Associations between HLA class I alleles and the prevalence of nasopharyngeal carcinoma (NPC) among Tunisians.

The high prevalence of nasopharyngeal cancer (NPC) in Southern Asia and Mediterranean Northern Africa suggests genetic predisposition among other factors. While Human Leukocyte Antigen (HLA) haplotypes have been conclusively associated with NPC predisposition in Asians, Northern African Maghrebians have been less intensely studied. However, low resolution serological methods identified weak positive associations with HLA-B5, B13 and B18 and a negative with HLA-B14. Using sequence based typing (SBT), we performed a direct comparison of HLA class I frequencies in a cohort of 136 Tunisian patients with NPC matched for gender, age and geographical residence to 148 normal Tunisians. The bimodal age distribution of NPC in Maghrebians was also taken into account. HLA frequencies in normal Tunisians were also compared with those of Northern Moroccan Berbers (ME) to evaluate whether the Tunisian population in this study could be considered representative of other Maghrebian populations. HLA-B14 and -Cw08 were negatively associated with NPC (odd ratio = 0.09 and 0.18 respectively, Fisher p(2)-value = 0.0001 and = 0.003). Moreover, positive associations were observed for HLA-B-18, -B51 (split of -B5) and -B57 (p(2)-value < 0.025 in all) confirming previous findings in Maghrebs. The HLA-B14/Cw*08 haplotype frequency (HF) was 0.007 in NPC patients compared to 0.057 in both Tunisian (OR = 0.12; p(2)-value = 0.001) and Moroccan controls. This study confirms several previous associations noted by serologic typing between HLA class I alleles and the prevalence of NPC in Maghrebians populations. In addition, we identified a putative haplotype rare in Tunisian patients with NPC that may serve as a genetic marker for further susceptibility studies.

Public epitope specificity of HLA class I antibodies induced by a failed kidney transplant: alloantibody characterization by flow cytometric techniques.

BACKGROUND: Patients whose kidney grafts fail develop alloantibodies that react with many HLA molecules. We analyzed the epitope specificity of HLA class I alloantibodies in the sera of 55 patients who had been sensitized by kidney grafts, and investigated the immunogenicity of various polymorphic epitopes. METHODS: HLA class I alloantibodies were detected and characterized by flow cytometry (FlowPRA beads). Potential "immunizing epitopes" were identified by comparing the amino acid sequences of HLA class I antigens/alleles of the donor, recipient and the antibody-reactivity pattern. RESULTS: In the 55 anti-HLA class I-positive patients, 82 different antibody reactivity patterns were identified; all but 5 (94%) were determined by a "public epitope" of donor HLA-A and/or -B molecules. Forty-five of 50 patients who showed HLA-A Res-MMs with their donors produced HLA-A antibodies, but only 31 of 51 subjects with HLA-B Res-MMs produced HLA-B antibodies (P=0.001; O.R.=5.81). The antibody patterns were specific for a "single" epitope of the mismatched donor molecules in 91% of patients. Forty-three of the 120 (36%) mismatched HLA-A and/or -B epitopes were positively correlated with antibody production. The polymorphic determinants of higher immunogenic capacity were b80N (Bw6-associated) and ab82-83LR (Bw4-associated) public epitopes. CONCLUSIONS: The humoral immune response against a kidney graft mainly produces HLA class I antibodies specific for "public epitopes" of mismatched donor molecules. A "single" donor-epitope may determine the production of a spread antibody pattern. In renal transplantation, epitope matching is better than HLA antigen matching for avoiding or minimizing development of HLA antibodies.

Susceptibility to Guillain-Barré syndrome is associated to polymorphisms of CD1 genes.

Guillain-Barré syndrome (GBS) is the prototype of a postinfectious autoimmune neuropathy. Molecular mimicry between glycolipid antigens expressed by an infective antigen such as Campylobacter jejuni and the human peripheral nerve has been hypothesized to be the causative mechanism of GBS. However, only 1/1000 of C. jejuni enteritis develops GBS. This emphasizes the importance of host-related factors in the development of the disease. HLA studies in GBS failed to show an association or gave conflicting results but MHC class I and II process and present peptides to T lymphocytes making unlikely that the HLA system plays a role in GBS with autoantibodies against self-gangliosides. CD1 molecules are MCH-like glycoproteins specialized in capturing and presenting a variety of glycolipid to antigen-specific T cells. There are five closely linked CD1 genes in humans located in chromosome 1 (named CD1A, B, C, D, and E) all showing limited polymorphism in exon 2 which codifies for the alpha1 domain of CD1 molecules. The nucleotide substitutions in CD1B and CD1C are rare and reported to be silent. In 100 controls and 65 GBS patients (21 with a recent C. jejuni infection and 35 with anti-glycolipid antibodies) we used direct sequencing by polymerase chain reaction to genotype exon 2 of CD1A, CD1D and CD1E genes. CD1D is monomorphic in both controls and patients whereas CD1A and CD1E are biallelic in exon 2. Subjects with CD1E*01/01 genotype are 2.5 times more likely to develop GBS, whereas subjects with CD1A*01/02 or CD1E*01/02 have a reduced relative risk by 3.6 and 2.3 times respectively. The combination of CD1A*01/02 and CD1E*01/02 reduces by 5 times the risk of developing GBS. Although a correlation between CD1E*01/01 genotype and recent C. jejuni infection or presence of antiganglioside antibodies was not found the overall findings indicate that susceptibility to develop GBS is associated with polymorphisms of CD1E and CD1A genes.

Are immunological mechanisms involved in colon cancer and are they possible markers for biotherapy improvement?

This paper focuses on our data on colon cancer patients. Our overall results lead us to believe that the suppressive effect of specific cytokines in colon cancer patients alters the functionality of TH1 and TH2 subsets of CD4+ T-cells, with an expansion of TH2 cells and a malfunctioning of TH1 cells. This immunological disregulation appears to increase with stage progression, suggesting a direct role in the mechanisms that allow the tumour to locate and expand within the host. It is also clear that in order to identify disease markers and generate an in vivo immune response that corrects the imbalance between TH1 and TH2 cells, we need to understand how tumour mechanisms cause this imbalance to begin with.

The study of a patient's immune system may prove to be a useful noninvasive tool for stage classification in colon cancer.

Therapy, and, therefore, prognosis, is strictly related to cancer stage, and hence, screening tests that can contribute to the early classification of disease stage represent a step forward in treatment. Unfortunately, few prognostic indices are available, especially noninvasive ones. Our study of the physiological network of the immune response, however, leads us to believe that it may well be possible to define immunological indices for the classification of cancer stage using blood parameters. In this paper, we show how the study of a patient's immune system can be used as a noninvasive tool for early-stage classification.

Colon cancer and gene alterations: their immunological implications and suggestions for prognostic indices and improvements in biotherapy.

Studies have shown that changes occur in c-Ki-ras, p53, and Bcl2 gene structure and function during the various stages of human colon carcinogenesis. Alterations of these genes are responsible for the establishment of a state of continuous stimulus for cell division and apoptotic inhibition at physiological and pharmacological levels. This paper focuses on the results of our research aimed at investigating how these gene alterations influence tumoral mechanisms on an immunological level and how immunological parameters can be used as prognostic markers for the passage of normal tissue to adenoma and adenoma to carcinoma. Overall, our data suggest that an alteration in the c-Ki-ras gene results in a switch to a suppressive type of immune response, determining an impairment of immune cell activation at both antigen- presenting-cell and T-cell levels. c-Ki-ras gene mutations, p53 deletions, and Bc12 expression, on the other hand, can be used as prognostic markers for the passage of normal tissue to adenoma and adenoma to carcinoma. The p53 oncogene does not appear to impair patients' immunological response further. In conclusion, an evaluation of c-Ki-ras, rather than p53 gene alterations, would seem to be more relevant in colon cancer prevention programs and biotherapy improvement.

Transient maintenance in bioreactor improves health of neuronal cells.

To examine whether a neuronal cell suspension can be held in vitro for a relatively short period without compromising survival rates and functionality, we have set up an experimental protocol planning 24 h of suspension culture in a rotary wall vessel (RWV) bioreactor before plating in a conventional adherent system. Apoptosis measurement and activated caspase-8, -9, and -3 detection have demonstrated that survey of the cells was not affected. The activity of major antioxidant enzymes (AOE), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), was significantly decreased in RWV-maintained cells. A significant decrease of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) is coupled with a level of activated nuclear factor-kappaB (NF-kappaB) protein significantly lower in RVW cells than in the control. On the contrary, the level of IL-6 expression did not change between the test and the control. A significant up-regulation of growth-associated protein-43 (GAP-43), peroxisome proliferator-activated receptor-beta/delta (PPARbeta/delta), and acyl-CoA synthetase 2 (ACS2) in RWV cells has been detected. We provide the evidence that primary neuronal cells, at an early stage of development, can be maintained in a suspension condition before adherent plating. This experimental environment does not induce detrimental effects but may have an activator role, leading cells to development and maturation in a tridimensional state.

MICA polymorphism in a population from north Morocco, Metalsa Berbers, using sequence-based typing.

The MICA gene encodes a family of nonclassical major histocompatibility complex class I molecules. Data on MICA polymorphism in different populations are still limited. In the present study, MICA allele frequencies (af) were assessed in 82 unrelated healthy individuals from a Moroccan Berber population named Metalsa (ME) by means of sequence-based typing of exons 2, 3, 4, and 5. In consideration of the linkage disequilibrium existing between MICA and human leukocyte antigen (HLA) class I alleles, MICA/HLA-B, MICA/HLA-Cw, and MICA/HLA-A haplotype frequencies (hf) were estimated. A wide allelic distribution including 16 different MICA alleles was found in ME. The most common MICA alleles were MICA*00801 (af = 0.268), *004 (0.232), *00902 (0.140), *00901 (0.085), and *00901 (0.073). The most common MICA/HLA-B haplotypes were MICA*004-B*4403 and MICA*009-B*50 (hf = 0.113 for both these haplotypes). Some known MICA and HLA-B associations were confirmed in this population. Noteworthy was the high frequency of MICA*009 (af = 0.226); the high frequency of B*50 found in ME (af = 0.114) permitted us to evidence the associations of MICA*00902 with B*5001 (hf = 0.068) or *5002 (hf = 0.045), whereas MICA*00901 was mainly associated with B*5101 (hf = 0.038), which corresponds to the previously described association MICA*009/A6-HLA-B*51. This study extends the previous knowledge on MICA polymorphism to a North African white population and may have implications for disease associations and transplantation.

Sequence-Based analysis of the HLA-DRB1 polymorphism in Metalsa Berber and Chaouya Arabic-speaking groups from Morocco.

To examine the genetic diversity in Morocco, the polymorphism at the HLA-DRB1 locus was investigated in two populations: the Metalsa group consisting of Berbers from north Morocco (who speak the Tarifit language and live in the Nador area), and the Chaouya group who are Arabic-speaking people from west Morocco (Atlantic coast) living in the Settat area. The DRB1 alleles of 197 healthy unrelated individuals were identified by direct DNA sequencing of exon 2 using fluorescently-labeled primers. A total of 28 and 29 alleles at DRB1 locus were identified in the Metalsa and Chaouya groups, respectively. The most frequent alleles in the Metalsa group are DRB1*03011 (20.2%), DRB1*0701 (12.12%), and DRB1*1302 (11.11%). In the Chaouya group, DRB1*0701 (16.33%), DRB1*15011 (12.76%), and DRB1*03011 (11.73%) are most common. Each population exhibits some specific variants and some uncommon alleles. The frequency of the DRB1*03011 allele differs significantly between the two populations (p = 0.0311). The DRB1 frequency distributions in the two groups suggest the effects of balancing selection. The interpopulation analysis highlighted a strong relatedness, based on genetic distances, between the two Moroccan groups and the other north Africans (the Moroccans from El Jadida area, Moroccan Souss Berbers, Algerians, and Tunisians), and to a lesser extent with the Iberians, French, and Ethiopians.

CD30 antigen: not a physiological marker for TH2 cells but an important costimulator molecule in the regulation of the balance between TH1/TH2 response.

Understanding the physiological role of CD30 would be an important step forward in transplants because CD30+ T cells can be induced by alloantigens even in the presence of immunosuppressives such as cyclosporine (Csa) and hence can act as regulatory cells in allograft. The results of functional studies on purified T CD30+ cell populations led us to hypothesize that the CD30 costimulator molecule is not a specific marker for TH2 cells in normal conditions, as has been suggested, but rather a marker for an important immunoregulatory subpopulation that regulates the balance between TH1 and TH2 (TH1/TH2) type response. To substantiate this hypothesis we studied the TH1/TH2 cytokine network in peripheral whole blood cultures stimulate with M44 CD30 ligand (CD30L), an agonistic monoclonal antibody (mAb). Four types of whole blood culture were used: the first had been stimulated with anti-CD3 mAb which generates a CD30 cytokine profile similar to alloreactive stimulation; the second with anti-CD3 mAb+M81 (an anti-CD30L mAb) to inhibit CD30/CD30L interaction; the third with anti-CD3+anti-interleukin (IL)4 mAbs to counteract IL4 activity and the fourth with anti-CD3+anti-interferon (IFN)gamma mAbs to counteract IFNgamma activity. Network interactions between soluble CD30 (sCD30, a maker of CD30 expression), sBcl2 (a marker of cell survival) and TH1/TH2 cytokines (IFNgamma, IL2, IL12p70, IL12p40, IL4, IL5 and IL10) were then studied in the supernatants obtained. Our results confirm the hypothesis above by showing that CD30 signals trigger functional mechanisms responsible for changes in levels of production of several important TH1 and TH2 cytokines involved in the regulation of the physiological balance between TH1/TH2 functions. The CD30-stimulated network, in fact, induces IFNgamma production linked to TH1 activity (-->TH1) which is subsequently integrated by IL4 production linked to TH2 activity (-->TH2). This production appears to be regulated, respectively, by IL12p40 (-->TH2) and IL12p70 (-->TH1) production which could maintain the balance between TH1/TH2 type response (TH1<-->TH2). Further CD30 mechanisms are the regulation of the interactions between: IL5-IFNgamma, IL5-IL4, IL2-IL10, IL2-IL12p40 and IL10-IL12p70 production. The immunoregulatory activity of CD30 was confirmed by the lack of production balance between the above-mentioned cytokines observed in cultures in which the interaction between CD30 and its natural ligand (CD30/CD30L) and IL4 or IFNgamma activity had been blocked. We therefore conclude that CD30 may be an important costimulatory molecule and marker for the physiological balance between TH1/TH2 immune response. Consequently, further study of CD30 immunoregulatory mechanisms may allow for the identification of methods for re-establishing equilibrium and hence more effective strategies for the prevention and treatment of immunopathological conditions such as transplant rejection.

Differential modulation of interleukin-6 expression by interleukin-1beta in neuronal and glial cultures.

We analysed the specific effects of IL-1beta immunoneutralization on the expression of IL-6 in different pure cultures of neurones and glia after both experimental subliminal hypoxia and recovery. Whereas the IL-1beta-deprivation signal induced a decrease in IL-6 expression and release of normoxic neurones, it provoked an increase in IL-6 protein in hypoxic neurones. Moreover, the direct correlation between IL-1beta and IL-6, observed in normal and recovering neuronal cultures, was reversed in hypoxic conditions. These reversals were not observed in glial cells, in which IL-1beta immunosuppression led to a decrease in IL-6 under all conditions considered. In conclusion, the IL-1beta modulates IL-6 in different ways according to the ambient physiological or pathological conditions, and also acts via different mechanisms, depending on the cellular phenotype.

IFNbeta-1a treatment and reestablishment of Th1 regulation in MS patients: dose effects.

The authors evaluated the relationships between clinical and pharmacologic parameters and the Th1/Th2/Th3 cytokine network in patients with relapsing-remitting multiple sclerosis treated with differing doses of interferon-beta1a (IFN-beta1a). Their results show that low doses are ineffective but that high doses restore Th1 regulation of the maturation and activation of monocytes, T cells, immature dendritic cells, dendritic cells, and T regulatory cells for central and peripheral self-tolerance. Interaction between interleukin (IL)-10, IL-12 p70, and IL-6 production appears to play an important role in the control of the maturation and activation states of dendritic cells and T regulatory cells, and is at the basis of the benefit of high doses. The results also indicate that the physiologic mechanisms involved in aging help immunologic reestablishment in IFNbeta-1a-treated patients. Finally, it would appear that the failure of IFNbeta-1a therapy to resolve multiple sclerosis completely is due to the suppression of IL-12 p70 mechanisms (responsible for the physiologic deletion of self-reactive cells) in activation conditions, probably by IFNbeta-1a itself.

Passage from normal mucosa to adenoma and colon cancer: alteration of normal sCD30 mechanisms regulating TH1/TH2 cell functions.

The pathogenesis of cancer is currently under intensive investigation to identify reliable prognostic indices for the early detection of disease. Adenomas have been identified as precursors of colorectal cancer and tumor establishment, and disease progression has been found to reflect a malfunction of the immune system. On the basis of the role of the CD30 molecule in the regulation of TH1/TH2 functions and our previous results, strongly suggesting the validity of serum TH1/TH2 cytokines in the study of tumor progression, we studied network interaction between the production of soluble (s) CD30/sBCl2 in whole blood culture [in basic conditions and after PHA, LPS, and anti-CD3 monoclonal antibody (mAb) stimulation] and levels of TH1/TH2 cytokines (IL2, IFN gamma, IL12, IL4, IL5, IL10). Peripheral blood from a group of healthy subjects, as well as from patients with adenoma and colorectal cancer was used. Our objective was to gain a better insight into the role of the CD30 molecule in the passage from normal mucosa to adenoma and tumor and identify specific disease markers. Our results suggest that the decrease in CD30 expression and the abnormal increase in Bcl2 expression, observed in the peripheral cells of both adenoma and tumor groups determine an imbalance between TH1/TH2 functions. Consequently, changes in sCD30/sBcl2 culture production and TH1/TH2 cytokine serum levels may be reliable markers for tumor progression. In fact, our overall data show that a decrease of sCD30 levels in basic and PHA conditions and an increase of IFN gamma, IL4, IL5, and IL12 serum levels and sBcl2 in all activation condition are indicative of the passage from normal mucosa to adenoma; whilst a decrease of sBcl2 level in basic, LPS and anti-CD3 conditions and of IL2, IFN gamma serum levels, together with an increase of IL5 are indicative of the passage from adenoma to tumor.

Peripheral blood immunological parameters for use as markers of pre-invasive to invasive colorectal cancer.

In cancer, the extent to which the disease has spread is probably the most important factor in determining patient prognosis. Hence practical and non-invasive methods are needed to identify disease stage. In a previous paper we showed how diagnostic and prognostic indices for disease progression could be defined by evaluating parameters in peripheral blood. The aim of this study was to identify further serum parameters that could be used. Serum levels of interferon (IFN) gamma, interleukin (IL)4, IL8, IL7, IL1 beta, tumor necrosis factor (TNF) alpha, granulocyte macrophage-colony stimulating factor (GM-CSF), soluble (s) IL2 receptor (R) and sIL6R were studied but only levels of IL4, sIL2R, IL8 and IL7 were found to be significant and would therefore be of use in defining diagnostic and prognostic indices for disease progression. In further detail, our results indicate that when serum levels of sIL2R < 522 U/ml, IL4 < 159 pg/ml and IL8 > 339 pg/ml there is a 95% probability that the disease is in stage I or II where there is no infiltration of lymph nodes; when serum levels of sIL2R > or = 522 Ug/ml, 159 pg/ml < or = IL4 < or = 319 pg/ml, and IL7 < 54 pg/ml, there is a 95% probability that the disease is in stage III and the tumor has invaded the lymph nodes; when the serum levels of IL4 > or = 431 pg/ml and IL7 > or = 54 pg/ml, there is a 95% probability that the disease is in stage IV and there is metastasis.

Post-transplant development of C1q-positive HLA antibodies and kidney graft survival.

The development of de novo human leukocyte antigen (HLA) donor specific antibodies (DSA), detected by both cytotoxic or solid phase assays, was considered the major risk factor for allograft failure in kidney transplantation. However, it was shown that not all patients with persistent production of DSA suffered loss of their grafts. Modified Luminex-Single Antigen assays, able to identify C1q-fixing antibodies, represent a new strategy in assessing the clinical relevance of detected DSA. This study demonstrated that C1q-fixing capability of de novo DSA is a clinically relevant marker of worse outcome and inferior graft survival in kidney transplantation. In fact, our findings evidenced a very low graft survival only in the patients who developed DSA able to fix C1q during post-transplant course, while patients producing C1q-negative DSA had good graft survival, which was comparable to that found in our previous study for DSA-negative patients. Moreover, anti-HLA class II antibodies had a higher incidence than anti-HLA class I, and the ability to fix C1q was significantly more frequent among anti-DQ DSA than anti-DR DSA. Monitoring of de novo C1q-DSA production represents a useful, non-invasive tool for risk stratification and prediction of graft outcome in kidney transplantation.

Post-transplant donor-specific antibody production and graft outcome in kidney transplantation: results of sixteen-year monitoring by flow cytometry.

Our data show that monitoring by sensitive flow cytometric techniques of the de novo production of anti-HLA antibodies in patients receiving kidney transplantation is a useful and noninvasive tool to identify the onset of an immune response towards the graft before any clinical manifestation of antibody-mediated graft injury. Consequently prospective posttransplant monitoring of anti-HLA donor-directed antibodies may offer the chance to realize an effective clinical intervention in order to prevent graft dysfunction and to prolong graft survival. The long follow-up period of the study allowed us to demonstrate a very low graft survival rate in patients who developed donor-specific HLA antibodies in comparison with patients who did not have antibodies, thus confirming the "humoral theory of transplantation". The posttransplant production of anti-HLA antibodies can predict not only graft failure but also chronic dysfunction of the graft. Moreover, our findings suggest that graft survival is influenced by the epitope- and locus-specificity of anti-HLA donor-directed antibodies. The interval between antibody appearance and loss of graft function was short in some patients but reached several years in others. Moreover, some patients showed consistent production of antibodies for many years and an uneventful clinical status. These findings suggest a mechanism of graft "accommodation" or the production of "harmless" antibodies. Immunosuppressive drug combinations able to inhibit T and B cell activation are useful tools to prevent the humoral immune response against graft and consequently to prolong graft survival.

Chimerism in a child with severe combined immunodeficiency: a case report.

Severe combined immunodeficiency (SCID) represents a group of rare, sometimes fatal, congenital disorders in which there is a combined absence of T-lymphocyte and B-lymphocyte function. Children with SCID die within two years of age, if untreated. The effective treatment for SCID is a hematopoietic stem cell transplantation (HSCT). It has been repeatedly described that in peripheral blood of infants with SCID maternal T cells can be found. Here we report a case of blood chimerism in a one-year-old boy with SCID.

CD30 antigen and multiple sclerosis: CD30, an important costimulatory molecule and marker of a regulatory subpopulation of dendritic cells, is involved in the maintenance of the physiological balance between TH1/TH2 immune responses and tolerance. The role of IFNbeta-1a in the treatment of multiple sclerosis.

OBJECTIVES: The immunological effect of CD30 on dendritic cells (DCs) was examined in a comparative study of patients with relapsing-remitting multiple sclerosis (RRMS). The patients were divided into two groups on the basis of interferon (IFN)beta-1a treatment: IFNbeta-1a-treated patients and untreated patients. We have already shown that CD30 is a marker of cells involved in the regulation of the balance between TH1 and TH2 immune responses and so the aim of this study was to confirm this role in DCs and, consequently, to clarify the immunopathological mechanisms of MS and the causes of immunosuppressive drug failure. METHODS: We studied network interactions between soluble (s) CD30 and TH1/TH2 cytokines in the supernatants of CD14+-derived immature DC (IDC) and DC cultures from treated and untreated patients. Network interactions between the sCD30 and cytokines in IDC and DC supernatants were also evaluated in relation to TH1/TH2 cytokine serum levels. RESULTS: Our overall results show that CD30 is expressed on IDCs and DCs, indicating an immunological role in resting and activated physiological conditions. This role would appear to be the regulation of the resting and activated physiological balance between the TH1/TH2 immune functions as abnormal increases in sCD30 levels result in impaired regulation. Further studies are undoubtedly required to clarify this situation. IFNbeta-1a treatment was found to determine a fall in sCD30 levels, leading to the restoration of the normal functional selection of IDCs from progenitor cells and the regulation of the TH1/TH2 network balance. However, IFNbeta-1a treatment may also be responsible for the in vivo suppression of CD30-mediated TH1-DC functions in immune activation. TH1-DC functions are involved in the induction of T-regulatory cells for the physiological deletion of self-aggressive cells. CONCLUSION: We conclude that CD30 is an important costimulatory molecule and marker of a regulatory subpopulation of DCs which induces and modulates immune cells involved in the maintenance of the physiological balance between TH1/TH2 immune responses and tolerance. Elucidating the mechanisms restoring DC and T-regulatory cell function could lead to more effective therapy and strategies for the prevention and treatment of immunopathological conditions such as autoimmunity, transplant rejection, allergy and tumors.

Immunological study of IFNbeta-1a-treated and untreated multiple sclerosis patients: clarifying IFNbeta mechanisms and establishing specific dendritic cell immunotherapy.

OBJECTIVES: A comparative immunological evaluation of multiple sclerosis (MS) patients receiving IFNbeta treatment and patients who are not receiving treatment may help clarify IFNbeta neurological mechanisms and lead the way to an effective dendritic cell (DC) immunotherapy. This type of study helps clarify the pathological function of T cells and DCs within the TH1/TH2/TH3 network as well as the specific interactions between TH1/TH2/TH3 cytokines implicated in MS pathological mechanisms and determine the best way of reestablishing the TH1/TH2/TH3 network equilibrium. METHODS: We studied network interactions between TH1/TH2/TH3 cytokine levels in serum and supernatants of whole blood and CD14+ monocyte-derived DCs in the remission phase of the disease and in correlation to the Expanded Disability Status Scale (EDSS). RESULTS: We found that TH1 dysregulation results in a disruption of the maturation and activation of dendritic and T cells, and a lack of T-regulating cells for the induction of self-tolerance; IFNbeta mechanisms restore regulation by reestablishing the network balance but fail to resolve the disease completely due to in vivo IL12p70 network interactions leading to the deletion of self-aggressive cells. CONCLUSIONS: Our results indicate that a specific DC immunotherapy could cure rather than treat MS. The best point to reestablish the normal physiological cycle is at the immature DC stage which can be done in vitro with treated peripheral blood CD14+ cells and used in vivo to stimulate the expansion of specific regulatory T cells.

Correlation between ERG changes and FGF2 mRNA Up-regulation in patients with choroidal melanoma.

To study electroretinographic (ERG) response to light flashes in patients with choroidal melanoma and to define possible factors involved in the modification of both a- and b-wave.ISCEV standard flash-ERG was recorded from both affected and control eyes on 24 patients before surgical operation (local excision or enucleation). The choroidal melanomatous mass ranged from 33 to 2880mm(3). Tissues from both melanomatous retina-choroid complex and areas far from the melanoma (unaffected) were taken from 13 enucleated eyes to measure the level of FGF2 mRNA, utilizing the technique of semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Tissues from 10 normal eyes were used as control. The majority of patients showed a marked a- and b-wave attenuation in the affected eye with respect to the fellow eye. In 10 retinal specimens, the expression of FGF2 mRNA showed an increase in retinal regions far from the melanoma compared to control eyes. Many patients present an increase in the expression of FGF2 mRNA in the unaffected part of the retina and a clear attenuation in both a- and b-ERG components. The size of melanoma does not predict the amount of reduction in the ERG response, at least for sizes less than 1000mm(3). We suggest that the melanoma triggers a process leading to an up-regulation of FGF2 in the human eye and this up-regulation might be responsible for the ERG attenuation.