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BACKGROUND: The Luminex Single-Antigen Beads (LSA) assay allows an accurate detection and characterization of preexisting donor-specific antibodies (DSA) in kidney transplant candidates. But the ability of LSA to detect quite low levels of antibodies makes it hard to correctly predict crossmatch results in donor selection. In this study we retrospectively analyzed the accuracy of our virtual crossmatch (v-XM) protocol, which was used for selection of potential kidney transplant recipients, in predicting the results of actual crossmatch (a-XM) in cadaver-donor renal transplantation. We also investigated correlation between negative a-XM results and strength/specificity of preformed DSA. METHODS: The correlation between negative v-XMs and a-XMs performed in 2007-2012 at the Regional Transplant Center of the Lazio Region, Italy, was analyzed. In carrying out v-XM, the donor HLA molecules against which patients showed LSA-detected DSA with normalized mean fluorescence intensity (MFI)>=5,000 were considered to be "unacceptable DSA," and LSA-DSA showing MFI

Since 2013, the regional network of transplantation centers "LAZIO TRANSPLANT" have adopted a new, mixed system for the allocation of liver grafts.The organs from donors aged 65 are assigned to patients with higher Model for End-stage Liver Disease (MELD) scores on a common regional waiting list, whereas those from donors aged65 are allocated to patients with higher MELD scores on a specific local waiting list (LWL) at each center, on a rotational basis.The new mixed allocation model grants a more rational allocation of the "standard" organs to the patients with the actual worst MELD score in the entire region, avoiding the possibility that a patient in relatively better clinical condition might be transplanted before a more severely ill patient on another center's waiting list. Nonstandard organs, presenting slightly increased transplant risks, are still allocated on a rotational basis among the different transplant centers, ensuring them the possibility to select, on the basis of a global clinical risk evaluation, those patients in their LWL whose MELD score would not grant any possibility to compete for the "standard" organ allocation.The application of the new model had no negative impact on the overall number of transplants performed or on the global list-satisfaction percentages, but has slightly improved the cumulative mortality of the patients in the waiting list, granting to the clinically worst patients a prompt graft allocation, independent of the local center belonging.

Aberrant redox regulation occurs in immune and neurological pathologies, hence targeting the pathways involved in the regulation of the redox system could provide further insights into these diseases and open up new avenues for therapy. Soluble (s) CD30 is of key clinical importance in this respect, as its levels reflect the functionality of the CD30 receptor (CD30R), the specific lymphocyte receptor for thiol disulfide/oxidoreductase thioredoxin 1 (Trx1) which is known to regulate important immune and neurological processes. Increased levels of sCD30 appear to be a common element of oxidative stress, immunological alterations and neurological deficit, therefore these increases could be used as a clinical biomarker and target for therapy. We targeted sCD30 in our study of dendritic cell (DC) regulation of the T helper (Th) cell network in multiple sclerosis (MS) patients, as abnormalities in T regulatory (Treg)/Th1/Th17 pathways contribute to the pathogenesis of this immunological/neurological disease. DC profiles in Treg/Th1/Th2/Th17-types of cytokine production in culture supernatants were used as they determine the type of Th differentiation. Our results show that sCD30 levels increase significantly in MS patients, reflecting the disruption in the regulation of the Treg/Th1/Th17 cell network. A fall in the level of soluble CD30, induced by IFNβ1a therapy, opposed the increase of neurological deficit through increasing IL10 and TGFβ levels, thus re-establishing network homeostasis but only when this was accompanied by an increase in IL12p70 levels. Since IL12p70 cytokine production is regulated by Trx1, our results indicate that redox system alterations may be the cause of IFNβ1a therapeutic inefficacy. We conclude that an increase in the level of IL10, TGFβ and IL12p70 and a fall in the level of sCD30 represent a means of evaluating the clinical risk/benefit of IFNβ1a treatment.

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.

We describe an additional HLA-Cw*02 variant, HLA-Cw*0208, which has been identified in a renal transplant recipient of Caucasian origin (Italy). After performing preliminary serological typing, we analyzed exons 2 and 3 of the HLA-C locus polymorphism by cloning the amplified DNA and using a sequence-based typing method. The new allele differs from Cw*020202 by one nucleotide substitution at nucleotide 61 (G-->A) of exon 2, which translates to a difference of one amino acid at residue 21 (His-->Arg) of the HLA-C heavy chain. We propose that Cw*0208 was generated by a random point mutation in codon 21 from the Cw*020202 allele, or through gene conversion of Cw*020202 with another allele, probably the Cw*1205 and Cw*1602 alleles.

Evaluation of outcomes is a major step in quality assessment of any health process. In the transplant field, the evaluation of outcome is extremely important for both patients' growing demand for health and for the joint commitment the transplant process requires. In this study, the outcome of 12,647 transplants, carried out between 1995 and 2000 were analysed. Graft survival at 5 years was 79% for kidney, 67% for liver, 72% for heart and 38% for lung. Patient survival was 92% for kidney, 76% for liver, 72% for heart and 38% for lung. In comparison to other international case records [Collaborative Transplant Study (CTS) and The United Network for Organ Sharing (UNOS)], results are similar or even better for all transplant programmes. As a whole, survival after solid organ transplant in Italy ranks among the best for both donations and transplantation. The quality of transplants carried out is above European standards. Nevertheless, the growing health needs of patients require improvement in both the procurement process and in the use of available organs.

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.

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 2880 mm 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 1000 mm 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.

This report presents a novel allele, HLA-B*4427, which was identified in a bone marrow donor of Caucasian origin, and a confirmatory sequence (B*44022). Sequence analysis revealed the new allele differs from B*44021 by a single nucleotide exchange at position 668 (C-->T), which is located in exon 4. At the protein level, it is the only B*44 variant to produce an Ala in place of a Val at codon 199. Its structure suggests that it may have originated from a point mutation in B*44021 or by gene conversion with a variety of HLA-B alleles. Cloning and sequencing of the allele B*44022 revealed a sequence identical to B*44021 and B*44 exon 4, with the codon GTC (Val) in position 199.

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.

BACKGROUND Improvements in immunosuppressive therapy have greatly reduced acute rejection (ARj) episodes, ensuring better short-term graft outcome, but have not modified long-term survival in renal transplantation. It is now well accepted that chronic rejection (CRj) can be determined by both immune and/or nonimmune mechanisms. The aim of this study was to evaluate the importance of the posttransplant humoral immune response towards mismatched HLA graft antigens in CRj occurrence and graft outcome. METHODS Serum samples from 120 nonpresensitized renal transplant recipients were prospectively screened for 1 year after surgery by means of flow cytometry cross-match (FCXM) and FlowPRA beads (microbeads coated with purified HLA class I and class II antigens) assays. All transplants were followed-up for 2 years or until graft removal. RESULTS FCXM monitoring identified donor-specific antibodies (DS-Abs) in 29 (24.2%) of 120 transplanted patients. Correlation with clinical data highlighted a higher incidence of ARj in DS-Abs-positive patients compared to negative patients (62% vs. 13%, P

Cytokine regulation of lymphocyte survival may play an important role in the control of the cell cycle during the immune response both in health and disease. Expression of the Bcl2 gene promotes cell survival by countering apoptosis stimuli. The p53 protein has been implicated in the control of the cell cycle, in the synthesis and repair of DNA and in programmed cell death. TH1 and TH2 cytokines exert a mutual cross-regulation on the precursors of TH1- or TH2-type effector cells which are important mediators in directing the immune system towards the appropriate response. TH1 and TH2 cytokines have also been implicated in the modulation of the expression of cell cycle regulator genes. Therefore, the study of the relationships between TH1 and TH2 cytokines and Bcl2 and p53 molecules in healthy subjects could lead to a better understanding of the physiological regulation of the immune response and identify markers for prognostic and diagnostic indices and biotherapeutic treatment. We determined the serum levels of cytokines (IL2, IFN gamma, IL4, IL10, IL5, IL6, IL1 beta, TNF alpha, IL8), soluble receptors (sIL2R, sIL6R), Bcl2-protein and p53-antibody in a group of healthy subjects. Multivariate statistical analyses were used to study the cytokine network relationships with Bcl2-protein and p53-antibody, as they allow a simultaneous evaluation of all variables which reflects the physiological situation. Our overall results suggest that relationships exist between TH1 and TH2 cytokines and the Bcl2-protein and p53-antibody in physiological conditions. This information could now be used in experimental studies to create diagnostic and prognostic indices for the monitoring of health and disease.

In order to study the role of interleukin-1beta (IL-1beta) in homeostasis, hypoxia and recovery of neuronal cells, we studied the expression and release of tumor necrosis factor-alpha (TNF-alpha) and nerve growth factor (NGF), in relation to the presence or absence of this cytokine in culture medium. Moreover, we evaluated cell mortality in the same conditions. For this aim, we used untreated and IL-1beta pre-immunoneutralized hippocampal neuronal cultures exposed to mild hypoxic stress and left to reoxygenate. Semiquantitative reverse-transciptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) determined gene expression and protein levels. Mild hypoxic stress provokes a decrease in both the expression and release of TNF-alpha and NGF. IL-1beta neutralization results in an inversion of this pattern since treated hypoxic cultures exhibited an increase of both expression and release of NGF. In pretreated hypoxic cells the increased expression of TNF-alpha was not followed by a rise in release. Reoxygenation reversed the observed effects in both cultures and the levels of cytokine expression and release were approaching control values. Our data show that in physiological conditions IL-1beta may have a neuroprotective action through positive modulation of NGF. Contrary to that, in presence of insult, IL-1beta may have an opposite role, since neutralization provoked an increase of expression and release of NGF. In addition, we demonstrated that neuronal cells are biochemically capable, not only of maintaining and recovering the homeostasis, but also of activating the appropriate response to insult. IL-1beta may have a pivotal role in this mechanism through the modulation of NGF and to a lesser degree of TNF-alpha.

Donor-recipient HLA matching was retrospectively evaluated in 111 cadaveric renal transplants using Takemoto's ten-residue model in which HLA class I antigens are clustered by crossreactive group (CREGs) on the basis of amino acid sequence homology and the sharing of a particular public epitope. The grade and type of HLA residue mismatching were correlated to posttransplant, class I donor-specific antibody production (monitored by flow cytometry crossmatch), rejection occurrence and clinical outcome during the 1st year posttransplant. In 52 patients with 0 mismatchings (MMs) we observed a low incidence of rejection (11.1 %) and antibody production (11.1 %) for 0 CREG MM grade, while 1 MM was enough to increase immune response against graft (rejection 35 %; antibodies 30 %). Moreover, a significant correlation was observed between Q144, E163, Q62 and L82/R82 epitopes and the incidence of acute rejection and antibody production (“immunogenic” residues) in patients grouped for a single residue mismatch.

This report describes the unknown exon 4 sequence of the rare human leukocyte antigen-Cw*0716 allele, identified in a Caucasian renal transplant recipient from Italy. This sequence is identical to the Cw*070101 allele, and this result allowed us to confirm the hypothesis of the generation of Cw*0716 allele by an interallelic recombination event between Cw*0701/0706/0718 and Cw*020202 allele.

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.

B*3812 is a novel allele identified in our laboratory during the typing procedure for hematopoietic cell transplantation purpose. The name B*3812 has been officially assigned by the WHO Nomenclature Committee in November 2005.

The present study has been designed to investigate whether intrastriatal implantation of mesencephalic dopamine (DA)-synthetizing neurons into the striatum (ST) of rats whose substantia nigra (SN) was previously destroyed by 6-hydroxydopamine (6-OHDA) restores the pattern of corticostriatal transmission from the medial prelimbic and sensorimotor cortices. In 6-month-old normal animals electrical stimulation of these two functionally unrelated cortices evoked a short latency and brief excitation in 81.6% of neurons recorded in the dorsolateral ST. This percentage decreased significantly (70.6%) in age-matched animals whose dopaminergic nigrostriatal pathway was unilaterally destroyed by 6-OHDA 3 months before recording. However a significant increase in neurons (36.9%) which could be simultaneously activated from the two cortices in comparison to intact rats was noted. In addition the lesion caused a significant decrease in the threshold current required to evoke activation of striatal neurons from the sensorimotor cortex. The increase in the number of striatal neurons responding simultaneously to cortical stimulations demonstrates that destruction of the dopaminergic nigrostriatal pathway causes a loss of the focusing action of DA on corticostriatal transmission. Transplantation of embryonic mesencephalic neurons appears to reestablish this action since the number of convergent responses was significantly decreased in grafted animals (23.5%) in comparison to denervated (36.9%) and sham-grafted (35.1%) animals. Furthermore, the grafts showed a trend to increase current intensities required to evoke activation of striatal cells from both cortices. The action of grafted mesencephalic neurons over prelimbic and sensorimotor cortical inputs to the dorsal ST could be involved in recovery of grafted animals in the correct execution of complex sensorimotor tasks requiring integration of different cortical signals within the ST.

Neuronal mortality, interleukin-1Β (IL-1Β) and tumor necrosis factor-Α (TNFΑ) release were measured in hypoxic hippocampal neuronal cultures. Release of IL1Β and TNFΑ was

These studies have examined the extent to which intrastriatal grafts of embryonic mesencephalic neurons induce recovery of normal discharge patterns in striatal neurons of rats after a unilateral 6-hydroxydopamine (6-OHDA) lesion of the nigrostriatal dopamine (DA) pathway. Lesioned rats were tested for rotational behavior induced by amphetamine and apomorphine. Animals which responded positively to these tests received two suspensions of mesencephalic embryonic neurons into the dorsal striatum (ST) ipsilateral to the denervated side. Sham-grafted rats received the suspension medium only. The vitality of the graft was assessed by the disappearance or reversion of rotational movements induced by amphetamine. Extracellular recordings of neurons located throughout the ST were carried out 3 months after grafting, when the animals reached the age of 6 months. The 6-OHDA-induced nigral lesion caused a net increase both in the number of striatal neurons spontaneously active and in their discharging rates. The signs of increased neuronal activity were also present in sham-grafted animals. The grafting of embryonal cells strongly reduced the number of active neurons and decreased significantly their discharging rate. The effects of the intrastriatal graft appeared to be present within a radius of 1.5-2 mm from the core of the grafted area. The presence of tyrosine-hydroxylase-immunopositive neurons innervating the host ST confirmed the viability of the grafts at the time of electrophysiological recording. The results show that besides compensating motor asymmetries caused by DA denervation, intrastriatally grafted dopaminergic neurons are able to only partially restore the electrophysiological action of DA in discrete striatal domains.

Recent theories have established that, during an ongoing immune response, the lymphokines produced by TH1 and TH2 subsets of CD4+ T cells are critical to the effectiveness of that response. In vivo and in vitro studies have demonstrated that the type of environmental cytokines plays a determinant role in directing the development of naive T cells into TH1 or TH2 effector cells. Disregulated expansion of one or other subset may contribute to the development of certain diseases. To establish whether a similar situation might exist in the cells of the peripheral blood (PBMC) of colorectal cancer patients, we have performed immunological studies on a group of patients and a group of healthy subjects. We examined the interleukin-2 (IL-2), interferon gamma (IFNgamma), IL-4, IL-6 and tumour necrosis factor alpha levels in serum; the production of IL-4 and IL-2, with and without activating agents, by PBMC, tumour-draining lymph node lymphocytes and tumour cells; and the proliferative response of PBMC to IL-2, IL-4 and anti-CD3 monoclonal antibody (anti-CD3), which were variously combined. The data of the present study lead us to hypothesize that, because of suppressive effects probably due to environmental IL-4, in the peripheral blood of patients there seems to be a disregulation in the functionality of TH1 and TH2 subsets of CD4+ T cells, with an expansion in TH2 and a malfunction in TH1 cells. Moreover it seems that this disregulation increases with as the disease progresses through the stages, suggesting that it can be directly implicated in the mechanisms that allow the tumour to locate and progress in the host.

Aim: In kidney transplant candidates an increase of the rare HLA alleles due to immigration flow growth was observed. The high polymorphism of HLA alleles should make difficult the finding a suitable donor, especially in sensitized patients. In fact, humoral immune response often determines the production of a broad antibodies pattern due to the recognition of mismatched HLA epitopes. Methods: We analyzed the presence of rare HLA alleles in 934 renal transplant candidates, routinely typed by SSP/-rSSO method and, on the basis of HLA antibody identification, the typing was enlarged to pertinent HLA loci. Rare alleles were confirmed by high resolution SSP method. The allele frequencies (af) were assessed by direct count and the potential immunogenic epitopes were assessed comparing amino acid sequences of these alleles with the corresponding alleles by an online database. Results: A total of 20 rare alleles (2.1%) was found and some of these are give below: B/14:06:01 (af = 1.96%, Caucasian patient), differs from other B/14 alleles by Tryptophan?Arginine substitution at position 97; B/15:38 (af = 1.00%, Asian patient), differs from other B/15 alleles by Histidine?Tyrosine substitution at position 171; B/18:18, (af = 0.58%, Caucasian patient), differs from other B/18 alleles by Serine?Tyrosine substitutions at position 99; B/51:07 (af = 0.58%, Caucasian patient), differs from other B/51 alleles by Serine? Phenylalanine substitution at position 67; DRB1/14:16 (af = 0.93%, Caucasian patient) differs from other DRB1/14 alleles by Leucine?Isoleucine, Arginine?Aspartic acid, Arginine?Glutamic acid, Glutamic acid?Alanine substitutions at positions 67, 70, 71, 74; DQB1/03:05 (af = 0.88%, Caucasian patient), differs from other DQB1/03 alleles by Leucine?Glycine substitution at position 26. Conclusions: The presence of rare HLA alleles suggests a new policy of HLA typing providing amino acid sequence information and the application of an epitope-based HLA-matching to improve clinical course of kidney transplantation.

Aim: De novo production of donor-specific HLA antibodies (DSA) represents the major risk factor of graft failure in kidney transplantation. However, some patients show persistent presence of circulating DSA without occurrence of graft dysfunction/loss. Newer solid phase assay Luminex Single Antigen (LSA) beads, is highly sensitive respect to complement-dependent citotoxicity assay but less predictive of transplant outcome because of detection of both complement-fixing and less clinically relevant no complement-fixing HLA antibodies. Methods: Using Class I and II C1q-LSA assay (One Lambda,CA), that identifies antibodies able to fix C1q, we investigate the clinical relevance of de novo HLA-DSA in 40 kidney transplanted patients. As for transplant outcome, 22 patients suffered graft failure (within 10 ± 1 months from DSA appearance) and 18 had good graft function during all the follow up (mean 54 ± 34 months from DSA appearance). Results: Twenty-three patients showed production of C1q-positive DSA while 17 produced C1q-negative DSA. Correlating graft outcome and capability of DSA to fix C1q, graft failure occurred in 20/23 C1q-positive DSA patients; only 2/17 C1q-negative DSA patients suffered graft failure (87% vs.12%, P < 0.0001; RR = 7.39; Sensitivity = 0.91; Specificity = 0.83; PPV = 0.87; NPV = 0.88). It is to underlay that both C1q-positive and C1q-negative DSA were mainly specific for DQ donor mismatched molecules (74% vs. 53%); the 53% of anti-DQ C1q-positive DSA were specific for DQ1 molecules while the 75% of anti-DQ C1q-negative DSA were specific for DQ2 molecules. Conclusions: C1q-LSA assay showed the capability to identify the subset of IgG-LSA DSA strongly associated to antibody-mediated rejection and graft loss in kidney transplantation; moreover, its ability in distinguishing less harmful no complement-fixing DSA from clinically relevant C1q-fixing DSA, allows to identify patients that need specific immunosuppressive strategy to prolong graft survival.

Soluble interleukin-2 receptor (sIL-2R) levels have been found to be elevated in several clinical conditions, including disseminated solid neoplasms, whereas they are generally within the normal range in patients with locally limited neoplastic disease. The aim of the present study was to examine this in our colon cancer patients, and to assess if this situation can affect the in vitro activation of peripheral blood mononuclear cells (PBMC), examining the proliferative response to IL-2 and anti-CD3 monoclonal antibody, the IL-2 serum levels and the PBMC phenotype. The results show that sIL-2R levels were significantly correlated with the stage of the disease, showing an increase from stage I to stage IV; moreover, it is worth noting that the proliferative response to IL-2 plus anti-CD3 is significantly higher than to IL-2 alone in stage IV, without significant alteration in the numerical presence of T and natural killer cells. So it seems that in the peripheral blood of patients, connected with the disease progression, are present cellular populations showing a different response to activation, and that T cells acquire a better response condition than NK. Thus, since the T cellular population includes the tumour-specific cytotoxic precursor cells, this should be helpful for its tumour regressive activity, but it is conceivable that this population cannot perform its functions, owing to a deficiency in responsiveness of the specific ThCD4+ subpopulation.

The aim of this study was to provide genetic and anthropological information on the Chaouya (CH), an Arabic-speaking population living in West Morocco, Atlantic coast (Settat). In 98 unrelated healthy CH volunteers, we first investigated the human leukocyte antigen (HLA) class I and II allele polymorphisms using a sequence-based typing method and examined haplotypes and relatedness of this group to other African and Mediterranean populations. The study showed the close relatedness with Tunisian population and other North Africans, together with a strong influence of various immigrations, mainly Spaniards, French, and Portuguese, as expected. Nevertheless, analysis of class II allele frequencies (afs) showed that Oromo and Amhara Ethiopian groups cluster together with the Berbers and other North Africans, confirming the relationship between these populations (Afro-Asiatic linguistic group, Hamites). South and sub-Saharan Africans cluster separately at a great distance from CH, except the sub-Saharan Bantu population from Congo Kinshasa, which shows a relatively close genetic relationship ascribable to the effect of a diversifying selection. On the other hand, considering HLA class I afs analyses, it was noteworthy that CH grouped together with sub-Saharans, showing a close genetic distance mainly with Ugandas and Kenians Luo.

Acknowledgments: This research was supported in part by funding from the C.N.R., P.F. “Biotecnologie”. We wish to acknowledge and thank Dr. Maria Teresa Vicentini, Dr. Lorena Pompucci and Dr. Anna Aureli for their support with HLA typing. Abstract: This communication describes a new DRB1*11 allele identified in a familial group of Caucasian individuals from central Italy. The new sequence has been officially named DRB1*11272 by the World Health Organization (WHO) Nomenclature Committee (February 2000). It encodes an HLA antigen serologically recognized as DR11. The sequence variation of this new allele was localized to codon 77 of exon 2. It differs at position 230 from DRB1*11011 allele (A replacing C), and at position 231 from DRB1*1127 (C replacing T). At the amino acid level, the DRB1*11272 mutation is silent with respect to the DRB*1127 phenotype, coding for a synonymous asparagine.

In cancer research, as Jarnicki et al. (2006) and Benzoni et al. (2007) have shown, surgery continues to be the main treatment option though irradiation and chemotherapy have become increasingly important and may, in certain cases, improve the cure rate produced by surgery. The need for accurate staging, however, prior to any treatment planning has become increasingly important in a wide variety of malignancies (Vlastos and Verkooijen 2007; Warburton et al. 2007). The detection of widespread metastatic disease in patients and the need for accurate staging before therapy has been long recognized (Skeel 1992), and there is a strong case for restaging cancer after a number of cycles of chemotherapy to determine if continued chemotherapy is required. Staging during an operative procedure is also vitally important to spare the patient the possible morbidity and mortality associated with hazardous procedures. No single staging system is universally employed for all cancers but one of the most commonly used is the pTNM classification system, devised by the American Joint Committee on Cancer et al. (1992), and based on the examination of a surgically resected specimen. This classification takes into consideration the size of the primary tumour (T), the presence and extent of regional node metastases (N), and the presence of distant metastases (M). However it is an invasive method of classification as it is based on the examination of a surgically resected specimen. Many researchers have found that tumor establishment and progression are generally allowed through a malfunction of the immune response (Jarnicki et al. 2006; Berghella et al. 2006; Contasta et al. 2006; Pellegrini et al. 2006). Hence, it is our opinion that a noninvasive method of identifying disease stage could lie with the study of immunological blood parameters.

Aim Post-transplant development of donor-specific antibodies (DSA) had been associated with adverse kidney transplant outcome. Methods In 466 kidney transplanted patients we analyzed the clinical impact of de novo HLA-DSA by Luminex-Single Antigen Beads.

HLA-A*9250 allele was identified by SBT in a Caucasian bone marrow donor. It differs from the closest A*020101 by only one nucleotide (A -> G) at position 124 in exon 2 (Arg to Gly at codon 18); this is an uncommon variation at a highly conserved nucleotide position, located on the loop between S1-S2 beta-sheets in alpha 1 domain.

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.

This study investigated the impact of specific cytokine genotypes on the incidence of acute rejection episodes (ARE), chronic graft dysfunction (CGD), and anti-HLA donor-specific antibody (DS-Ab) production in 86 renal transplant recipients and 70 cadaveric donors. A PCR-SSP method was performed for the analysis of polymorphisms in TNF-alpha, IL-6, TGF-beta, IL-10, and IFN-gamma cytokines. DS-Ab monitoring of sera was performed using a FCXM analysis. Observed cytokine frequencies for patients and donors were not significantly different from the expected frequencies under Hardy-Weinberg equilibrium conditions. The evaluation in recipients revealed a higher frequency of DS-Ab-positive patients among the TNF-alpha high (50.0% vs 25.7%), and for the IL-10 cytokine a greater incidence of ARE-positive patients (35.8% vs 18.2%) with the high + intermediate, compared with the low genotype. The combined effect of these 2 genotypes predisposed to DS-Abs (71.4% vs 25.3%; P = 0.02; odds ratio [OR] = 7.37). As for the TGF-beta1 cytokine, we observed a higher number of CGD-positive patients among high compared with intermediate producers (14.3% vs 0%; P = .050). The analysis of donors revealed a significantly lower incidence of ARE-positive patients among recipients whose donors were carriers of the high IL-6 G/G-genotype compared with the G/C+C/C-genotypes (16.7% vs 41.2%; P = .03), suggesting a protective effect of the G/G genotype on ARE and a predisposing role of donor (-174)allele C. In addition, we noted an association between the IFN-gamma low A/A-genotype and a higher incidence of ARE (42.1% vs 0%; P = .002) and DS-Ab production (47.4% vs 12.5%; P = .02) compared with high producers.

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 p2-value = 0.0001 and = 0.003). Moreover, positive associations were observed for HLA-B-18, -B51 (split of -B5) and -B57 (p2-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; p2-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.

The novel human leukocyte antigen (HLA)-Cw*1609 allele was identified by sequence-based typing in a Moroccan Chaouya donor. It differs from the closest Cw*1602 by only one nucleotide (C --> G) at position 244 in exon 2 (Glu to Gln at codon 58 in alpha1 domain).

CD1 is a small family comprising 5 MHC-like genes located on chromosome 1 and encoding glycoproteins termed CD1a, CD1b, CD1c, CD1d and CD1e. They are expressed mainly on the surface of dendritic cells, monocytes and some thymocytes and are specialized in presenting lipid antigens to T lymphocytes. The structure is similar to that of MHC class I molecules with 3 globular domains and the β2-microglobulin. It has been shown that all five human CD1 genes exhibit a limited number of polymorphisms in the alpha1 domain whose effects are still unknown. CD1e results to be the most polymorphic isoform with six CD1e alleles (01, 02 in exon 2 and 03, 04, 05, 06 in ex3) described to date. At this moment, few investigations on the allele frequencies of the CD1 genes have been reported and all additional information improves our knowledge on this new class of antigen-presenting molecules. In order to study possible allelic variations of exon 2 of human CD1a and CD1e genes, we analyzed, by a sensitive technique, the sequence-based typing (SBT), 114 DNA samples from unrelated healthy Italian individuals from the Abruzzo region. Our experimental findings indicate that the allele frequency distribution of both CD1a and CD1e genes is in accordance with that observed in other geographic areas and did not identify any new allele, thus confirming a very low polymorphism.

THE PRESENCE of anti- donor-specific antibodies before transplantation, detected using a complementdependent lymphocytotoxic test (CDC), is an absolute contraindication to renal transplant; moreover, some authors have observed a high incidence of acute rejection (ARj) episodes1-5 and a decreased graft survival6-9 in kidney transplant recipients with a positive flow cytometric crossmatch (FCXM) before transplantation. FCXM is more advantageous than CDC in that it shows a higher sensitivity in the detection of preformed antibodies10 and allows the simultaneous detection of complement-activating and nonactivating alloantibodies, the class of donor specific antibodies (IgG and/or IgM), and the donor target cells (T and/or B lymphocytes). Nevertheless, pretransplant crossmatching can only give an idea of presensitization. It is not able to identify all patients who will experience rejection following transplantation. Although needle core biopsy represents the most effective tool for diagnosing rejection, many efforts have been made to monitor rejection using less invasive procedures. The aim of this study was to demonstrate that among the many approaches used to monitor rejection in renal transplant recipients FCXM routinely performed after transplantation represents a specific, sensitive, and noninvasive method for monitoring donor specific immune responses. For this purpose FCXM was performed in the first 3 months after transplant on 42 patients who had received cadaveric kidney transplant.

This review 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 in the first place.

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.

B*3812 is a novel allele identified in our laboratory during the typing procedure for hematopoietic cell transplantation purpose. The name B*3812 has been officially assigned by the WHO Nomenclature Committee in November 2005.