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1.
J Biol Regul Homeost Agents ; 34(4 Suppl. 3): 139-143. Congress of the Italian Orthopaedic Research Society, 2020.
Article in English | MEDLINE | ID: mdl-33261269

ABSTRACT

Despite the great advances of the technology in the joint prosthesis and the high execution rate of total knee arthroplasty (TKA), there are still about 15% of clinical unsatisfactory rate in this surgery. TKAs are currently performed using a mechanical alignment of the knee, correcting varus/valgus deformities with the purpose to achieve a longer implant survivorship, but this surgical technique results in an alteration of the normal knee kinematics. Nowadays, the idea to restore the pre-arthritic alignment of the knee with the goal to obtain a normal kinematics and better functional results becomes more and more consistent and the kinematic alignment (KA) was developed as alternative to the mechanical one. The aim of this preliminary study is to analyse the functional outcomes in patients who underwent KA-TKA in the short-term follow-up and to compare them with those obtained in patients treated by the mechanical alignment (MA) TKA. Therefore, skeletally mature patients, with no history of previous knee surgical procedures, who underwent isolated TKA for knee osteoarthritis, were included in this study. The patients were prospectively divided into two homogeneous groups according to the different surgical techniques performed (KA-TKA and MA-TKA groups). Clinical and functional scores (VAS, KOOS-PS, MCS-12, Final KSS, and Functional KSS) were collected pre- and postoperatively at a mean follow-up of 3 three months. As a result, 26 patients were included in the study, with a mean age of 69.3±7.61 years old (range: 55 - 84 years old). There were 38.5% male and 61.5% female. There were 13 patients in KA-TKA and 13 patients in MA-TKA. Three months after surgery each of the scores tested demonstrated statistically significant better outcomes in KA-TKA, compared to the MA-TKA group. MCS-12 resulted comparable in the two study groups. This preliminary study compares the short-term clinical and functional outcomes between KA and MA in total knee replacement. Further studies are required to confirm these results and to extend the sample size to obtain reliable clinical evidences.


Subject(s)
Arthroplasty, Replacement, Knee , Knee Prosthesis , Aged , Aged, 80 and over , Biomechanical Phenomena , Female , Humans , Knee Joint/surgery , Male , Middle Aged , Osteoarthritis, Knee/surgery , Range of Motion, Articular
3.
J Biol Regul Homeost Agents ; 32(6 Suppl. 1): 89-96, 2018.
Article in English | MEDLINE | ID: mdl-30644288

ABSTRACT

Total Hip Arthroplasty (THA) is considered the most successful treatment for advanced hip osteoarthritis. Different surgical approaches for THA are available and they have shown excellent outcomes in the long-term follow-ups. However, few studies have analyzed the functional outcomes in the first days after a THA surgery. The purpose of this study was to compare the early functional outcomes between two different surgical techniques: a minimally invasive direct anterior approach (mini-DAA) and a postero-lateral approach (PL). Twelve patients for each group were analyzed. Pre- and postoperative (3, 10, 30 and 90 days after surgery) Patient-Reported Outcome Measures (PROMs) were administered: HOOS, HHS, VAS and SF-12-v2 scores. Moreover, comparison between surgical operation time and blood loss were examined. PROMs showed a significant improvement in the SF-12-v2 in the mini-DAA group compared to the PL group at 3 days after surgery: this difference was maintained also after 10 and 30 days. In addition, HOOS and HHS were significantly ameliorated in the mini-DAA group starting 10 days from surgery. In both groups, a physiological pain reduction was observed in the first days after surgery; comparing it to the pre-surgical VAS values, we found a significant improvement in the scores for the mini-DAA group after 30 days. Moreover, we demonstrated a significant reduction in blood loss for the mini-DAA group. Surgical operation times were similar in the two groups; however, the duration of the mini-DAA procedure was shorter compared with the known literature. In this preliminary study, we demonstrated that the minimally invasive direct anterior approach for THA may lead to benefits in the early postoperative time, as it allows for an improvement in functional outcomes, a reduction of postoperative pain, a reduction of hospitalization time and consequent reduction of postoperative complications; therefore, this surgical approach may consent an early return to work and daily activities.


Subject(s)
Arthroplasty, Replacement, Hip/methods , Osteoarthritis, Hip/surgery , Humans , Treatment Outcome
4.
J Biol Regul Homeost Agents ; 32(6 Suppl. 1): 193-199, 2018.
Article in English | MEDLINE | ID: mdl-30644302

ABSTRACT

Articular cartilage injuries are still unsolved due to the limited intrinsic healing potential of this tissue. Unlike other tissues, inflammation in the synovial joint causes perpetual damage and progressively leads to the development of osteoarthritis. Previous in vitro and in vivo studies have demonstrated the efficacy of mesenchymal stem cells isolated from adipose tissue in modulating inflammation. In this study, we analyzed the role of these cells in modifying the pathological microenvironment present in knee osteoarthritis. This is an interventional, prospective, randomized, controlled study. Starting from June 2017, 39 patients with grade III and IV knee osteoarthritis of Kellgren-Lawrence were enrolled, aged between 45 and 75 years, with pain greater than or equal to 6 according to the VAS scale, without ligament instability, with an axial deviation not greater than 10° and with a BMI between 18 and 30. The control group underwent an arthroscopic debridement, while the experimental group underwent an arthroscopic debridement and a subsequent intra-articular injection of autologous micro-fragmented adipose tissue. Patients were evaluated before surgery and at 6 months after the procedure, by radiological analysis (MRI) and functional outcome measures. The main purpose of the study is to evaluate the symptomatic improvement by comparing the functional outcome scores between the two groups. At 6 months after treatment, preliminary results on 39 patients showed pain reduction and functional improvements in the experimental group without a significant difference due to the low number of patients. The radiological and biochemical analyses are still ongoing. To date, the study has not revealed any side effects. These preliminary results demonstrate an encouraging positive trend in the experimental group. Patient recruitment is still ongoing to finalize the statistical analyses and to confirm our hypothesis.


Subject(s)
Adipose Tissue/transplantation , Osteoarthritis, Knee/therapy , Aged , Arthroscopy , Debridement , Humans , Injections, Intra-Articular , Middle Aged , Prospective Studies , Transplantation, Autologous , Treatment Outcome
5.
J Headache Pain ; 18(1): 55, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28477307

ABSTRACT

BACKGROUND: Headache disorders are highly prevalent, and have a substantial and negative impact on health worldwide. They are largely treatable, but differences in structure, objectives, organization and delivery affect the quality of headache care. In order to recognize and remedy deficiencies in care, the Global Campaign against Headache, in collaboration with the European Headache Federation, recently developed a set of quality indicators for headache services. These require further assessment to demonstrate fitness for purpose. This is their first implementation to evaluate quality in headache care as a multicentre national study. METHODS: Between September and December 2016, we applied the quality indicators in six Italian specialist headache centres (Bologna, Firenze, Modena, Padova, Roma Campus Bio-Medico and Roma Sapienza). We used five previously developed assessment instruments, translated into Italian according to Lifting The Burden's translation protocol for hybrid documents. We took data from 360 consecutive patients (60 per centre) by questionnaire and from their medical records, and by different questionnaires from their health-care providers (HCPs), including physicians, nurses, psychologists and nursing assistants. RESULTS: The findings, comparable between centres, confirmed the feasibility and practicability of using the quality indicators in Italian specialist headache centres. The questionnaires were easily understood by HCPs and patients, and were not unduly time-consuming. Diagnoses were almost all (> 97%) according to ICHD criteria, and routinely (100%) reviewed during follow-up. Diagnostic diaries were regularly used by 96% of physicians. Referral pathways from primary to specialist care existed in five of the six clinics, as did urgent referral pathways. Instruments to assess disability and quality of life were not used regularly, a deficiency that needs to be addressed. CONCLUSION: This Italy-wide survey confirmed in six specialist centres that the headache service quality indicators are fit for purpose. By establishing majority practice, identifying commonalities and detecting deficits as a guide to quality improvement, the quality indicators may be used to set benchmarks for quality assessment. The next step is extend use and evaluation of the indicators into non-specialist care.


Subject(s)
Academic Medical Centers/standards , Headache Disorders/epidemiology , Headache Disorders/therapy , Health Personnel/standards , Quality Indicators, Health Care/standards , Tertiary Care Centers/standards , Adult , Female , Headache Disorders/diagnosis , Humans , Italy/epidemiology , Male , Referral and Consultation/standards , Surveys and Questionnaires
9.
Br J Cancer ; 86(11): 1776-85, 2002 Jun 05.
Article in English | MEDLINE | ID: mdl-12087466

ABSTRACT

CD10 constitutes a favourable prognostic marker for childhood acute lymphoblastic leukaemia. Since correlations between CD10, cell cycle and apoptotic abilities were demonstrated in various cell types, we investigated whether differences existed in the cycling/apoptotic abilities of CD10-positive and CD10-negative B acute lymphoblastic leukaemia cells. Twenty-eight cases of childhood acute lymphoblastic leukaemia (mean age of 6.8 years) were subdivided into two groups according to high (17 cases, 93.2+/-4.5%, MRFI 211+/-82 CD10-positive cells) or low (11 cases, 11.5+/-6.2%, MRFI 10+/-7 CD10-negative cells) expression of CD10. CD10-positive acute lymphoblastic leukaemia cells were cycling cells with elevated c-myc levels and propensity to apoptosis, whereas CD10-negative acute lymphoblastic leukaemia cells had lower cycling capacities and c-myc levels, and were resistant to apoptosis in vitro. A close correlation between all these properties was demonstrated by the observations that the few CD10-positive cells found in the CD10-negative acute lymphoblastic leukaemia group displayed elevated c-myc and cycling capacities and were apoptosis prone. Moreover, exposure of CD10-positive acute lymphoblastic leukaemia B cells to a peptide nucleic acid anti-gene specific for the second exon of c-myc caused inhibition of c-myc expression and reduced cell cycling and apoptotic abilities as well as decreased CD10 expression.


Subject(s)
Apoptosis , Cell Cycle/genetics , Chromosome Aberrations , Neprilysin/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Antigens, CD/analysis , Biomarkers/analysis , Bone Marrow Cells/pathology , Child , Humans , Karyotyping , Neprilysin/analysis , Polymerase Chain Reaction/methods , Precursor Cell Lymphoblastic Leukemia-Lymphoma/immunology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured
10.
Nat Med ; 7(7): 807-13, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11433345

ABSTRACT

Here we show that apoptotic cells overexpress vinculin and are ingested by dendritic cells, which subsequently cross-prime vinculin-specific cytotoxic T lymphocytes (CTLs). Successful cross-priming requires that the apoptotic cells provide maturation signals to dendritic cells through CD40-CD40 ligand (CD40L) interactions. If apoptotic cells are CD40L-, the help of a third T cell is needed for priming, indicating a regulatory role for apoptotic cells in determining priming or tolerance. Vinculin-specific CTL priming is also related to apoptosis in vivo, given that in HIV-seropositive individuals, the frequency of specific CTLs depends on the proportion of peripheral CD40L+ apoptotic cells.


Subject(s)
Apoptosis , Cross Reactions/immunology , T-Lymphocytes, Cytotoxic/immunology , Vinculin/metabolism , Amino Acid Sequence , Base Sequence , Cell Line , DNA Primers , Vinculin/chemistry , Vinculin/physiology
11.
Haematologica ; 85(3): 256-62, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10702813

ABSTRACT

BACKGROUND AND OBJECTIVE: gd T-cell lymphomas are only exceptionally observed in transplanted patients. Aim of this study was the detailed characterization of one such case. DESIGN AND METHODS: The patient developed spontaneous splenic rupture six years after kidney transplantation. The splenic red pulp was infiltrated by medium-sized and large lymphoid cells with two or more nucleoli. At autopsy, similar lymphoid cells infiltrated the hepatic sinusoids. Histologic, immunologic and molecular studies were carried out. RESULTS: By immunohistochemistry, the atypical lymphoid cells were found to express CD3, CD45 and CD43, indicating their T-lineage origin. Approximately 99% of spleen mononuclear cells (MNC) were CD3(+), gammadelta TcR+, CD4-, CD8-, alphabeta TcR-. A clonal gammadelta TcR rearrangement (Vgamma1-Jgamma1.3/2.3-Cgamma2; Vdelta1-Ddelta2-Jdelta1) was detected. The final diagnosis was peripheral T-cell lymphoma, hepato-splenic gammadelta-type. EBV infection of spleen MNC was documented by molecular studies. However, in situ hybridization for EBER-1 (EBV-RNA) showed that only a minority of malignant lymphoid cells (5-7%) were EBV-infected. INTERPRETATION AND CONCLUSIONS: It is concluded that EBV infection was as a late event involving an already transformed gd T-cell clone.


Subject(s)
Antigens, CD , CD3 Complex/blood , Epstein-Barr Virus Infections/blood , Kidney Transplantation/immunology , Liver Neoplasms/pathology , Lymphoma, T-Cell/classification , Lymphoma, T-Cell/immunology , Splenic Neoplasms/pathology , Adult , Cell Lineage , DNA, Viral/blood , Epstein-Barr Virus Infections/genetics , Gene Rearrangement, delta-Chain T-Cell Antigen Receptor/genetics , Humans , Leukocyte Common Antigens/blood , Leukosialin , Liver Neoplasms/immunology , Liver Neoplasms/virology , Lymphoma, T-Cell/virology , Male , Receptors, Antigen, T-Cell, gamma-delta/blood , Sialoglycoproteins/blood , Splenic Neoplasms/immunology , Splenic Neoplasms/virology
12.
Nat Biotechnol ; 18(3): 300-3, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10700145

ABSTRACT

Peptide nucleic acids (PNA) are synthetic homologs of nucleic acids in which the phosphate-sugar polynucleotide backbone is replaced by a flexible polyamide. In this study, a PNA construct was employed as an anti-gene agent in intact cells in culture. The cell lines studied were derived from Burkitt's lymphomas (BL) that presented a translocated and hyperexpressed c-myc oncogene. A 17-mer anti-myc PNA, complementary to a unique sequence located at the beginning of the second exon of the oncogene, and was covalently linked at its N terminus to a nuclear localization signal (NLS) (PNA-myc(wt)-NLS). When BL cells were exposed to PNA-myc(wt)-NLS, the anti-gene construct was localized predominantly in the cell nuclei and a rapid consequent downregulation of c-myc expression occurred. Under these conditions, both completion of a productive cell cycle and apoptosis were inhibited.


Subject(s)
Genes, myc/genetics , Nuclear Localization Signals/genetics , Peptide Nucleic Acids/pharmacology , Antigens, Polyomavirus Transforming/metabolism , Apoptosis , Cell Death , Cell Division/drug effects , Dose-Response Relationship, Drug , Down-Regulation , Flow Cytometry , Fluorescent Antibody Technique , Humans , Microscopy, Confocal , Nuclear Envelope/drug effects , Nuclear Envelope/metabolism , Plasmids , Proto-Oncogene Proteins c-myc/metabolism , Time Factors , Transfection , Tumor Cells, Cultured
13.
Blood ; 94(9): 3067-76, 1999 Nov 01.
Article in English | MEDLINE | ID: mdl-10556191

ABSTRACT

This study shows that human postthymic T cells express CD10 when undergoing apoptosis, irrespective of the signal responsible for initiating the apoptotic process. Cells from continuous T-cell lines did not normally express CD10, but became CD10(+) when induced into apoptosis by human immunodeficiency virus (HIV) infection and exposure to CD95 monoclonal antibody, etoposide, or staurosporin. Inhibitors of caspases blocked apoptosis and CD10 expression. Both CD4(+) and CD8(+) T cells purified from normal peripheral blood expressed CD10 on apoptotic induction. CD10 was newly synthesized by the apoptosing cells because its expression was inhibited by exposure to cycloheximide and CD10 mRNA became detectable by reverse transcription-polymerase chain reaction in T cells cultured under conditions favoring apoptosis. To show CD10 on T cells apoptosing in vivo, lymph node and peripheral blood T cells from HIV(+) subjects were used. These suspensions were composed of a substantial, although variable, proportion of apoptosing T cells that consistently expressed CD10. In contrast, CD10(+) as well as spontaneously apoptosing T cells were virtually absent in peripheral blood from normal individuals. Collectively, these observations indicate that CD10 may represent a reliable marker for identifying and isolating apoptosing T cells in vitro and ex vivo and possibly suggest novel functions for surface CD10 in the apoptotic process of lymphoid cells.


Subject(s)
Apoptosis/immunology , Neprilysin/biosynthesis , T-Lymphocytes/immunology , T-Lymphocytes/pathology , Cells, Cultured , Flow Cytometry , HIV Seropositivity/blood , HIV Seropositivity/immunology , Humans , Neprilysin/immunology
14.
Electrophoresis ; 20(4-5): 1092-7, 1999.
Article in English | MEDLINE | ID: mdl-10344290

ABSTRACT

In previous studies we described a patient with Burkitt's lymphoma and AIDS, whose cells recognized a molecule expressed by normal and malignant breast cells. In the present study, we identified this antigen by two-dimensional (2-D) electrophoresis and Western blotting using the antibody produced by lymphoma cells. The antigen so identified consisted of two clusters of spots with a molecular mass (Mr) of 60 and 50 kDa, respectively. Preparative immobilized pH gradient (IPG) was subsequently used to isolate the clusters of spots of higher molecular masses, from which peptide fragments of approximately 10 aa were separated on reverse-phase chromatography and sequenced. This procedure enabled the identification of the antigen recognized by the lymphoma cells as HSP-60. By means of serological analyses it was possible to identify the lower molecular mass cluster of spots as a molecule related to HSP-60. It is hypothesized that this molecule is a membrane form of HSP-60 that differs from HSP-60 in a COOH terminal portion.


Subject(s)
Antibodies, Neoplasm/immunology , Antigens, Neoplasm/immunology , Burkitt Lymphoma/immunology , Chaperonin 60/immunology , Electrophoresis, Gel, Two-Dimensional/methods , Immunoglobulin M/immunology , Lymphoma, AIDS-Related/immunology , Amino Acid Sequence , Antibodies, Monoclonal/immunology , Apoptosis/immunology , Epitope Mapping , Epitopes, B-Lymphocyte/immunology , Humans , Molecular Sequence Data , Tumor Cells, Cultured
15.
Cell Immunol ; 193(1): 80-9, 1999 Apr 10.
Article in English | MEDLINE | ID: mdl-10202115

ABSTRACT

Using immunofluorescence, RT-PCR, and Western blotting, we have demonstrated the ability of human B cells to express CD4. In each of the 10 lymphoblastoid cell lines (LCL) tested there was variable, but definite, proportion of CD4-positive B cells. Expression of CD4 was related to the cell cycle; CD4 was expressed in the G1 phase and continued at later phases of the cell cycle. CD4 was in part internalized and degraded by the LCL B cells. Surface CD4 was associated to lck and its crosslinking resulted in tyrosine phosphorylation. Additional experiments conducted on freshly prepared tonsillar B cells demonstrated that CD4 was expressed by large activated B cells, but not by small resting B cells. However, not all the activated tonsillar B cells had surface CD4 since germinal center cells were CD4-negative. Crosslinking of CD4 on LCL or on tonsillar activated B cells resulted in apoptosis in vitro, a finding that indicates the capacity of CD4 to deliver functional signals to B cells and to play a regulatory function in their physiology. Exposure of CD4 expressing B cells to gp120 under conditions that resulted in CD4 crosslinking also caused apoptosis suggesting some implications for the pathophysiology of AIDS.


Subject(s)
Apoptosis , B-Lymphocytes/physiology , CD4 Antigens/physiology , Lymphocyte Activation , CD4 Antigens/analysis , Cell Cycle , Cell Line , HIV Envelope Protein gp120/physiology , Humans , Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/analysis
17.
Eur J Immunol ; 27(1): 234-8, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9022024

ABSTRACT

In this study, we investigated the c-myc expression by tonsillar germinal center (GC) B cells using reverse transcriptase-polymerase chain reaction, flow cytometry, Western blot and in situ immunohistochemical methods. The results obtained demonstrate elevated levels of c-myc mRNA and of Myc protein in GC B cells compared to those of the other resting or activated tonsillar B cells. Separation of GC B cells into centroblasts and centrocytes revealed that, while differing in their cell cycle status, surface marker expression and morphology, the two cell types had the same propensity to apoptosis and elevated Myc protein expression, thus reinforcing the notion of a close correlation between these two events. Based upon these observations and other considerations it is proposed that elevation of Myc proteins confers to GC B cells a particular propensity to apoptosis, while the subsequent decision between progression into the cell cycle or programmed cell death is dictated by other signals that are delivered in the GC and perhaps operate at the level of other proto-oncogenes.


Subject(s)
Apoptosis , B-Lymphocytes/immunology , Germinal Center/cytology , Proto-Oncogene Proteins c-myc/genetics , Cell Cycle , Gene Expression , Humans , Palatine Tonsil/cytology , RNA, Messenger/genetics , Trihexosylceramides/analysis
18.
Int J Cancer ; 68(6): 810-6, 1996 Dec 11.
Article in English | MEDLINE | ID: mdl-8980188

ABSTRACT

Normal EBV-positive lymphoblastoid B-cell lines (LCL) were transfected with vectors containing the c-myc oncogene (pHEBO-E(mu)-myc) or control vectors (pHEBO-E(mu)) and analyzed for the expression of EBV-lytic and latent antigens. While EBV-latent antigens were normal in the c-myc transfectants, there was an almost complete downregulation of EBV-lytic antigens, including BZLF1, EA(D), gp340 and VCA. These observations were consistently repeated on 6 different LCLs transfected with c-myc. Unlike control LCLs, the c-myc transfectants did not release infectious EBV. PCR analysis demonstrated that BZLF1 mRNA was virtually absent in c-myc transfectants, possibly suggesting that the deregulated c-myc imposed a block in the EBV-lytic cycle at this particular level. c-myc transfectants failed to sustain the proliferative response of autologous CD4+ T-cell clones with specificity for EBV-lytic antigens. However, they regained this capacity after incubation with ultraviolet-inactivated EBV or gp340 antigen in vitro, also indicating that their antigen-presenting capacities were not impaired. c-myc transfectants failed to elicit a secondary proliferative response by autologous CD4+ T cells purified from the peripheral blood of EBV-seropositive donors. Exposure of c-myc transfectants to UV-inactivated EBV again resulted in a proliferative CD4+ T-cell response comparable to that elicited by the control LCLs. Collectively, our data provide evidence for the remarkable ability of an oncogene to influence the life cycle of a virus and to modify the antigenicity of the infected cells.


Subject(s)
B-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/physiology , Down-Regulation , Genes, myc/immunology , Herpesvirus 4, Human/immunology , B-Lymphocytes/physiology , Blotting, Western , Cell Division/physiology , Cell Line , Humans , Immunologic Memory/physiology , Transfection
19.
Blood ; 88(2): 599-608, 1996 Jul 15.
Article in English | MEDLINE | ID: mdl-8695808

ABSTRACT

In a previous study, we described a cell line (BRG-P) derived from a woman with Burkitt's lymphoma (BL) and acquired immunodeficiency syndrome that shared the same characteristic cytogenetic abnormalities as the patient's malignant cells. This cell line contained subclones that displayed an isotype switch from IgM to IgA1 and an accumulation of point mutations in the Vh region genes. Because these two features suggested an antigen-driven process, we began a search for the antigen responsible for the stimulation of the malignant B cells. Specifically, we hypothesized that because the patient's tumor had presented as a lymphomatous infiltration of the breast, the malignant B cells were recruited to this site because of the reactivity of their surface lg with breast tissue. A hybridoma (BRG-H) was obtained by fusing BRG-M cells (an IgM producing subclone of the BRG-P cell) with an appropriate cellular partner. The monoclonal antibody (BRG MoAb) produced by this hybridoma reacted strongly with two of five breast cancer cell lines and stained normal and malignant ductal epithelial cells on breast tissue sections. The antigen recognized by the BRG MoAb consisted of a single, minimally glycosylated polypeptide chain of 45 kD (p45). The BRG MoAb failed to react with a panel of human cell lines from different tissues, except for one cell line from a uterine cervical carcinoma. No reactivity was detected for a panel of exogenous antigens from various pathogens, including human immunodeficiency virus and self-antigens frequently recognized by polyspecific antibodies. Experiments were performed to investigate the functional consequences of the interaction of surface IgM with its specific ligand. Coculture of BRG-M cells with p45+, but not with p45-, breast cells caused apoptosis of BRG-M cells. The specificity of the interaction was shown by the observation that apoptosis was prevented by pretreatment of BRG-M cells with a monovalent F(ab') fragment of rabbit IgG antibody to human mu chains. Moreover, only BRG-M cells, but not other BL cells, underwent apoptosis after exposure to p45+ breast cells. The interaction between the CD40 molecule expressed by BRG-M cells and its specific ligand (CD40L) prevented p45-induced cell apoptosis. Because this interaction mimics that occurring in vivo between T and B cells during immune responses, our data suggest that various events contributed to the emergence of the BL, in this particular patient, including antigenic stimulation possibly assisted by T-cell help.


Subject(s)
Antigens, Neoplasm/immunology , Apoptosis/physiology , Autoantigens/immunology , Breast Neoplasms/pathology , Burkitt Lymphoma/pathology , Cell Transformation, Neoplastic/immunology , Immunoglobulin M/immunology , Isoantigens/immunology , Lymphoma, AIDS-Related/pathology , Neoplasm Proteins/immunology , Receptors, Antigen, B-Cell/immunology , Adult , Animals , Antibodies, Monoclonal/immunology , Antigen-Antibody Reactions , Breast/immunology , Breast Neoplasms/immunology , Burkitt Lymphoma/immunology , CD40 Ligand , Carcinoma, Ductal, Breast/pathology , Coculture Techniques , Epithelium/immunology , Female , Humans , Hybridomas/immunology , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Lymphoma, AIDS-Related/etiology , Lymphoma, AIDS-Related/immunology , Membrane Glycoproteins/physiology , Models, Biological , Rabbits , Tumor Cells, Cultured
20.
J Exp Med ; 181(2): 699-711, 1995 Feb 01.
Article in English | MEDLINE | ID: mdl-7836923

ABSTRACT

Activated c-myc gene was introduced into the cells of three normal Epstein-Barr virus (EBV)-positive lymphoblastoid B cell lines (LCL). The cells were monitored for the appearance of new phenotypic and functional features compared with the control LCL cells transfected with plasmid that did not contain the c-myc gene. The LCL-expressing c-myc constitutively did not arrest growth in low serum concentration. However, the cell number in the cultures failed to increase because of substantial cell death. Death was due to apoptosis as demonstrated by flow cytometric analysis of propidium iodide-stained cells, by typical DNA laddering in gel electrophoresis, and by the inspection of Giemsa-stained cell smears. Apoptosis was also induced by exposing the transfected cells to antibodies directed to the immunoglobulin mu chain (a-mu-ab) irrespective of the serum concentration in the culture. Exposure of the cells to CD40 ligand (CD40L) or CD40 monoclonal antibody prevented cell apoptosis. Upon transfection with c-myc, the LCL cells acquired a vacuolated morphology that was never observed in control cells. Moreover, the expression of CD10 and CD38 was upregulated, while that of CD39 and especially CD23 was downregulated. Unlike that observed in certain Burkitt lymphoma (BL) cell lines that share the same surface phenotype (CD10+CD38+CD23-CD39-), the c-myc-transfected cells expressed lymphocyte function-associated (LFA) 1, LFA-3, and intercellular adhesion molecule 1 and grew in large clumps rather than single-cell layers. Expression of CD10 and CD38 was particularly evident on the cells undergoing apoptosis, thus suggesting a correlation between the presence of these markers and the apoptotic process. Cells placed in conditions favoring in vitro apoptosis displayed downregulation of Bcl-2 protein. Bcl-2 expression was, however, upregulated when the cells were exposed to CD40L. These data indicate that the B cells expressing c-myc constitutively acquire some of the features of normal centroblasts and of BL cells, including the expression of CD10 and CD38, and the propensity to undergo apoptosis, which can be prevented by exposure to CD40L. Therefore, these cells can serve as a model system to study both BL lymphomagenesis as well as the process of B cell selection occurring in the germinal centers.


Subject(s)
Antigens, CD , B-Lymphocytes/virology , Burkitt Lymphoma/pathology , Genes, myc , Herpesvirus 4, Human , ADP-ribosyl Cyclase , ADP-ribosyl Cyclase 1 , Antigens, Differentiation/genetics , Apoptosis/genetics , B-Lymphocytes/pathology , Base Sequence , Burkitt Lymphoma/genetics , Burkitt Lymphoma/immunology , Cell Differentiation , DNA Primers , Down-Regulation , Herpesvirus 4, Human/isolation & purification , Humans , Membrane Glycoproteins , Molecular Sequence Data , Neprilysin/genetics , Phenotype , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-bcl-2 , Transfection , Tumor Cells, Cultured
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