocyte activity by analyzing thymic repopulation, and the evolution of PLCs by an in vivo transplantation assay. Local production of TNF-alpha after bone marrow grafting was examined by in situ hybridization. Injections of anti-TNF-alpha antibodies were given to split-dose-irradiated mice to test the effect of neutralizing TNF-alpha in vivo. One-way analysis of variance and Newman-Keuls two-tailed tests were used to test statistical significance.

RESULTS

Multiple injections of TNF-alpha into split-dose-irradiated mice did not influence bone marrow prothymocyte activity but restored thymocyte subpopulations and thymic epithelium, induced the disappearance of PLCs, and prevented the development of lymphomas. Moreover, a bone marrow graft significantly stimulated intrathymic production of TNF-alpha messenger RNA (P<.01), and anti-TNF-alpha antibodies partially inhibited the antilymphomatous effects of bone marrow graft in split-dose-irradiated mice (P<.05).

CONCLUSION

These data strongly suggest that TNF-alpha is a mediator that is involved in the mechanisms by which bone marrow transplantation functions to prevent thymic lymphomas in split-dose-irradiated mice.

IMPLICATIONS

Cytokines might be used in some biological systems, particularly in the hemopoietic system, as a therapeutic agent for the secondary prevention of cancer.

Improved four-color flow cytometry method using fluo-3 and triple immunofluorescence for analysis of intracellular calcium ion ([Ca2+]i) fluxes among mouse lymph node B- and T-lymphocyte subsets

A visible-light, dual-laser, flow cytometric method was developed for the simultaneous analysis of intracellular ionized calcium concentration ([Ca2+]i) and three cell-surface markers (CD4, CD8, and Thy-1.2 antigens) by using the calcium probe fluo-3 and using R-phycoerythrin (PE), peridinin chlorophyll-alpha protein (PerCP), and allophycocyanin (APC) conjugated monoclonal antibodies (MoAbs). This improved method was used in the analysis of [Ca2+]i mobilization upon in vitro stimulation with mitogenic lectins [phytohaemagglutinin (PHA) or concanavalin A (ConA)], anti-CD3 MoAbs, or A23187 calcium ionophore in the heterogeneous lymph node cell populations from healthy C57BL/Ka mice. The present results show that the calcium responses were heterogeneous and dependent on the cellular immunophenotype, not only on lectins or anti-CD3 MoAbs stimulation, but also on the receptor-independent A23187 ionophore stimulation. An in situ fluo-3 calibration method (using A23187 and metabolic poisons in Ca2+ /EGTA buffers with known free calcium concentrations) indicated a resting [Ca2+]i in lymphocytes of 103 +/- 23 nM (mean +/- S.D.) but with significant differences between the [Ca2+]i in B cells and in all of the T-cell subsets (CD4+Thy-1+, CD4+Thy-1-, and CD8+T cells). Both the B cells and the T-cell subsets showed an increase of fluo-3 fluorescence upon in vitro stimulation with ConA or PHA, but the calcium mobilization following lectin stimulation was time delayed in all T-cell subsets. Only the T cells, including the CD4+Thy-1- subset, responded to anti-CD3 MoAbs. The percentage of responding cells upon stimulation with ConA was higher in T cells than in B cells. By contrast, PHA gave a higher response in B cells. After stimulation with different mitogens, [Ca2+]i increased in both CD4+ and CD8+ T-cell subsets. However, the percentage of responding cells was far higher in the CD4+Thy-1+ subset than in the CD4+Thy-1- or the CD8+T-cell subsets. The stimulation with A23187 ionophore induced a higher calcium response in B cells than in T cells. Interestingly, it also induced greater Ca2+ mobilization in CD4+ than in CD8+T cells. These results demonstrate the potential use of fluo-3 simultaneously with three fluorescein (FITC)-compatible fluorochromes. This technique may be useful for investigating the role of the CD4+Thy-1-T cells, a rare subset that is abnormally expanded in a murine acquired immunodeficiency syndrome (murine AIDS).

Assessment of Ki-67 antigen immunostaining in squamous intraepithelial lesions of the uterine cervix. Correlation with the histologic grade and human papillomavirus type

A formalin-fixation and paraffin-processing resistant epitope of Ki-67 cell proliferation-associated antigen was immunohistochemically detected by the MIB-1 monoclonal antibody (Immunotech, Marseille, France) in 25 routinely processed cervical biopsies showing normal squamous epithelium or squamous metaplasia and in 65 cervical intraepithelial lesions (SILs) (44 low grade and 21 high grade SILs) with human papillomavirus (HPV) infection. Expression of Ki-67 antigen was exclusively confined to the parabasal and basal layers of normal and metaplastic epithelium. There was no significant difference of Ki-67 antigen immunostaining between normal cervical biopsies and cases of squamous metaplasia. In SIL specimens, the staining was markedly increased in the parabasal and basal layers and Ki-67-positive cells were also distributed in the intermediate (low grade SIL) or all layers of epithelium (high grade SIL). Statistically significant differences for the density of Ki-67 antigen-labeled cells, which were assessed with an image analysis system, were found in comparisons between normal or metaplastic epithelium and SILs (P < .001) and between low grade SILs and high grade SILs (P < .001). In our series of SILs, HPV 16/18 and 31/33/35/novel types, which were found in both low grade and high grade SILs, were significantly associated with higher densities of Ki-67 antigen-positive cells than HPV 6/11 types that were found exclusively in low grade SILs. There was no significant difference found between the densities of Ki-67 antigen-labeled cells in HPV 16/18-positive and HPV 31/33/35/novel types-positive tissues in our series of SILs taken as a whole or when segregating SILs into low grade and high grade.

Inverse modulation of intraepithelial Langerhans' cells and stromal macrophage/dendrocyte populations in human papillomavirus-associated squamous intraepithelial lesions of the cervix

Ninety-four cervical biopsies from normal tissue to high-grade squamous intraepithelial lesion (SILs) were examined for the presence of intraepithelial Langerhans' cells and subpopulations of stromal macrophages/dendrocytes by immunohistochemistry using anti-S100, -L1, -CD68 and -factor XIIIa antibodies. Human papillomavirus (HPV) detection was performed in all cases by using first a mixture of DNA probes for 14 HPV types commonly found in anogenital biopsies at low stringency conditions (Tm -40 degrees C) and by reanalyzing the tissues at high stringency (Tm -10 degrees C) with HPV 6/11, 16/18 and 31/33/35 biotinylated probe cocktails and individual digoxigenin-labelled probes. SILs and metaplastic tissues were significantly associated with a depletion of S100-positive intraepithelial Langerhans' cells when compared with normal epithelium. In contrast, there was a significant increase in L1-positive stromal macrophages in SIL biopsies compared with normal or metaplastic cervix. A significantly higher density of CD68-positive macrophages was also observed in high-grade SILs compared with normal or metaplastic biopsies and with low-grade SILs. The density of factor XIIIa-positive dendrocytes was found to be higher in SILs compared with metaplastic tissues and in high-grade SILs when compared with normal cervical biopsies. No specific relationship was found between the densities of these cells and the HPV type detected in SILs separated into low grade and high grade. The significance of this inverse modulation of intraepithelial Langerhans' cells and stromal macrophages/dendrocytes in normal and SIL biopsies is discussed in relation to HPV infection and malignant transformation.

Morphological changes of thymus in retrovirus-induced murine acquired immunodeficiency syndrome (MAIDS)

The possible contribution of the thymus in the setting of acquired immunodeficiencies is still questioned. Here we report some new findings regarding a potential involvement of the thymus in mice infected with RadLV-Rs, a viral mixture inducing murine acquired immunodeficiency syndrome (MAIDS). Thymi were sequentially removed, weighted and morphologically analyzed at different time intervals post-infection. Infection with RadLV-Rs led to a decrease in thymus weight mostly apparent from the fourth week. The first changes were seen at the third week as perivascular clusters of B-cells at the cortico-medullary junction. The ensuing process of atrophy mainly involved the cortex, while a mixed population of large T- and B-cells filled the medulla. These observations are discussed with regard to the pathological changes occurring in other lymphoid and non-lymphoid organs, in the context of the lymphoproliferation and immunodeficiency characterizing the disease, and by comparison with other models of retrovirus-induced immunodeficiencies.

Spontaneous and induced apoptosis after whole body radiation exposure: experimental approaches. Observations in radio-induced thymic lymphomagenesis

Radio-induced thymic lymphomagenesis is associated with alterations in the balance between thymocyte subsets and cytokinetic perturbations. The objectives of this work were to investigate whether these alterations are associated with alterations in the basic levels of thymocyte apoptosis. For this purpose, we tested DNA fragmentation by gel electrophoresis, analyzed DNA content by propidium iodide staining of ethanol fixed cells and looked for DNA strand breaks on tissue sections by in situ end labeling. We described an increase of the levels of apoptosis in cultured thymocytes during the preleukemic period, while the basic levels of apoptosis observed in situ are similar in normal and in preleukemic thymuses. We propose that after leukemogenic irradiations, there is an increase of cells wherein the cell suicide program is activated but that environmental thymic factors rescue them from apoptosis. Preleukemic cells could belong to this abnormally surviving population of cells "programmed to die," wherein additional genomic abnormalities would lead to fully neoplastic transformation.

Inhibition of growth of normal and human papillomavirus-transformed keratinocytes in monolayer and organotypic cultures by interferon-gamma and tumor necrosis factor-alpha

The growth response of normal and human papillomavirus (HPV)-transformed cervical keratinocytes to interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha was investigated in monolayer and organotypic raft cultures. The proliferation rates of monolayer cultures were assessed by [3H]TdR incorporation and fluorimetric DNA titration. The growth of keratinocytes in organotypic cultures was estimated by their ability to stratify on collagen rafts and by immunohistochemistry for Ki67 antigen expression. IFN-gamma reduced the DNA synthesis of normal and HPV-transformed keratinocytes in monolayer cultures and exerted a marked growth inhibitory effect in organotypic raft cultures. In control raft cultures, normal keratinocytes produced an epithelial sheet of approximately 10 cells in thickness that closely resembled normal cervical epithelium and was characterized by sparse Ki67 antigen-positive cells whereas HPV-transformed keratinocytes produced up to 15 poorly differentiated epithelial layers that were reminiscent of high grade cervical lesions seen in vivo and exhibited a full thickness Ki67 antigen expression. When normal and HPV-transformed keratinocytes were maintained in the presence of IFN-gamma, the epithelial sheet was reduced to a few cells in thickness and the density of Ki67 antigen-positive cells was decreased. A more pronounced growth inhibitory effect in monolayer and organotypic cultures was observed when IFN-gamma was associated with tumor necrosis factor-alpha Tumor necrosis factor-alpha alone reduced the DNA synthesis of normal keratinocytes but was significantly less effective than IFN-gamma to inhibit the growth of HPV-transformed keratinocytes. These results suggest that similar responses in vivo to regulatory molecules may play a role in the development of HPV-related lesions.

Analysis by in situ hybridization of cytokine mRNA expression in the murine developing thymus

We have used in situ hybridization to investigate the expression of IL-1, IL-2, IL-4, IL-6 and IFN-gamma genes by thymic cells during fetal development in mice. Two waves of mRNAs were detected in thymic cells for IL-1 at days 16 and 19 of gestation, for IL-2 at days 14 and 18, and for IL-4 at days 14 and 16. Three peaks for IL-6 were observed at days 13, 17 and around birth. Finally, only one peak of cells positive for IFN-gamma was detected. Whereas cells positive for IL-1 were generally grouped and more often localized in the external area of the thymus, the other positive cells were isolated and evenly distributed in the thymus. Our results illustrated the presence of cytokine transcripts in the developing thymus following a developmentally controlled sequence and support the hypothesis that cytokines could play a role in T cell development.

A RadLV-induced gamma delta T cell lymphoma displaying an antitumoral cytotoxicity

We described previously the induction by RadLV infection of a lymphoma (NS8) expressing a cytolytic activity against an MCA-induced fibrosarcoma. We report here that the cytolytic activity of these immortalized CD3+, CD8+ T cells is non-MHC-restricted. We then determined the structure and expression of the TCR chains expressed by these cells. Only partial rearrangement of the beta chain associated to an abnormally short transcript was detected in NS8 cells, whereas the gamma chain is rearranged and normally transcribed. On the opposite, rearrangement and expression of these genes were found in the other RadLV-induced lymphomas analysed. Moreover, gamma delta TCR proteins were detected on the cell surface of NS8 cells only, whereas the alpha beta complex, presents on the other T cell lines, was not expressed by NS8 cells. The ability of NS8 cells or of cells obtained from activated lymph nodes (harvested from mice grafted with the T2 sarcoma used to induce the NS8 line) to lyse the T2 sarcoma cell line was analysed. With both types of lymphocytes, the cytotoxicity was partially inhibited by a preincubation of the effector cells with anti-gamma delta antibodies. These results demonstrate that gamma delta lymphocytes can mediate anti-tumour cytotoxicity and NS8 lymphoma line may be representative of the TCR gamma delta CD8+ T cell subpopulation expressing non MHC-restricted cytotoxicity and displaying antitumoral activity.

Flow cytometry in prostate cancer: histological and clinical correlation

DNA histograms were obtained by flow cytometry for 39 human prostate carcinomas (27 total prostatectomy specimens, 5 biopsies and 7 transuretral resections). The study was performed on formalin-fixed and paraffin-embedded material. In this report, ploidy index did not seem to be a good marker of prognosis as no significant variation in ploidy was found neither among the different stages nor among the different Gleason categories. Proliferative index of the tumors seemed to be a more sensitive parameter; a significant relation was observed between proliferative index and stage of the tumor. The authors discuss these results under the light of previously reported observations.

Population dynamics of CD4+ T cells lacking Thy-1 in murine retrovirus-induced immunodeficiency syndrome (MAIDS)

Increased numbers of CD4+ Thy-1- cells have been described in the spleen (SP) of mice with retrovirus-induced immunodeficiency (MAIDS). Since this phenotypic abnormality might have considerable functional importance, the expansion of the CD4+ Thy-1- subset in MAIDS was characterized further. CD4+ Thy-1- and Thy-1+ T-cells from infected mice expressed similar densities of CD3 and TCR alpha/beta. In contrast, the Thy-1- subset was uniformly CD44hi, even early in the disease when part of Thy-1+ cells were still CD44lo. The emergence of CD4+ Thy-1- cells occurred first in SP and lymph nodes and was observed later in thymus. The important fraction of CD4+ cells lacking Thy-1 normally present in Peyer's patches was only weakly modified. Despite the major expansion of the CD4+ Thy-1- phenotype, the proliferating fraction was not higher in this subset than in CD4+ Thy-1+ cells from infected mice. Persistence after hydroxyurea administration was identical in both subsets, indicating similar mean cell lifespans. Taken together, these results show that the major expansion of CD4+ Thy-1- T-cells in MAIDS is not ascribable solely to increased proliferation within this subset. Phenotypic analysis suggests that CD4+ Thy-1- cells result from the differentiation of Thy-1+ cells induced by activation signals related to retroviral infection.

Detection of human papillomaviruses in paraffin-embedded biopsies of cervical intraepithelial lesions: analysis by immunohistochemistry, in situ hybridization, and the polymerase chain reaction

One hundred and forty biopsies with an initial diagnosis of cervical intraepithelial lesion (CIL) were tested for the presence of human papillomavirus (HPV) by immunohistochemistry and in situ hybridization using commercial biotinylated probes (Vira-Type in situ assay; Digene Diagnostics, Silver Spring, MD) or probes labeled with digoxigenin by the random primer technique. Immunohistochemistry was more inferior to the in situ hybridization method, with a detection rate of 14% (20/140) compared to 61% (86/140) for the in situ assay with the digoxigenin-labeled probes. Biotinylated probes proved to be slightly less sensitive than digoxigenin-labeled probes, with a detection rate of 53% (74/140). Although less sensitive in our series taken as a whole, immunohistochemistry was positive in a few cases of CILs negative by in situ hybridization, so that the association of these techniques gave the highest detection rate (66%; 92/140). The CILs that remained negative with these methods (34%; 48/140) were investigated by the polymerase chain reaction (PCR) using consensus primers to determine definitively the presence of HPV in these lesions and were reviewed histologically to assess the diagnosis of CILs. The PCR method increased the detection rate of HPV in our series to 76% (107/140). The diagnosis of CILs was confirmed for all the biopsy specimens positive by PCR (15/15; 100%) and for all the HPV negative tissues with histological features of a high-grade lesions (7/7; 100%).(ABSTRACT TRUNCATED AT 250 WORDS)

Phenotypical and functional analyses of mononuclear cells during rejection of a transplanted murine fibrosarcoma

Repeated injections of mitomycin C-treated T2 fibrosarcoma cells into tumor-sensitized mice cause regression of a secondary tumor graft and more than 90% of the mice are cured. In the data presented here, an enhancement of the cytolytic cell-mediated activities measured in vitro against the specific T2 targets is shown in lymph nodes draining the tumor and in the spleen during the process of tumor rejection. Histopathologic studies revealed a rapid and marked accumulation of mononuclear cells mostly at the periphery of the rejected tumor tissue. A significant increase of CD8-positive, asialo GM1-positive and acid phosphatase-positive cells was observed in the rejected tumors whereas CD4-positive cells were similarly detected in both progressing and rejected tumor tissue. As macrophages seemed to be the population presenting the most persistent variation after immunization, the production of TNF-alpha was studied within the tumor site and in the lymphoid tissues during the regression process. Firstly, the presence of TNF-alpha within the cytoplasm of most of the adherent cell fractions isolated from the spleen and the tumor of immune mice was demonstrated by immunocytochemistry. Next, TNF-alpha mRNA-containing cells were determined by in situ hybridization of frozen tumor sections and identified essentially as tumor infiltrating macrophages. Finally, the macrophage populations isolated from tumors and from the spleen of immune mice were able to produce in vitro large quantities of TNF-alpha without exogenous stimulation. These findings support the role of TNF-alpha in the effector mechanisms contributing to the tumor regression process.

Detection of cytomegalovirus, Pneumocystis carinii, and aspergillus species in bronchoalveolar lavage fluid. A comparison of techniques

Cytomegalovirus (CMV), Pneumocystis carinii, and Aspergillus species are common causes of fatal pulmonary infections in immunocompromised hosts. Therefore, rapid and reliable methods of establishing the diagnosis of these types of pneumonia are essential. Bronchoalveolar lavage (BAL) has proved to be a rapid and safe procedure for procuring large numbers of bronchial and alveolar cells from the lung. To assess various methods of detecting CMV, P. carinii, and aspergillosis in lavage specimens, 47 BAL samples from adults at high risk for these infections were evaluated. The visualization of these agents was performed by cytologic examination and in situ hybridization for CMV; cytologic examination, Gomori's methenamine silver (GMS) stain, and immunofluorescence for P. carinii; and cytologic examination, GMS stain, and immunocytologic studies for Aspergillus species. Cytomegalovirus was detected in 2 of 47 specimens (4%) by cytologic examination and 7 of 47 (15%) by in situ hybridization. Cells with nuclear and/or cytoplasmic inclusions invariably were labeled with the CMV DNA probe. The weak diagnostic value of the cytologic examination resulted from the absence of characteristic inclusions in many specimens with positive results by in situ hybridization. P. carinii was the most frequent pathogen isolated from BAL fluid (9 of 47 cases; 19%). It was found in 1 of 47 specimens (2%) by the cytologic examination of Papanicolaou-stained smears, 4 of 47 (8.5%) by the GMS stain, and 8 of 47 (17%) by immunofluorescence. Most P. carinii-positive cases (five of nine cases) were detected by immunofluorescence only. Aspergillus species was diagnosed in 2 of 47 specimens (4%) by cytologic examination and GMS staining. Immunocytologic studies had positive results in these specimens and detected one additional case of Aspergillus infection (3 of 47 cases; 6%). These data show that techniques using CMV DNA probes and anti-P. carinii or anti-Aspergillus antibodies are rapid and more sensitive than conventional diagnostic procedures.

[Central function of the thymus in the recognition of neuroendocrine functions by T lymphocytes during their development]

The dual physiological role of the thymus in T cell positive and negative selection appears prominent in the establishment of appropriate host immune defenses. However, the cellular and molecular mechanisms underlying those thymic functions begin only to be understood. On the basis of our previous investigations about the thymic expression of different neuroendocrine-related signals, we have advanced a model which transposes at the peptide level the intervention of this primary lymphoid organ in both T cell positive and negative selective processes. There is now ample evidence that the thymic subcapsular and medullary epithelium is the site for synthesis of neurohypophysial (NHP)-related peptides (reviewed in Geenen et al., 1992a). We have also demonstrated that the epithelial component of thymic "nurse" cells (TNC) synthesizes NHP-related peptides and expresses a neuroendocrine-like phenotype (Geenen et al., 1988a). This observation was a remarkable example of the intimate neuroendocrine-immune interactions that take place during T cell ontogeny. Further immunocytochemical analyses have confirmed that one dominant NHP-related epitope belongs to the oxytocin (OT) lineage of the NHP peptide superfamily (Robert et al., 1991, 1992). The intrathymic coexpression of this OT-like epitope with a neurophysin protein domain is a strong argument for a local synthetic process similar to the hypothalamo-NHP one. However, the absence of ir-OT in secretory granules of thymic epithelial cells (TEC), as well as of NHP-related peptides in the supernatant of TEC cultures questioned the application to the thymus of the classical neurosecretory model established for hypothalamic magnocellular neurons (Scharrer & Scharrer, 1944).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of bone marrow sections, smears and immunohistological staining for immunoglobulin light chains in the diagnosis of benign and malignant plasma cell proliferations

Bone marrow specimens from 118 patients with clinical suspicion of multiple myeloma were studied to assess the diagnostic reliability of histological and cytological criteria. Plasma cell clonality was assessed by demonstrating light chain restriction. In most cases of multiple myeloma, the classical cytological and histological criteria were found. In eight cases in which the marrow contained less than 10% of plasma cells, there was discordance between the light microscopic and immunohistochemical findings. In six cases without evidence of multiple myeloma and with polyclonal plasma cells in bone marrow, abnormal plasma cells resembling a malignant proliferation were found. These findings indicate that comparison of histological and cytological results with immunohistological studies for immunoglobulin light chains in bone marrow biopsy sections can be helpful in the evaluation of patients with a suspicion of multiple myeloma and when the marrow contains less than 10% of plasma cells.

Misdiagnosed malignancy in transplanted organs

The case reports of three patients who received cancer-bearing organs at this institution are presented. A fourth recipient, who was to be transplanted with a cancerous kidney, was spared this disastrous complication. The relevant data regarding the donors is also alluded to, with special reference to the type and site of the primary malignancy. Following these case reports, the implications of these issues, their possible prevention, and further management are discussed.

Detection of Epstein-Barr virus in a case of undifferentiated nasopharyngeal carcinoma by in situ hybridization with digoxigenin-labelled PCR-generated probes

A case of nasopharyngeal carcinoma is presented. Epstein-Barr viral genome was identified in the neoplastic cells by in situ hybridization with digoxigenin-labelled polymerase chain reaction-generated probes. We report the development of this technique in paraffin-embedded sections and propose that such identification may prove valuable for the diagnosis of this tumour in routine material.

Evidence that insulin-like growth factor 2 (IGF2) is the dominant thymic peptide of the insulin superfamily

The central T-cell tolerance of neuroendocrine functions has been proposed to be primarily induced by the thymic repertoire of neuroendocrine self antigens. The present study aimed at characterizing the human thymic insulin-related autoantigen able to represent the pancreatic B-cell function in face of the developing T-cells. Immunofluorescence studies were performed on human and rat thymic sections, as well as on the rat IT-45R1 thymic epithelial cell line using several antibodies to epitopes of the insulin peptide superfamily. These studies identify beyond any doubt that insulin-like growth factor 2 (IGF2) is the dominant thymic peptide of the insulin family. The sequence of an insulin-derived autoantigen is proposed. This autoantigen is a nonamer and has a hydrophobic residue leucine (L) at position 9. In the human species, this autoantigen would primarily be tolerogenic for the pancreatic B-cell endocrine function during fetal development.

Efficient immunoselection of cytolytic effectors with a magnetic cell sorter

This paper describes a rapid and efficient method for the sorting of in vitro activated cytolytic effectors cells. For cytotoxic assays, a large number of cells with conserved function must be rapidly obtained. Immunomagnetic sorting was chosen because it is faster than flow cytometry sorting. The MACS system requires the use of paramagnetic beads of small diameter (100-150 nm), reputed to interfere minimally with cell function. In order to generate the cytolytic effectors, peripheral blood lymphocytes were cultivated in the presence of interleukin-2 (50 U/ml) and anti-CD3 monoclonal antibody (BMA030, 100 ng/ml) for 4 days. Cell separation was based on the membrane expression of the CD3 complex. The purity obtained for positive (CD3+) cell sorting with the MACS was higher than 95%. The purity of negative (CD3-) cell fraction was more variable, but further purification by flow cytometry rapidly yielded purity higher than 95%. Cytotoxic assays were performed against four target cell lines (K562, Daudi, HL60 and U937) and proliferation assays showed that both negatively and positively selected populations had conserved their function acquired during culture in the presence of anti-CD3 mAb and IL2.

Misdiagnosed malignancy in transplanted organs

The case reports of three patients who received cancer-bearing organs at this institution are presented. A fourth recipient, who was to be transplanted with a cancerous kidney, was spared this disastrous complication. The relevant data regarding the donors is also alluded to, with special reference to the type and site of the primary malignancy. Following these case reports, the implications of these issues, their possible prevention, and further management are discussed.

Fundic argyrophil cell hyperplasia in atrophic gastritis: a search for a sensitive diagnostic method

Hypergastrinemia induces argyrophil cell hyperplasia in oxyntic mucosa (FACH) in patients with non-antral atrophic gastritis, with or without pernicious anemia. This proliferation favours the development of carcinoid tumours. In order to determine the most usual appropriate method to document FACH, we have studied 29 consecutive fundic biopsies from 26 patients with fundic chronic gastritis. The study encompassed gastrinemia levels, standard histology permitting the classification of chronic gastritis, demonstration of FACH by Grimelius stain, immunohistochemical studies using NSE, chromogranin A and by electron microscopy. The FACH was classified for each stain as slight, moderate or severe. The study displayed a relationship between the grade of gastritis and the density of argyrophil endocrine cells in oxyntic mucosa assessed by Grimelius stain (p < 0.0001) and chromogranin A (P < 0.01). There was also a relationship between the serum gastrin level and the density of argyrophil endocrine cells detected by these two stains (p < 0.001). A highly significant correlation was observed between Grimelius stain and chromogranin A (p < 0.0001). On the other hand, no significant correlation was noted with either NSE or electron microscopy. We conclude that Grimelius stain and immunohistochemical studies against chromogranin A were the best methods for the demonstration of FACH in atrophic gastritis. One of these two techniques is sufficient in current practice for defining the patients at risk for subsequent surveillance.