Association between pelvic inflammatory disease, infertility, ectopic pregnancy and the development of ovarian serous borderline tumor, mucinous borderline tumor and low-grade serous carcinoma

OBJECTIVE

Risk factors for ovarian borderline tumors and low-grade serous carcinoma (LGSC) are poorly understood. The aim of this study was to examine the association between infertility, pelvic inflammatory disease (PID), endometriosis, ectopic pregnancy, hysterectomy, tubal ligation and parity and the risk of serous borderline tumor (SBT), mucinous borderline tumor (MBT) and LGSC.

METHODS

This was a population-based cohort study using linked administrative and hospital data. Participants were 441,382 women born between 1945 and 1975 who had been admitted to hospital in Western Australia between 1 January 1980 and 30 June 2014. We used Cox regression to estimate hazard ratios (HRs).

RESULTS

We observed an increased rate of SBT associated with infertility, PID and ectopic pregnancy (HRs and 95% CIs were, respectively, 1.98 (1.20-3.26); 1.95 (1.22-3.10) and 2.44 (1.20-4.96)). We did not detect an association between any of the factors under study and the rate of MBT. A diagnosis of PID was associated with an increased rate of LGSC (HR 2.90, 95% CI 1.21-6.94).

CONCLUSIONS

The association with PID supports the hypothesis that inflammatory processes within the upper gynaecological tract and/or peritoneum may predispose to the development of SBT and LGSC.

Risk of persistent or recurrent cervical neoplasia in patients with 'pure' adenocarcinoma-in-situ (AIS) or mixed AIS and high-grade cervical squamous neoplasia (cervical intra-epithelial neoplasia grades 2 and 3 (CIN 2/3)): a population-based study

OBJECTIVE

To compare outcomes of patients with pure adenocarcinoma-in-situ (AIS) and mixed AIS/CIN 2/3 lesions including the incidence of AIS persistence, recurrence and progression to adenocarcinoma.

DESIGN

Retrospective cohort study.

SETTING

Statewide population in Western Australia.

POPULATION

Women diagnosed with AIS between 2001 and 2012.

METHODS

We conducted a retrospective, population-based cohort study.

MAIN OUTCOME MEASURES

De-identified linked data were utilised to ascertain the association between patient age at excisional treatment, margin status, lesion type, lesion size, and risk of persistent AIS (defined as the presence of AIS <12 months from treatment), recurrent AIS (≥12 months post-treatment), and adenocarcinoma.

RESULTS

636 patients were eligible for analysis. The mean age was 32.3 years and median follow-up interval was 2.5 years. Within the study cohort, 266 patients (41.8%) had pure AIS and 370 (58.2%) had mixed AIS/CIN 2/3. Overall, 47 patients (7.4%) had AIS persistence/recurrence and 12 (1.9%) had adenocarcinoma. Factors associated with persistence/recurrence were pure AIS (hazard ratio (HR) 2.3; 95%CI 1.28-3.94; P = 0.005), age >30 years (HR 2.1; 95%CI 1.16-3.81; P = 0.015), positive endocervical margins (HR 5.8; 95%CI 3.05-10.92; P = <0.001) and AIS lesions >8 mm (HR 2.5; 95%CI 1.00-6.20; P = 0.049). A histologically positive AIS ectocervical margin was not associated with persistence/recurrence.

CONCLUSION

In this study, pure AIS was associated with greater risk of persistence/recurrence than was mixed AIS/CIN 2/3. AIS lesions >8 mm and positive endocervical margins were significant predictors for persistent or recurrent disease.

TWEETABLE ABSTRACT

Pure cervical adenocarcinoma-in-situ (AIS) may have greater risk of recurrence than AIS co-existing with CIN 2/3.

Novel BRAF and KRAS Mutations in Papillary Thyroid Carcinoma Arising in Struma Ovarii

Papillary carcinomas of thyroid type rarely arise within struma ovarii. There are limited data on the immunohistochemical and molecular features of these tumors. Three cases of papillary carcinoma arising in struma ovarii (PCSO) were identified. The clinicopathological features were reviewed and immunohistochemical staining for HBME-1, cytokeratin (CK) 19, and CD56 was performed. Tumor DNA was sequenced for somatic mutations using a panel of 26 oncogenes, with a particular focus on BRAF and KRAS mutations. The patients were aged 22, 48, and 55 years. All cases were FIGO stage IA. Two tumors were of classical histological type, and one was a follicular variant papillary carcinoma. All tumors expressed HBME-1 and two were positive for CK19. CD56 was negative in all three cases. One tumor demonstrated a BRAF G469A mutation in exon 11, and in a second case, a KRAS Q61K double base mutation in exon 3 was detected. These mutations have not been described previously in PCSO. No mutations were detected in the benign follicular components of the tumors adjacent to the malignant papillary tissue. None of the patients had tumor recurrence on clinical follow-up (range 11 months to 8½ years). HBME-1, CK19, and CD56 are useful immunohistochemical markers of PCSO. Novel BRAF and KRAS mutations were identified in two of three tumors suggesting that mutations in PCSO may differ from those commonly identified in papillary carcinoma of the eutopic thyroid. The clinical significance of these mutations is uncertain but follow-up data in this small series support the generally good prognosis of PCSO.

J-LEAPS vaccines initiate murine Th1 responses by activating dendritic cells

The Ligand Epitope Antigen Presentation System (LEAPS) converts a peptide containing a T cell epitope as small as 8 amino acids into an immunogen and directs the nature of the subsequent response. Tandem synthesis of the J peptide (a peptide from the beta-2-microglobulin) with peptides of 15 or 30 amino acids from HSV-1 or HIV made them immunogenic and promoted Th1 immune responses. Immunization of A/J or C57BL/6 mice with J-LEAPS heteroconjugates containing an epitope from the HSV-1 glycoprotein D (JgD) or an epitope from the HIV gag protein (JH) emulsified with Seppic ISA51 induced increased levels of IL-12p70 by day 3 and increased levels of interferon gamma (IFN-gamma) on days 10 and 24. Interestingly, levels of IL-10, TNF-alpha, and IL-6 did not change. Neither the H nor the gD peptides alone elicited responses and only weak responses followed immunization with the J peptide. Bone marrow (BM) cells became CD86 and CD11c positive within 48 h of treatment with JgD or JH. JH or JgD treatment promoted IL-12p70 production and expression of CD8 denoting the maturation and activation of a subclass of myeloid DCs. Pure cultures of immature myeloid DCs also responded to JgD treatment, forming clusters, developing dendrites, and producing IL-12p70 within 24 h. The JH or JgD treated bone marrow cells (JgD-DC) were necessary and sufficient to activate splenic T cells to produce IFN-gamma and the JgD-DC provided an antigen specific booster response to T cells from JgD immunized mice. Adoptive transfer of JgD-DC was also sufficient to initiate protective antigen specific immunity from lethal challenge with HSV-1. The J-LEAPS vaccines appear to act as an adjuvant and immunogen on DC precursors in a unique manner to promote activation and maturation into IL-12p70 producing DCs which then can initiate sufficient Th1 immune responses to elicit protection without production of acute phase cytokines.

Primary neuroblastoma of the mandible

Primary neuroblastoma of the mandible is rare with only seven cases reported to date. The diagnosis is made after any possible primary tumour has been adequately investigated for and excluded. We report a one-year nine-month-old girl with a primary neuroblastoma of the mandible and discuss its possible aetiology.

Propagation of mouse and human T cells with defined antigen specificity and function

Difficulties maintaining fully functional CD4+ T cells in culture have historically limited the study of their role in tumour rejection as well as other clinical applications. As the therapeutic value of current antitumour CD8+ T cell adoptive therapy becomes better defined, a strong impetus exists to determine optimal conditions for culturing antitumour CD4+ T cells. Our goal is to promote broadly polyclonal, antigen-specific CD4+ T cell responses of either Th1 or Th2 character for use in antitumour therapy or allograft facilitation, respectively. Similar obstacles exist in murine and human cultures: (1) during even brief periods of culture CD4+ T cells develop high 'background' reactivity to class II-positive antigen-presenting cells; (2) maintenance of antigen specificity as evidenced by cytokine secretion and short-term proliferation assays is insufficient to ensure bulk numerical expansion; (3) Th1-type CD4+ T cells often lose their potential for antigen-specific secretion of interleukin 2 on re-stimulation (though remain inducible by 12-O-tetradecanoylphorbol 13-acetate/ionomycin); (4) during prolonged culture selection pressure favours CD4+ subpopulations that recognize artifactual antigens such as culture medium proteins; (5) even with optimal culture conditions, cultured CD4+ T cells may function differently in vivo to uncultured CD4+ T cells. We have devised various strategies to surmount these obstacles by use of selected cytokines, antigen-presenting cells and timely culture manoeuvres.

Lack of effective MUC1 tumor antigen-specific immunity in MUC1-transgenic mice results from a Th/T regulatory cell imbalance that can be corrected by adoptive transfer of wild-type Th cells

Glycoprotein tumor Ag MUC1 is overexpressed on the majority of epithelial adenocarcinomas. CTLs that recognize MUC1 and can kill tumor cells that express this molecule have been found in cancer patients, yet they are present in low frequency and unable to eradicate MUC1(+) tumors. Patients also make anti-MUC1 Abs but predominantly of the IgM isotype reflecting the lack of effective MUC1-specific Th responses. Mice transgenic for the human MUC1 gene (MUC1-Tg) are similarly hyporesponsive to MUC1. We used a vaccine consisting of dendritic cells loaded with a long synthetic MUC1 peptide to investigate the fate and function of MUC1-specific CD4(+) Th elicited in wild-type (WT) or MUC1-Tg mice or adoptively transferred from vaccinated WT mice. We show that hyporesponsiveness of MUC1-Tg mice to this vaccine is a result of insufficient expansion of Th cells, while at the same time their regulatory T cells are efficiently expanded to the same extent as in WT mice and exert a profound suppression on MUC1-specific B and T cell responses in vivo. Adoptive transfer of WT Th cells relieved this suppression and enhanced T and B cell responses to subsequent MUC1 immunization. Our data suggest that the balance between Th and regulatory T cells is a critical parameter that could be modulated to improve the response to cancer vaccines.

A20/TNFAIP3, a new estrogen-regulated gene that confers tamoxifen resistance in breast cancer cells

The zinc-finger protein A20/TNFAIP3, an inhibitor of nuclear factor-kappaB (NF-kappaB) activation, has been shown to protect MCF-7 breast carcinoma cells from TNFalpha-induced apoptosis. As estrogen receptor (ER) status is an important parameter in the development and progression of breast cancer, we analysed the effect of 17beta-estradiol (E2) treatment on the expression of A20. We found that A20 is a new E2-regulated gene, whose expression correlates with ER expression in both cell lines and tumor samples. With the aim of investigating the impact of A20 expression on MCF-7 cells in response to ER ligands, we established stably transfected-MCF-7 cells overexpressing A20 (MCF-7-A20). These cells exhibited a phenotype of resistance to the 4-hydroxy-tamoxifen cytostatic and pro-apoptotic actions and of hyper-response to E2. Dysregulations in bax, bcl2, bak, phospho-bad, cyclin D1, cyclin E2, cyclin D2 and cyclin A2 proteins expression were shown to be related to the resistant phenotype developed by the MCF-7-A20 cells. Interestingly, we found that A20 was also overexpressed in MVLN and VP tamoxifen-resistant cell lines. Furthermore, high A20 expression levels were observed in more aggressive breast tumors (ER-negative, progesterone receptor-negative and high histological grade). These overall findings strongly suggest that A20 is a key protein involved in tamoxifen resistance, and thus represents both a new breast cancer marker and a promising target for developing new strategies to prevent the emergence of acquired mechanisms of drug resistance in breast cancer.

Molecular changes associated with the agonist activity of hydroxy-tamoxifen and the hyper-response to estradiol in hydroxy-tamoxifen-resistant breast cancer cell lines

The aim of this study was to explore the pharmacological response to 4-hydroxy-tamoxifen (OH-Tam) and to estradiol (E2) in three cell lines: MVLN, a human breast carcinoma cell line derived from MCF-7, and two MVLN-derived OH-Tam-resistant (OTR) cell lines, called CL6.8 and CL6.32. The OH-Tam response in the OTR cells was associated with the development of both an agonist activity of the drug on cell proliferation and the resistance of the cells to OH-Tam-induced apoptosis. The OTR cells also developed an increased sensitivity to the E2 growth-stimulating activity. To delineate the genes that determine such responses, we combined a mini-array-based gene-selection approach and an extensive real-time quantitative PCR exploration in the MVLN and OTR cell lines exposed to three pharmacological conditions: a 4-day treatment with E2, OH-Tam or both E2 and OH-Tam. Compiled data revealed a hyper-response to E2 and a modification of the OH-Tam pharmacological response (loss of antagonist action and agonist activity) at the gene-expression level. The proteins encoded by the genes selected in this study have been reported to be involved in the regulation of cell proliferation, cell transformation, DNA repair and apoptosis, or belong to the ErbB/epidermal growth factor receptor-driven pathway. Our data also provide evidence of changes in transcriptional co-regulator expression, elevated mitogen-activated protein kinase activity and increase in the phosphorylation status of estrogen receptor alpha on serine residue 118 in the OTR cell lines, suggesting the possible involvement of such mechanisms in the agonist activity of OH-Tam and/or the hyper-response of cells to E2. Taken together, our study should enhance our knowledge of the multifactorial events associated with the development of Tam resistance in two independent cell lines issued from the same selection process and should help in the identification of potential molecular targets for diagnosis or therapy.

Traumatismes du rachis chez l’enfant

Spine injuries in the pediatric population can lead to instability and subsequent neurological damage. Initial work up includes frontal and lateral cross-table spine radiographs, completed by CT and MRI when any doubt exists about possible injury. At the cervical level, injuries frequently involve the first three segments.

Estrogen regulation in human breast cancer cells of new downstream gene targets involved in estrogen metabolism, cell proliferation and cell transformation

We explored, by cDNA mini-arrays, gene expression measurements of MVLN, a human breast carcinoma cell line derived from MCF-7, after 4 days of exposure to 17beta-estradiol (E(2)) treatment, in order to extend our understanding of the mechanism of the pharmacological action of estrogens. We focused on 22 genes involved in estrogen metabolism, cell proliferation regulation and cell transformation. The specificity of the E(2) response was reinforced by comparison with 4-hydroxytamoxifen (OH-Tam), ICI 182,780 and E(2)+OH-Tam expression profiles. Real-time quantitative PCR (RTQ-PCR) confirmed the variation of expression of known (TFF1, AREG, IRS1, IGFBP4, PCNA, ERBB2, CTSD, MYC) as well as novel (DLEU2, CCNA2, UGT1A1, ABCC3, ABCC5, TACC1, EFNA1, NOV, CSTA, MMP15, ZNF217) genes. The temporal response of these gene expression regulations was then investigated after 6 and 18 h of E(2) treatment and this allowed the identification of different time-course patterns. Cycloheximide treatment studies indicated first that estrogen affected the transcript levels of ABCC3 and ABCC5 through dissimilar pathways, and secondly that protein synthesis was needed for modulation of the expression of the CCNA2 and TACC1 genes by estrogens. Western blot analysis performed on TFF1, IRS1, IGFBP4, amphiregulin, PCNA, cyclin A2, TACC1 and ABCC5 proteins confirmed the mini-array and RTQ-PCR data, even for genes harboring low variations of mRNA expression. Our findings should enhance the understanding of changes induced by E(2) on the transcriptional program of human E(2)-responsive cells and permit the identification of new potential diagnostic/prognostic tools for the monitoring of estrogen-related disease conditions such as breast cancer.

Therapeutic vaccine generated by electrofusion of dendritic cells and tumour cells

Immunotherapy with fusion of dendritic cells (DCs) and tumour cells potentially confers the advantages of DC antigen-presenting functionality and a continuous source of unaltered tumour antigens. However, fusion using chemical or viral fusogens has been inefficient. We have recently developed a high throughput electrofusion technique with which very efficient fusion rates (15-54%) were observed in over 300 experiments, using a variety of murine and human tumour cell lines. The fused cells display a mature DC phenotype and express tumour-associated antigens. In two pre-clinical animal models (B16 melanoma transduced with the LacZ gene and the MCA 205 fibrosarcoma), a single vaccination of mice bearing tumours established in the lung, brain and skin resulted in tumour regression and prolongation of life. However, therapeutic efficacy required the administration of adjuvants such as IL-12 and OX-40R mAbs. Effective immunotherapy also required the delivery of fusion cells directly into lymphoid organs (spleen or lymph nodes). Using five defined human T cell lines derived from melanoma patients, allogeneic DCs of HLA-A2, HLA-DR4 and HLA-DR7 haplotypes fused with MART-1, gp100, tyrosinase and TRP-2 expressing 888 mel melanoma cells were analysed for their ability to stimulate specific cytokine (IFN-gamma and GM-CSF) secretion. DC-888 mel hybrids presented all tumour-associated epitopes to both CD4 and CD8 T cell lines in the context of MHC class II and I molecules, respectively. The therapeutic efficacy of a DC-tumour fusion vaccine is now being evaluated for the treatment of metastatic melanoma.

T-cell adoptive therapy of tumors: mechanisms of improved therapeutic performance

The T cells of many cancer patients are naturally sensitized to tumor-associated antigens (Ag), or they can readily be sensitized with vaccine maneuvers. In melanoma patients, the adoptive transfer of such T cells can often be causally linked to the objective regression of established tumors. So far, few patients have shown sustained clinical benefit from such therapy, but preclinical mouse studies have now clearly delineated the hurdles that must be overcome to render T-cell-based antitumor therapy effective. Contrary to earlier expectations, it is now established that remarkably potent CD4+ and CD8+ pre-effector T cells are naturally sensitized even in mice bearing progressive, weakly immunogenic tumors. However, such T cells often display signal transduction impairments as a consequence of the tumor environment, which limit their acquisition of optimal effector function. Extracorporealization and culture of these tumor-sensitized T cells with appropriate activation stimuli not only restores normal signal transduction, but also confers resolute effector activity that can often sustain tumor rejection upon reinfusion. In mouse studies, the L-selectin(low) fraction of T cells in tumor-draining lymph nodes (TDLN) constitutes the potent pre-effector population and comprises both CD4+ and helper-independent CD8+ T cells. Appropriate in vitro activation confers an apparently unrestricted trafficking capacity to this fraction, and even the ability to proliferate within the tumor bed, leading to unprecedented tumor rejection at anatomic sites (e.g., subcutaneous and intracranial) that were historically refractory to such treatment. Such results underscore the surprising capacity of appropriately activated effector T cells to withstand the immunosuppressive, tolerogenic, and apoptotic influences of the typical tumor environment. Given the increasingly appreciated and critical communications between T cells and host Ag-presenting cells (APC), which cross-present tumor Ag, it is likely that dendritic cell-based vaccine maneuvers that promote sensitization of T1-committed L-selectin(low) antitumor T cells will play an increasingly important role in adoptive therapy strategies.

CD14+ monocytes as dendritic cell precursors: diverse maturation-inducing pathways lead to common activation of NF-kappab/RelB

Dendritic cells are extremely potent antigen-presenting cells that are primarily responsible for the sensitization of naïve T cells to protein antigen in vivo. For this reason, dendritic cells are the focus of intense study. Despite this interest, relatively little information is available on the signal transduction pathways that regulate the development and activity of these cells. The last several years, however, have seen a steady accumulation of data regarding methods to cultivate large numbers of DC, the characterization of attendant signals that drive DC development from various precursor cells, and the induction of nuclear transcription factors that presumably direct alterations in gene expression that regulate aspects of DC development. In this review, we briefly summarize some of these findings, with emphasis on monocyte-derived dendritic cells and a discussion of two distinct types of signaling pathways that appear to regulate the final maturation of DC: one pathway calcium-dependent and cyclosporine A-sensitive, the other pathway CsA-insensitive. Although evidence suggests these signaling pathways are quite divergent in their upstream components, they both appear to activate NF-kappaB nuclear factors, particularly RelB.

Oral health care in the 21st century: implications for dental and medical education

The past decade has been turbulent for dental education, marked by debate about the future directions of the curriculum and the profession itself. The bulk of the dental school curriculum is still devoted to tooth restoration or replacement techniques, although the need for these procedures has declined. Some dental educators now advocate an oral physician model as the desired direction for the profession, with expanded training in systemic disease pathophysiology and a practice scope that extends beyond exclusive focus on the teeth and supporting structures. Proponents of this model contend for curriculum time with faculty who desire to maintain a technical focus. The outcome of this curricular tug-of-war has implications for medical education, because many oral health problems now fall into the overlapping educational and patient care environments of physicians, dentists, and other health care providers. Will physicians perceive the new dentist as an encroachment on territory or as a resource to enhance patient care? Within dentistry, the traditions of tooth restoration and prosthodontics shape the profession's culture. Are dental educators ready to reconfigure a curriculum that is deeply intertwined with the professional identity of 150,000 U.S. dentists practicing today? To stimulate thinking about these issues, the authors analyze the responses of dental education to changes in the public's oral health and to calls for curricular reform, propose strategies for modifying the way dentists are prepared for their professional responsibilities, and explore the sociology of change in academic institutions, because elements of dental education targeted for reform are revered components of school culture.

Augmentation versus inhibition: effects of conjunctional OX-40 receptor monoclonal antibody and IL-2 treatment on adoptive immunotherapy of advanced tumor

Therapeutic efficacy of adoptive immunotherapy of malignancies is proportional to the number of effector T cells transferred. Traditionally, exogenous IL-2 treatment has been used to promote the survival and function of transferred cells. Recently, we described the therapeutic effects of in vivo ligation of the costimulatory receptor, OX-40R, on activated T cells during early tumor growth. In this study, we examined the effects of IL-2 and OX-40R mAb on adoptive immunotherapy of advanced tumors. For treatment of 10-day 3-methylcholanthrene 205 pulmonary metastases, systemic transfer of 50 x 10(6) activated tumor-draining lymph node T cells resulted in >99% reduction of metastatic nodules. With either IL-2 or OX-40R mAb conjunctional treatment, only 20 x 10(6) cells were required. Advanced 10-day 3-methylcholanthrene 205 intracranial tumors could be cured by the transfer of 15 x 10(6) L-selectin(low) T cells derived from draining lymph nodes. In this situation, IL-2 administration inhibited therapeutic effects of the transferred cells. By contrast, 5 x 10(6) T cells were sufficient to cure all mice if OX-40R mAb was administrated. Studies on trafficking of systemically transferred T cells revealed that IL-2, but not OX-40R mAb, impeded tumor infiltration by T cells. Tumor regression required participation of both CD4 and CD8 T cells. Because only CD4 T cells expressed OX-40R at cell transfer, direct CD4 T cell activation is possible. Alternatively, OX-40R might be up-regulated on transferred T cells at the tumor site, rendering them reactive to the mAb. Our study suggests OX-40R mAb to be a reagent of choice to augment T cell adoptive immunotherapy in clinical trials.

Calcium signaling inhibits interleukin-12 production and activates CD83(+) dendritic cells that induce Th2 cell development

Mature dendritic cells (DCs), in addition to providing costimulation, can define the Th1, in contrast to the Th2, nature of a T-cell response through the production of cytokines and chemokines. Because calcium signaling alone causes rapid DC maturation of both normal and transformed myeloid cells, it was evaluated whether calcium-mobilized DCs polarize T cells toward a Th1 or a Th2 phenotype. After human monocytes were cultured for 24 hours in serum-free medium and granulocyte-macrophage colony-stimulating factor to produce immature DCs, additional overnight culture with either calcium ionophore (CI) or interferon gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and soluble CD40L resulted in phenotypically mature DCs that produced interleukin-8 (IL-8) and displayed marked expression of CD80, CD86, CD40, CD54, CD83, DC-LAMP, and RelB. DCs matured by IFN-gamma, TNF-alpha, and soluble CD40L were additionally distinguished by undetectable CD4 expression, marked secretion of IL-12, IL-6, and MIP-1beta, and preferential ability to promote Th1/Tc1 characteristics during T-cell sensitization. In contrast, DCs matured by CI treatment were distinguished by CD4 expression, modest or absent levels of IL-12, IL-6, and MIP-1beta, and preferential ability to promote Th2/Tc2 characteristics. Calcium signaling selectively antagonized IL-12 production by mature DCs activated with IFN-gamma, TNF-alpha, and soluble CD40L. Although the activation of DCs by calcium signals is largely mediated through calcineurin phosphatase, the inhibition of IL-12 production by calcium signaling was independent of this enzyme. Naturally occurring calcium fluxes in immature DCs, therefore, negatively regulate Dc1 differentiation while promoting Dc2 characteristics and Th2/Tc2 polarization. Calcium-mobilized DCs may have clinical usefulness in treating disease states with excessive Th1/Tc1 activity, such as graft-versus-host disease or autoimmunity.

Diverse functional activity of CD83+ monocyte-derived dendritic cells and the implications for cancer vaccines

Antigen-loaded dendritic cells (DCs) provide key regulatory signals to T cells during a developing antitumor response. In addition to providing costimulation, mature DC provides cytokine and chemokine signals that can define the T1 vs T2 nature of the antitumor T-cell response as well as whether T cells engage in direct interactions with tumor cells. In serum-free culture conditions that hasten the differentiation of monocytes into mature DCs, certain agents, such as CD40L, accelerate phenotypic maturation (e.g., CD83 and costimulatory molecule expression) without influencing the acquisition of Dc1/Dc2 characteristics. In contrast, exposure to serum-free medium and interferon-gamma (IFN-gamma) rapidly influences CD83+ DCs to secrete high levels of IL-12, IL-6, and MIP-1beta, and promotes Dcl differentiation. In contrast, CD83+ DCs matured in serum-free medium in the absence of IFN-gamma, or in the presence of calcium signaling agents, prostaglandin-E2, or IFN-alpha, produce no IL-12, scant IL-6, and prodigious IL-8, MDC, and TARC, and promote Dc2 differentiation. T cells sensitized via IL-12-secreting, peptide-pulsed DCs secrete cytokines when subsequently exposed to relevant peptide-pulsed antigen-presenting cells (APCs) or to HLA-compatible tumor cells endogenously expressing the peptide. In contrast, T cells sensitized via IL-12 nonsecreting DC were limited to antigenic reactivation through APC contact rather than tumor cell contact. Therefore, the development of antitumor responses can be dramatically influenced not only by costimulation, but also by the cytokine and chemokine production of DCs, which must be considered in the development of cancer vaccines.

T cell-mediated tumor rejection displays diverse dependence upon perforin and IFN-gamma mechanisms that cannot be predicted from in vitro T cell characteristics

Experimental pulmonary metastases have been successfully treated by adoptive transfer of tumor-sensitized T cells from perforin knockout (KO) or Fas/APO-1 ligand(KO) mice, suggesting a prominent role for secretion of cytokines such as IFN-gamma. In the present study we confirmed that rejection of established methylcholanthrene-205 (MCA-205) pulmonary metastases displayed a requirement for T cell IFN-gamma expression. However, this requirement could be obviated by transferring larger numbers of tumor-sensitized IFN-gamma (KO) T cells or by immunosensitizing sublethal irradiation (500 rad) of the host before adoptive therapy. Extrapulmonary tumors (MCA-205 s.c. and intracranial) that required adjunct sublethal irradiation for treatment efficacy also displayed no requirement for host or T cell expression of IFN-gamma. Nonetheless, rejection of MCA-205 s.c. tumors and i.p. EL-4 tumors, but not MCA-205 pulmonary or intracranial tumors, displayed a significant requirement for T cell perforin expression (i.e., CTL participation). The capacity of T cells to lyse tumor targets and secrete IFN-gamma in vitro before adoptive transfer was nonpredictive of the roles of these activities in subsequent tumor rejection. Adoptive therapy studies employing KO mice are therefore indispensable for revealing a diversity of tumor rejection mechanisms that may lack in vitro correlation due to delays in their induction. Seemingly contradictory KO data from different studies are reconciled by the capacity of anti-tumor T cells to rely on alternative mechanisms when treated in larger numbers, the variable participation of CTL at different anatomic locations of tumor, and the apparent capacity of sublethal irradiation to provide a therapeutic alternative to host or T cell IFN-gamma production.

Helper-independent, L-selectinlow CD8+ T cells with broad anti-tumor efficacy are naturally sensitized during tumor progression

We recently reported that the CD4(+) T cell subset with low L-selectin expression (CD62L(low)) in tumor-draining lymph nodes (TDLN) can be culture activated and adoptively transferred to eradicate established pulmonary and intracranial tumors in syngeneic mice, even without coadministration of IL-2. We have extended these studies to characterize the small subset of L-selectin(low) CD8(+) T cells naturally present in TDLN of mice bearing weakly immunogenic tumors. Isolated L-selectin(low) CD8(+) T cells displayed the functional phenotype of helper-independent T cells, and when adoptively transferred could consistently eradicate, like L-selectin(low) CD4(+) T cells, both established pulmonary and intracranial tumors without coadministration of exogenous IL-2. Whereas adoptively transferred L-selectin(low) CD4(+) T cells were more potent on a cell number basis for eradicating 3-day intracranial and s.c. tumors, L-selectin(low) CD8(+) T cells were more potent against advanced (10-day) pulmonary metastases. Although the presence of CD4(+) T cells enhanced generation of L-selectin(low) CD8(+) effector T cells, the latter could also be obtained from CD4 knockout mice or normal mice in vivo depleted of CD4(+) T cells before tumor sensitization. Culture-activated L-selectin(low) CD8(+) T cells did not lyse relevant tumor targets in vitro, but secreted IFN-gamma and GM-CSF when specifically stimulated with relevant tumor preparations. These data indicate that even without specific vaccine maneuvers, progressive tumor growth leads to independent sensitization of both CD4(+) and CD8(+) anti-tumor T cells in TDLN, phenotypically L-selectin(low) at the time of harvest, each of which requires only culture activation to unmask highly potent stand-alone effector function.

Bacterial lipopolysaccharide, TNF-alpha, and calcium ionophore under serum-free conditions promote rapid dendritic cell-like differentiation in CD14+ monocytes through distinct pathways that activate NK-kappa B

To facilitate the study of signaling pathways involved in myeloid dendritic cell (DC) differentiation, we have developed a serum-free culture system in which human CD14+ peripheral blood monocytes differentiate rapidly in response to bacterial LPS, TNF-alpha, or calcium ionophore (CI). Within 48-96 h, depending on the inducing agent, the cells acquire many immunophenotypical, morphological, functional, and molecular properties of DC. However, there are significant differences in the signaling pathways used by these agents, because 1) LPS-induced, but not CI-induced, DC differentiation required TNF-alpha production; and 2) cyclosporin A inhibited differentiation induced by CI, but not that induced by LPS. Nevertheless, all three inducing agents activated members of the NF-kappaB family of transcription factors, including RelB, suggesting that despite differences in upstream elements, the signaling pathways all involve NF-kappaB. In this report we also demonstrate and offer an explanation for two observed forms of the RelB protein and show that RelB can be induced in myeloid cells, either directly or indirectly, through a calcium-dependent and cyclosporin A-sensitive pathway.

Cross-presentation of tumor antigens to effector T cells is sufficient to mediate effective immunotherapy of established intracranial tumors

The systemic adoptive transfer of tumor-sensitized T cells, activated ex vivo, can eliminate established intracranial tumors. Regression of MHC class II negative MCA 205 fibrosarcomas occurs optimally following adoptive transfer of both CD4 and CD8 tumor-sensitized T cells, indicating an important function for tumor-infiltrating APC. Here, we demonstrate that during an effector response, indirect presentation of tumor Ags to transferred T cells is sufficient to mediate intracranial tumor regression. BALB/c --> CB6F1 (H-2bxd) bone marrow chimeras were challenged with the MCA 205 fibrosarcoma (H-2b). The tumor grew progressively in the H-2b-tolerant chimeras and stimulated an immune response in tumor-draining lymph nodes. Tumor-sensitized lymph node T cells were activated ex vivo with anti-CD3 and IL-2, then adoptively transferred to sublethally irradiated BALB/c or C57BL/6 recipients bearing established intracranial MCA 205 tumors. The transferred T cells eradicated MCA 205 tumors in BALB/c recipients and demonstrated tumor specificity, but had no therapeutic efficacy in the C57BL/6 recipients. These data establish that tumor-associated host cell constituents provide sufficient Ag presentation to drive effector T cell function in the complete absence of direct tumor recognition. This effector mechanism has an evident capacity to remain operative in circumstances of immune escape, where the tumor does not express the relevant MHC molecules, and may have importance even at times when direct CTL recognition also remains operative.

Calcium ionophore activation of chronic myelogenous leukemia progenitor cells into dendritic cells is mediated by calcineurin phosphatase

We have previously demonstrated that Ph+ myeloid progenitor cells of patients with chronic myeloid leukemia (CML) can acquire characteristics of mature dendritic cells (DC) following calcium mobilization with calcium ionophore (A23187, CI). In this study we characterize the intracellular signaling pathway by which CI induces the acquisition of DC features in these leukemic cells. CI-induced activation of CML cells is attenuated by the calcineurin phosphatase inhibitor cyclosporin A (CsA) as well as the calmodulin (CaM) antagonist W-7. These cause ablation of both the CI-induced immunophenotypic expression of DC markers and immunostimulatory properties in mixed leukocyte responses (MLR). Minimal blocking effect was observed when Ca(2+)/CaM kinase II (281-301) inhibitor was added to the cultures. These findings suggest a Ca(2+)-dependent mechanism for the CI-induced activation of CML cells into antigen-presenting cells (APC), which is primarily mediated through the CaM/calcineurin pathway.

CD4+ T cells in adoptive immunotherapy and the indirect mechanism of tumor rejection

Tumor-specific CD4+ effector T cells often play a decisive role in immunologic tumor rejection, in some cases without evident co-participation of CD8+ T cells. During such CD4+ T-cell-mediated rejection there is often no detectable direct contact between T cells and tumor cells. Optimally prepared, adoptively transferred CD4+ T cells can reject established tumors with great efficiency even when targeted tumor cells express no MHC Class II molecules, implying that recognition of tumor antigen (Ag) occurs via MHC Class II-expressing host antigen-presenting cells (APC) within the tumor. Because consequent rejection also excludes Ag-specific contact between CD4+ T cells and MHC Class IIneg tumor cells, the most critical CD4+ T-cell-mediated event is likely cytokine release, resulting in an accumulation and activation of accessory cells such as tumoricidal macrophages and lymphokine-activated killer cells. Although such an indirect rejection mechanism may appear antithetical to popular strategies centered on CD8+ cytotoxic T cell (CTL), current evidence suggest that even CD8+ T-cell-mediated recognition/rejection often bypasses direct tumor cell contact and is largely cytokine mediated. While CTL are likely to participate prominently in many models of tumor rejection, indirect mechanisms of recognition/rejection have the theoretical advantage of remaining operative even when individual tumor cells evade direct contact by down-regulating MHC and/or Ag expression.

T cell adoptive immunotherapy of newly diagnosed gliomas

Patients with newly diagnosed gliomas were treated with adoptive transfer of ex vivo activated T lymphocytes, derived from lymph nodes (LNs) draining autologous tumor vaccines, to determine the long-term toxicity of this treatment. Twelve consecutive patients were enrolled: 2 with grade II astrocytoma, 4 with anaplastic gliomas, and 6 with glioblastoma multiforme. Patients were injected intradermally with short-term cultured autologous irradiated tumor cells, admixed with granulocyte macrophage colony-stimulating factor, to stimulate draining LNs. The LN cells were activated with staphylococcal enterotoxin A for 48 h and then cultured in medium containing interleukin 2 for an additional 6-8 days and subsequently transferred i.v. to the patients. The number of cells obtained from the LNs ranged from 9 x 10(7) to 1.1 x 10(9), and the median cell proliferation was 41-fold. The dose of T cells infused ranged from 0.6 to 5.5 x 10(10) with a median of 1.1 x 10(10), the majority of which were CD 4+ (mean, 71%). The entire treatment was performed as outpatient therapy and was associated with a toxicity of grade 2 or less, consisting mainly of fever, nausea, and myalgias during the first 24 h. There were no indications of late adverse events from this treatment even among three patients with follow-up greater than 2 years post T cell transfer. Moreover, four patients demonstrated partial regression of residual tumor. This Phase I clinical trial of adoptive immunotherapy for patients with newly diagnosed malignant gliomas demonstrates feasibility, lack of long-term toxicity, and several objective clinical responses.

Granulocyte-macrophage colony-stimulating factor, interleukin-2, and interleukin-12 synergize with calcium ionophore to enhance dendritic cell function

The authors previously showed that monocytes treated with calcium ionophore (CI) acquire characteristics of mature dendritic cells (DC) in part through a calcineurin-dependent pathway. In this study, the authors evaluated the ability of granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin-2 (IL-2), and interleukin-12 (IL-12) alone or in combination with CI to induce DC characteristics in peripheral blood monocytes. Monocytes obtained by leukapheresis and countercurrent centrifugal elutriation were cultured with calcium, cytokines, or both, profiled by flow cytometry, and assessed for antigen uptake and sensitization of autologous CD8+ T cells to antigen. Monocytes treated with the combination of GM-CSF, IL-2, and IL-12 resulted in immunophenotypic and antigen uptake profiles typical of immature DC, including loss of surface CD14 expression, de novo low-level expression of B7.1, negligible CD83 expression, marked enhancement of CD40 and ICAM-1, and high major histocompatibility complex class I and II levels. A high level of antigen uptake by macro-pinocytosis was observed. In contrast, CI treatment significantly up-regulates B7.1, B7.2, CD40, CD54, and CD83 and substantially down-regulates CD14 and macro-pinocytosis, a profile consistent with mature DC. Many CI-induced modulations, but none resulting from cytokine treatment alone, were inhibited by the calcineurin phosphatase inhibitor cyclosporin A. Compared with monocytes treated with CI alone, combined treatment of monocytes with GM-CSF, IL-2, IL-12, and CI augmented B7.1 and CD83 expression and enhanced sensitization of autologous CD8+ T cells to melanoma-antigen-derived peptides. These results suggest that several independent pathways of DC activation can cooperatively enhance the function of monocyte-derived DC.

Macrophage scavenger receptor CD36 is the major receptor for LDL modified by monocyte-generated reactive nitrogen species

The oxidative conversion of LDL into an atherogenic form is considered a pivotal event in the development of cardiovascular disease. Recent studies have identified reactive nitrogen species generated by monocytes by way of the myeloperoxidase-hydrogen peroxide-nitrite (MPO-H(2)O(2)-NO(2)(-)) system as a novel mechanism for converting LDL into a high-uptake form (NO(2)-LDL) for macrophages. We now identify the scavenger receptor CD36 as the major receptor responsible for high-affinity and saturable cellular recognition of NO(2)-LDL by murine and human macrophages. Using cells stably transfected with CD36, CD36-specific blocking mAbs, and CD36-null macrophages, we demonstrated CD36-dependent binding, cholesterol loading, and macrophage foam cell formation after exposure to NO(2)-LDL. Modification of LDL by the MPO-H(2)O(2)-NO(2)(-) system in the presence of up to 80% lipoprotein-deficient serum (LPDS) still resulted in the conversion of the lipoprotein into a high-uptake form for macrophages, whereas addition of less than 5% LPDS totally blocked Cu(2+)-catalyzed LDL oxidation and conversion into a ligand for CD36. Competition studies demonstrated that lipid oxidation products derived from 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphocholine can serve as essential moieties on NO(2)-LDL recognized by CD36. Collectively, these results suggest that MPO-dependent conversion of LDL into a ligand for CD36 is a likely pathway for generating foam cells in vivo. MPO secreted from activated phagocytes may also tag phospholipid-containing targets for removal by CD36-positive cells.

Overview of the radiology of juvenile idiopathic arthritis (JIA)

Plain films remain the basic tool for diagnosis and follow-up evaluation of juvenile idiopathic arthritis (JIA). In this paper, we review the new classification of JIA: systemic arthritis. oligoarthritis (persistent), oligoarthritis (extended), polyarticular arthritis (rheumatoid factor negative), polyarticular arthritis (rheumatoid factor positive), enthesitis-related arthritis, psoriatic arthritis and unclassified arthritis. We will also review regional abnormalities of three stages: an early stage, an intermediate stage, a late stage, as well as the differential diagnosis.

Rheumatological presentation of developmental bone diseases

Developmental bone disease may be present, with rheumatological disorders as the major symptoms, even in children. The major lesions encountered are early osteo arthritis, osteo chondromatosis and vertebral involvement with two leading types, pseudo Scheuermann's disease or pseudo ankylosing spondylitis. This paper presents the different features and lists the rheumatological problems in bone dysplasia.

Biochemical characterization of different conformational states of the Sf9 cell-purified p53His175 mutant protein

In this study, we expressed and purified the p53 mutant encoded by the His175 allele (p53His175) in a baculovirus expression system in order to study the folding and the DNA binding activity of the protein. A two-site ELISA revealed that purified p53His175 protein preferentially displayed a PAb1620 conformation, which appeared to be not sufficient to interact specifically with DNA. The cryptic DNA binding activity of this mutant was then investigated by electrophoretic mobility shift assay in the presence of anti-p53 antibodies, and shown to be refractory to significant activation by PAb421 (a potent allosteric activator of wild-type p53's DNA binding activity). Nevertheless, p53His175 DNA binding was regulated by antibodies targeting the N-terminal region of the protein. Furthermore, while the protein preferentially displayed a PAb1620 conformation, our data suggested the existence of an equilibrium between at least two folding states of the protein (PAb1620 and PAb240 conformations). A model rationalizing the conformation, antibody-interacting ability and DNA binding regulation potential of p53His175 is presented.

Formation of nitric oxide-derived oxidants by myeloperoxidase in monocytes: pathways for monocyte-mediated protein nitration and lipid peroxidation In vivo

Protein nitration and lipid peroxidation are implicated in the pathogenesis of atherosclerosis; however, neither the cellular mediators nor the reaction pathways for these events in vivo are established. In the present study, we examined the chemical pathways available to monocytes for generating reactive nitrogen species and explored their potential contribution to the protein nitration and lipid peroxidation of biological targets. Isolated human monocytes activated in media containing physiologically relevant levels of nitrite (NO(2)(-)), a major end product of nitric oxide ((*)NO) metabolism, nitrate apolipoprotein B-100 tyrosine residues and initiate LDL lipid peroxidation. LDL nitration (assessed by gas chromatography-mass spectrometry quantification of nitrotyrosine) and lipid peroxidation (assessed by high-performance liquid chromatography with online tandem mass spectrometric quantification of distinct products) required cell activation and NO(2)(-); occurred in the presence of metal chelators, superoxide dismutase (SOD), and scavengers of hypohalous acids; and was blocked by myeloperoxidase (MPO) inhibitors and catalase. Monocytes activated in the presence of the exogenous (*)NO generator PAPA NONOate (Z-[N-(3-aminopropyl)-N-(n-propyl)amino]diazen-1-ium-1,2- diolate) promoted LDL protein nitration and lipid peroxidation by a combination of pathways. At low rates of (*)NO flux, both protein nitration and lipid peroxidation were inhibited by catalase and peroxidase inhibitors but not SOD, suggesting a role for MPO. As rates of (*)NO flux increased, both nitrotyrosine formation and 9-hydroxy-10,12-octadecadienoate/9-hydroperoxy-10,12-octadecadieno ic acid production by monocytes became insensitive to the presence of catalase or peroxidase inhibitors, but they were increasingly inhibited by SOD and methionine, suggesting a role for peroxynitrite. Collectively, these results demonstrate that monocytes use distinct mechanisms for generating (*)NO-derived oxidants, and they identify MPO as a source of nitrating intermediates in monocytes.

Calcium signaling induces acquisition of dendritic cell characteristics in chronic myelogenous leukemia myeloid progenitor cells

Effective host T lymphocyte sensitization to malignant cells depends on successful antigen presentation. In this study, we examined the capacity of malignant myeloid progenitor cells of patients in the chronic phase of chronic myelogenous leukemia (CML) to acquire characteristics of activated dendritic cells (DCs) after intracellular calcium mobilization, thereby bypassing a need for third-party antigen-presenting cells. Treatment of purified CD33(+) CML cells from 15 patients with calcium ionophore (CI) consistently resulted in de novo expression of the costimulatory molecules CD80 (B7.1) and CD86 (B7.2), CD40 and the DC-specific activation marker CD83, as well as marked up-regulation of MHC class I and II molecules and the adhesion molecule CD54. Most of these changes occurred within 24 hr of treatment. Morphologically, CI-treated CML cells developed long dendritic projections similar to those seen in mature DCs. Functionally, CI-treated CML cells provided stimulation of allogeneic T lymphocytes 10- to 20-fold that of untreated CML cells or untreated monocytes. Fluorescent in situ hybridization of CI-activated CML cells confirmed their leukemic origin by displaying the typical bcr/abl fusion signal. No difference in bcr/abl translocation percentages between untreated and CI-treated CML nuclei was observed. These observations indicate that calcium mobilization may constitute a valuable approach for rapidly and reliably generating CML-derived DCs for immunotherapy of CML.

Calcium ionophore-treated myeloid cells acquire many dendritic cell characteristics independent of prior differentiation state, transformation status, or sensitivity to biologic agents

We previously reported that treatment of human peripheral blood monocytes or dendritic cells (DC) with calcium ionophore (CI) led to the rapid (18 hour) acquisition of many characteristics of mature DC, including CD83 expression. We therefore investigated whether less-mature myeloid cells were similarly susceptible to rapid CI activation. Although the promyelocytic leukemia line HL-60 was refractory to cytokine differentiation, CI treatment induced near-uniform overnight expression of CD83, CD80 (B7.1), and CD86 (B7. 2), as well as additional characteristics of mature DC. Several cytokines that alone had restricted impact on HL-60 could enhance CI-induced differentiation and resultant T-cell sensitizing capacity. In parallel studies, CD34(pos) cells cultured from normal donor bone marrow developed marked DC-like morphology after overnight treatment with either rhCD40L or CI, but only CI simultaneously induced upregulation of CD83, CD80, and CD86. This contrasted to peripheral blood monocytes, in which such upregulation could be induced with either CI or rhCD40L treatment. We conclude that normal and transformed myeloid cells at many stages of ontogeny possess the capacity to rapidly acquire many properties of mature DC in response to CI treatment. This apparent ability to respond to calcium mobilization, even when putative signal-transducing agents are inoperative, suggests strategies for implementing host antileukemic immune responses.

Calcium mobilization in human myeloid cells results in acquisition of individual dendritic cell-like characteristics through discrete signaling pathways

We have shown previously that calcium ionophore (CI) treatment of various myeloid origin cells results in rapid acquisition of properties associated with mature, activated dendritic cells. These properties include increased CD83 and costimulatory molecule expression, tendencies to form dendritic processes, loss of CD14 expression by monocytes, and typically an enhanced capacity to sensitize T lymphocytes to Ag. We here analyze the intracellular signaling pathways by which CI induces acquisition of such properties. Thapsigargin, which raises intracellular Ca2+ levels by antagonizing its sequestration, induced immunophenotypic and morphologic changes that paralleled CI treatment. CI-induced activation was broadly attenuated by the Ca2+ chelating compound EGTA and by calmodulin antagonists trifluoperazine dimaleate and W-7. However, antagonists of signaling pathways downstream to calmodulin displayed more selective inhibitory effects. Calcineurin antagonists cyclosporin A and the FK-506 analogue, ascomycin, diminished costimulatory molecule and CD83 expression, as well as formation of dendritic processes in CI-treated myeloid cells, and strongly attenuated the T cell allosensitizing capacity of CI-treated HL-60 cells. These calcineurin antagonists displayed minimal effect on CI-induced CD14 down-regulation in monocytes. In contrast, the calmodulin-dependent protein kinase antagonists, K252a and KT5926, while displaying only modest effects on CI-induced costimulatory molecule and CD83 expression, strongly blocked CD14 down-regulation. These results are consistent with a Ca2+-dependent mechanism for CI-induced differentiation of myeloid cells, and indicate that multiple discrete signaling pathways downstream to calcium mobilization and calmodulin activation may be essential in regulating this process.

Ischio-vertebral dysplasia: a distinct entity

BACKGROUND

Kyphoscoliosis is a complication of some bone dysplasias, including cleidocranial dysplasia.

OBJECTIVES

We report a distinct disorder with defective ossification of the ischial rami, severe kyphoscoliosis and normal clavicles. Early recognition of this syndrome allows prevention of complications.

MATERIALS AND METHODS

All patient cases (aged 1 day to 33 years) were selected according to the above criteria, with special attention to radiological findings, family history and follow-up (5-30 years).

RESULTS

In all eight patients, we observed the following: (a) Severe thoracic scoliosis of early onset and rapid progression, leading to rotatory dislocation. Spinal cord compression occurred in four cases with respiratory problems related to chest deformity. (b) Bilateral and symmetrical incomplete ossification of the ischial rami. (c) Peculiar facies with retrognathia. (d) Normal clavicles. Three patients were from the same family (grandmother, mother and daughter).

CONCLUSION

Ischio-vertebral dysplasia seems to represent a true entity, with radiological and genetic findings that make it distinct from cleidocranial dysostosis. The association of kyphoscoliosis and these pelvic abnormalities is specific for this condition. Neurological and respiratory complications can be avoided if the condition is recognised early and early treatment is instituted.

Characterization of a new intrabody directed against the N-terminal region of human p53

Genes encoding the rearranged immunoglobulin heavy and light chain variable regions of DO-1, a monoclonal antibody directed against human p53, have been used to construct a single-chain antibody. DO-1 recognizes an N-terminal epitope in the region involved in the transactivation function of p53 and the binding of Mdm2. The DO-1 single chain scFv expressed in the periplasm of E. coli or at the surface of the filamentous phage M13 retained the immunological specificity and affinity of the full length antibody. Furthermore, the DO-1 recombinant antibody was able to inhibit the in vitro binding of Hdm2, and was shown to be a powerful protecting agent of p53's DNA binding activity at 37 degrees C. The DO-1 single-chain antibody has been used to construct single-chain intracellular antibodies (intrabodies) for expression in the cytoplasm and the nucleus of mammalian cells. These anti-p53 intrabodies were additionally modified by addition of a Ckappa domain to increase cytoplasmic and nuclear stability. Here we show that expression of the DO-1 single-chain antibody in the H1299 cell line results in an inhibition of p53's transactivation function. The DO-1 intrabody is a useful tool to study those functions of p53 driven by the N-terminal region of the protein.

Focal cortical dysplasia and hemimegalencephaly: histological and neuroimaging correlations

BACKGROUND

The classification of cerebral cortical dysplasia is difficult and there are histological similarities between focal cortical dysplasia (FCD) and hemimegalencephaly. Objectives. To correlate the MR features and histological data of cortical dysplasias.

MATERIALS AND METHODS

The MR appearances of 17 brains were examined. According to the signal intensity within the pathological area on T2-weighted (T2-W) sequences we selected two groups.

RESULTS

Group 1 comprised ten patients with high signal in the dysplastic area on T2-W images. This group included five hemimegalencephalies, three frontal quadramegalencephalies, and one gyral dysplasia. The pathological hemisphere was reduced in size in one case. The cortex was thickened in all cases on T1-weighted (T1-W) images. There was loss of delineation between white matter (WM) and grey matter (GM) in all cases on both T1-W and T2-W sequences. The differential diagnosis with tumour, neoplastic-like malformation or polymicrogyria was questionable. Group 2 comprised seven patients presenting without increased signal within the dysplastic area on T2-W images. WM and GM were of similar signal intensity in six cases, and delineation between white and grey matter was absent in all cases. There were mild abnormalities on T1-W sequences in all cases. The dysplasias were limited to a lobe in five cases and a gyrus in two cases. In all cases, depiction of the malformation was a greater diagnostic problem than the differential diagnosis.

CONCLUSIONS

A constant MR sign in our series was the loss of delineation between WM and GM in the dysplastic area. This correlated well with the observed histological disorganisation. Markedly high signal within the dysplastic area seems to be related to myelin abnormalities rather than glial cell abnormalities.

Calcium ionophore-treated peripheral blood monocytes and dendritic cells rapidly display characteristics of activated dendritic cells

Human peripheral blood contains a small subpopulation of immature dendritic cells (iDC) distinguished from circulating monocytes by their low expression of CD14. We utilized leukapheresis and countercurrent centrifugal elutriation to obtain myeloid origin mononuclear cell (MOMC) fractions of monocytes and iDC for study. These subpopulations were ultrastructurally and immunophenotypically similar before culture. After a 20- to 96-h culture either alone, with recombinant human granulocyte-monocyte CSF, or with endotoxin, greater up-regulation of costimulatory molecule expression was observed among iDC than among monocytes, and only iDC expressed the activation molecule CD83. Treatment with rhIL-4 caused many MOMC to develop morphologic properties of dendritic cells within 96 h, but costimulatory molecule up-regulation and CD14 down-regulation were heterogeneous, and CD83 expression was infrequent. In contrast, calcium ionophore (CI) treatment induced rapid and consistent effects in MOMC from both healthy volunteers and cancer patients, including down-regulated CD14 expression, acquisition of dendritic cell morphologic properties, up-regulated MHC and costimulatory molecule expression, and de novo CD83 expression. Many such effects occurred within 20 h of treatment. CI treatment activated purified CD14+ monocytes and also enhanced the spontaneous activation of purified CD14-/dim iDC in culture. Unfractionated MOMC, purified monocytes, and purified iDC displayed equivalently enhanced T cell-sensitizing efficiency following CI treatment. CD4+ T cell sensitization to keyhole limpet hemocyanin and CD8+ T cell sensitization to MART-1 melanoma-associated peptide were achieved in a single culture stimulation. Therefore, circulating monocytes and iDC can be induced by CI to manifest properties of activated DC, providing large numbers of efficient, nontransformed autologous APC for T cell sensitization strategies.

Calcium ionophore-treated peripheral blood monocytes and dendritic cells rapidly display characteristics of activated dendritic cells

Human peripheral blood contains a small subpopulation of immature dendritic cells (iDC) distinguished from circulating monocytes by their low expression of CD14. We utilized leukapheresis and countercurrent centrifugal elutriation to obtain myeloid origin mononuclear cell (MOMC) fractions of monocytes and iDC for study. These subpopulations were ultrastructurally and immunophenotypically similar before culture. After a 20- to 96-h culture either alone, with recombinant human granulocyte-monocyte CSF, or with endotoxin, greater up-regulation of costimulatory molecule expression was observed among iDC than among monocytes, and only iDC expressed the activation molecule CD83. Treatment with rhIL-4 caused many MOMC to develop morphologic properties of dendritic cells within 96 h, but costimulatory molecule up-regulation and CD14 down-regulation were heterogeneous, and CD83 expression was infrequent. In contrast, calcium ionophore (CI) treatment induced rapid and consistent effects in MOMC from both healthy volunteers and cancer patients, including down-regulated CD14 expression, acquisition of dendritic cell morphologic properties, up-regulated MHC and costimulatory molecule expression, and de novo CD83 expression. Many such effects occurred within 20 h of treatment. CI treatment activated purified CD14+ monocytes and also enhanced the spontaneous activation of purified CD14-/dim iDC in culture. Unfractionated MOMC, purified monocytes, and purified iDC displayed equivalently enhanced T cell-sensitizing efficiency following CI treatment. CD4+ T cell sensitization to keyhole limpet hemocyanin and CD8+ T cell sensitization to MART-1 melanoma-associated peptide were achieved in a single culture stimulation. Therefore, circulating monocytes and iDC can be induced by CI to manifest properties of activated DC, providing large numbers of efficient, nontransformed autologous APC for T cell sensitization strategies.

Necrotizing enterocolitis: diagnosis with CT examination of urine after enteral administration of iodinated water-soluble contrast material

PURPOSE

To develop a new method for diagnosing necrotizing enterocolitis with use of computed tomography (CT).

MATERIALS AND METHODS

Urine specimens from 22 neonates were obtained 8-12 hours after iohexol was administered enterally. Twelve neonates had suspected (n = 5) or definite (n = 7) necrotizing enterocolitis, and 10 neonates without necrotizing enterocolitis underwent routine upper gastrointestinal study. Urine from another 13 neonates without necrotizing enterocolitis who did not receive iohexol was collected. The attenuation coefficient of each urine specimen was determined with CT.

RESULTS

The mean CT attenuation coefficient of urine from neonates who did not receive iohexol was 5.6 HU +/- 3.9, and that from neonates without necrotizing enterocolitis who underwent upper gastrointestinal study was 6.7 HU +/- 3.2. The mean CT attenuation coefficient of urine from patients with suspected necrotizing enterocolitis was 26.0 HU +/- 3.4, and that in patients with definite necrotizing enterocolitis was 71.0 HU +/- 18.8. The mean CT attenuation coefficients in neonates with necrotizing enterocolitis were significantly different from that in patients without necrotizing enterocolitis who underwent upper gastrointestinal study.

CONCLUSION

Urine from neonates with necrotizing enterocolitis show significantly higher CT attenuation coefficients than those from patients without necrotizing enterocolitis. CT examination of urine may allow early detection of necrotizing enterocolitis.

Immunohistochemical determination of hepatic cytochrome P-4502E1 in formalin-fixed, paraffin-embedded sections

Cytochrome P-4502E1 (2E1) is inducible by chronic ethanol consumption that results in enhanced activation of anesthetics and commonly used drugs (such as acetaminophen) to hepatotoxins. Therefore, assessment of hepatic 2E1 is needed in prescribing these drugs for the management of alcoholic patients. Currently, measurement of 2E1 requires either immunohistochemistry on frozen sections or Western blot (WB) analysis of homogenized tissue in excess of that needed for pathology. To obtain a more widely applicable method, we developed a procedure to detect 2E1 by immunohistochemistry in formalin-fixed, paraffin-embedded liver biopsies obtained routinely for diagnosis. Data were collected from rats fed ethanol-containing or control liquid diets for 3 weeks. Immunostaining was performed using anti-human rabbit 2E1 antibody as the primary antibody, and the immunoreaction was detected by the avidin-biotin immunoperoxidase method after treating sections with target unmasking fluid, an antigen retrieval buffer that enhanced the staining of 2E1. In control rats, 2E1 staining was weak and perivenular. After ethanol feeding, it showed a lobular gradient, strongest perivenular and weakest periportal, similar to that seen in frozen sections. The staining intensity was scored as: 0 (no staining) to 3 (strong staining). The zonal staining was scored as follows: 1 = perivenular zonal staining, 2 = midzonal, and 3 = panlobular. With the product of the two scores, a significant difference was found between alcohol-fed and control rats (5.1 +/- 0.3 vs. 0.8 +/- 0.2, p < 0.001). 2E1 assessments by WB were also significantly different for these rat pairs (68.5 +/- 2.1 vs. 7.9 +/- 0.8 arbitrary units/mg protein, p < 0.001), with a parallel increase of immunostaining scores and WB measurement of 2E1 content. This immunohistochemical method was then validated in 14 paraffin-embedded percutaneous human liver biopsy samples. In livers of nonalcoholics, 2E1 staining was seen in the perivenular zone only, whereas in samples of alcoholics, the staining was perivenular to midzonal and sometimes periportal. A significant correlation between the zonal staining scores (rs = 0.67, p < 0.005) or intensity x zonal staining scores (rs = 0.79, p < 0.001) and WB analysis was found. The immunohistochemical assessments of 2E1 expression in formalin-fixed, paraffin-embadded sections from livers of alcoholics was found to correlate with WB analysis, and lobular distribution was consistent with that seen in frozen sections. The proposed method should therefore be useful for the assessment of 2E1 content in paraffin-embedded liver samples, thereby aiding in the management of heavy drinkers.

Activity-independent segregation of excitatory and inhibitory synaptic terminals in cultured hippocampal neurons

Cultured hippocampal neurons were used as a model system to address experimentally the spatial and temporal sequence leading to the appropriate sorting of excitatory and inhibitory synaptic terminals to different cellular target domains and the role of neural activity in this process. By using antibodies against glutamic acid decarboxylase 65 (GAD65) and synaptophysin, we examined the development and segregation of GABAergic and non-GABAergic synaptic terminals on single neurons. Electron microscopy confirmed that GAD65-labeled swellings observed using light microscopy corresponded to synaptic boutons. From the time at which GABAergic terminals first appeared, they developed at a more rapid rate on neuronal somata than non-GABAergic terminals did, such that by 18 d in culture, 60% of the total boutons on somata were GABAergic. By contrast, the majority (70%) of boutons on dendrites were non-GABAergic. These data suggest that inhibitory synaptic terminals are targeted preferentially to or maintained on cell somata at the expense of excitatory terminals. Interestingly, non-GABAergic terminals were not inhibited from forming synapses on cell somata, because in the absence of GABAergic terminals they attained the same total somatic terminal density seen in the presence of GABAergic terminals. Chronic blockade of neuronal activity did not affect the differential targeting of GABAergic and non-GABAergic axons; however, it did reduce the extent of dendritic arborization. Our findings support a two-step model for synaptic segregation whereby the majority of terminals is initially targeted in an activity-independent manner to the appropriate cellular domains, but an additional developmental mechanism serves to further restrict and refine the original synaptic distribution.

Induction of cytochrome P-4502E1 by ethanol in rat Kupffer cells

Ethanol has been shown to affect several Kupffer cell functions, but the mechanisms underlying these changes are unknown. One possible mediator is cytochrome P-4502E1 (CYP2E1), an ethanol-inducible enzyme that has been associated with toxic effects in the liver, as well as in many extrahepatic organs. To assess whether CYP2E1 can be induced by ethanol in Kupffer cells, male rats pair-fed ethanol-containing or control Lieber-DeCarli diets for 3 weeks were studied. Immunoblotting experiments showed that ethanol-treatment caused a 7-fold increase in CYP2E1 content both in Kupffer cells and hepatocytes. When expressed per milligram of S9 protein, the content of CYP2E1 in Kupffer cells was, however, 10 times lower than in hepatocytes. Immunohistochemical studies revealed that CYP2E1 is located in the endoplasmic reticulum of Kupffer cells in vivo and that it is also present in isolated Kupffer cells. In both Kupffer cells and hepatocytes, ethanol feeding increased the hydroxylation of p-nitrophenol, a relatively specific substrate for CYP2E1, demonstrating that the induced CYP2E1 was catalytically active. This reaction was significantly inhibited by anti-CYP2E1 IgG in both types of cells. Although CYP2E1 may not be the predominant pathway for ethanol metabolism in hepatocytes, it is possibly the major one in Kupffer cells. Thus, the induction of CYP2E1 by ethanol in these cells could cause significant changes in intracellular acetaldehyde concentrations which, together with increased lipid peroxidation, may contribute to the development of alcoholic liver injury.

Antiviral activities of anthraquinones, bianthrones and hypericin derivatives from lichens

The antiviral activities of some naturally occurring anthraquinones, bianthrones, and hypericin derivatives were compared by the end-point CPE (viral cytopathic effects) method and plaque assays. Under optimal conditions of exposure to light, hypericin, 7,7'-dichlorohypericin and 5,7-dichloroemodin exhibited strong inhibitory activity against HSV-1 (herpes simplex virus type 1) in both assays. Partial inactivation of the virus was shown by emodin, 7-chloroemodin and 7-chloro-1-O-methylemodin; the bianthrones and other anthraquinones were found to be inactive. Antiviral activity appeared to be positively correlated with increasing substitution of chlorine in the anthraquinone structure. In the absence of light, only hypericin and 7,7'-dichlorohypericin displayed detectable activity.

Defective major histocompatibility complex class I expression in a sarcomatoid renal cell carcinoma cell line

We studied major histocompatibility complex (MHC) class I expression in 12 tumor cell culture lines established from patients with metastatic renal cell carcinoma (RCC). In one of these cell culture lines, UOK 123, we found no surface expression of beta 2-microglobulin (beta 2m) and MHC class I by flow cytometry. Immunofluorescence staining using three different monoclonal antibodies to beta 2m revealed no detectable beta 2m in the endoplasmic reticulum (ER), Golgi apparatus, cytoplasm, or on the cell surface. There was no evidence of folded class I molecules inside or on the surface of the cells; however, the ER stained intensively for unfolded class I molecules. Transient expression of beta 2m by UOK 123 after infection with a recombinant vaccinia virus containing the gene for beta 2m resulted in normal expression of both beta 2m and class I (HLA-A, B, C) determinants assessed by flow cytometry analysis. No expression of class I or beta 2m was seen with the recombinant vaccinia vector carrying a control gene. The inability of class I molecules to reach the cell surface is due to the requirement of beta 2m for proper folding and presentation of the class I MHC complex. The failure to assemble and express MHC class I complex on the cell surface renders these cells incapable of antigen presentation to cytotoxic T cells and provides a mechanism for escape from immune recognition by the tumor.