Interleukin-9 over-expression and T helper 9 polarization in systemic sclerosis patients.

T helper 9 (Th9) cells and interleukin (IL)-9 are involved in the pathogenesis of several autoimmune diseases. The exact role of IL-9 and Th9 cells in patients with systemic sclerosis (SSc) have not yet been studied adequately. IL-9, IL-9R, transcription factor PU.1 (PU.1), IL-4, thymic stromal lymphopoietin (TSLP) and transforming growth factor (TGF)-ß expression were assessed in skin and kidney biopsies of SSc patients and healthy controls (HC) by immunohistochemistry (IHC). The cellular source of IL-9 was also analysed by confocal microscopy analysis. Peripheral IL-9-producing cells were also studied by flow cytometry. The functional relevance of IL-9 increased expression in SSc was also investigated. Our results demonstrated a strong expression of IL-9, IL-9R, IL-4, TSLP and TGF-ß in skin tissues of patients with both limited and diffuse SSc. IL-9 expression was observed mainly in the context of skin infiltrating mononuclear cells and keratinizing squamous epithelium. IL-9 over-expression was also observed in renal biopsies of patients with SSc. IL-9 producing cells in the skin were identified as Th9 cells. Similarly, Th9 cells were expanded and were the major source of IL-9 among SSc peripheral blood mononuclear cells (PBMC), their percentage being correlated directly with the modified Rodnan skin score. Infiltrating mononuclear cells, mast cells and neutrophils expressed IL-9R. In in-vitro studies stimulation with rIL-9 significantly induced NET (neutrophil extracellular traps) release by dying cells (NETosis) in neutrophils, expansion of mast cells and increase of anti-systemic scleroderma 70 (Scl70) production by B cells. Our findings suggest that Th9 cells and IL-9 could be implicated in the pathogenesis of SSc.

Improvement in vaccination knowledge among health students following an integrated extra curricular intervention, an explorative study in the University of Palermo.

INTRODUCTION: Vaccination coverages threaten to decrease because of false beliefs in their unsafety and inefficacy. Therefore formation of future health-care workers on this topic is fundamental to deal with any doubt and to promote active immunization among general population. METHODS: In order to assess health-care students' knowledge about vaccination before an integrated seminar on this topic, and to evaluate their improvement after the educational intervention, an integrated educational intervention was held by a multidisciplinary team. Before and after the seminar, 118 students of medicine and biology schools at Palermo University were asked to answer 10 multiple-choice questions regarding vaccine history, mechanism of action, side effects, composition, use and nowadays issues (hesitancy). Two more questions investigating possible changes on students' attitudes towards vaccination and the usefulness of the formative intervention, were added at the post-test phase of the survey. RESULTS: Eighty-one out of 118 students (68.6%) answered to both pre- and post-test questions. 97.6% and 81.5% of the participating group also completed the two additional questions about their improvement in knowledge (question 11) and attitudes (question 12) towards vaccinations. The post-test results showed a significant improvement for all questions administered, except for number 3 (about a specific immunological content), with an overall percentage of correct answers increasing from 38.8% to 77.6% (p©< 0.001). CONCLUSIONS: The present explorative study put the basis for future studies, stronger in the methodology, and highlights the importance of educating health-care professions students by integrated extra-curricular intervention to be held early in their degree curricula and in order to improve knowledge and attitudes towards vaccinations and to prepare them to promote vaccines among the general population.

Interleukin (IL)-9/IL-9R axis drives γδ T cells activation in psoriatic arthritis patients.

Cytokines such as tumour necrosis factor (TNF)-α, interleukin (IL)-12, interferon (IFN)-γ, IL-23 and, more recently, IL-9, have been implicated in the initiation/maintenance of inflammation in psoriasis and psoriatic arthritis (PsA). In the present study we aimed to characterize the role of γδ T cells in peripheral blood and synovial fluid of PsA patients and to investigate their response to in-vitro stimulation with antigen or cytokines (IL-9 and IL-23). γδ T cells isolated from peripheral blood mononuclear cells and synovial fluid were analysed by flow cytometry to evaluate the phenotype and cytokine production. IL-23R and IL-9R gene expression were also evaluated by reverse transcription-polymerase chain reaction (RT-PCR). Peripheral blood mononuclear cells (PBMC), sorted γδ T cells and γδ cell lines were also stimulated in vitro with isopentenyl pyrophosphate (IPP), recombinant IL-9 or recombinant IL-23. Our results show an expansion of γδ T cells with a predominant effector memory phenotype in peripheral blood and synovium of untreated PsA patients, which reverses significantly after treatment with anti-TNF-α or anti-IL-12/IL-23R monoclonal antibodies (mAbs). Moreover, in PsA patients γδ T cells activation is driven prevalently by IL-9/IL-9R interaction, and not only by IL-23/IL-23R. Together these findings indicate γδ T cells and IL-9 as new players in the pathogenesis of PsA.

Interleukin (IL)-22 receptor 1 is over-expressed in primary Sjogren's syndrome and Sjögren-associated non-Hodgkin lymphomas and is regulated by IL-18.

The aim of this study was to elucidate more clearly the role of interleukin (IL)-18 in modulating the IL-22 pathway in primary Sjögren's syndrome (pSS) patients and in pSS-associated lymphomas. Minor salivary glands (MSGs) from patients with pSS and non-specific chronic sialoadenitis (nSCS), parotid glands biopsies from non-Hodgkin lymphomas (NHL) developed in pSS patients, were evaluated for IL-18, IL-22, IL-22 receptor 1 (IL-22R1), IL-22 binding protein (IL-22BP) and signal transducer and activator of transcription-3 (STAT-3) expression. MSGs IL-22R1-expressing cells were characterized by confocal microscopy and flow cytometry in pSS, nSCS and healthy controls . The effect of recombinant IL-18 and IL-22 on peripheral blood mononuclear cells (PBMCs) from pSS and nSCS was studied by flow cytometry and reverse transcription-polymerase chain reaction (RT-PCR). MSGs of pSS and NHL were characterized by an imbalance between IL-22 and IL-22BP protein expression, with IL-18 and IL-22BP being expressed in a mutually exclusive manner and IL-18 and IL-22R1 being correlated directly. Aberrant expression of IL-22R1, induced by IL-18, was observed only among tissue and circulating myeloid cells of pSS patients and macrophages of NHL tissues of pSS patients, but not nSCS. IL-22R1 expression on PBMC of pSS was functional, as its stimulation with recombinant IL-22 significantly up-regulated the expression of STAT-3, IL-17 and IL-22. An IL-18-dependent aberrant expression of IL-22R1 on cells of haematopoietic origin seems to be a specific immunological signature of patients with pSS and pSS-associated lymphomas.

The in vitro addition of methotrexate and/or methylprednisolone determines peripheral reduction in Th17 and expansion of conventional Treg and of IL-10 producing Th17 lymphocytes in patients with early rheumatoid arthritis.

The aim of our study was to evaluate methotrexate (MTX) and methylprednisolone (MP) effect on peripheral Th17 and Treg subsets in patients with rheumatoid arthritis (RA). We enrolled 15 patients (10 early RA and 5 long-standing disease) with active RA and 10 age-matched healthy donors as controls. Frequencies of Th17 and Treg were quantified using flow cytometry before and after in vitro addition of MTX, MP or both drugs. Our results showed a reduction in the overall Th17 population followed by an increase in Th17 IL-10(+) and Treg, after in vitro treatment of PBMCs with the drugs in patients with early RA. Long-standing disease patients showed a less evident increase in Treg cells and less enhancement of IL-10 Th17 cells. We suggest that the treatment with MTX and MP could ameliorate RA disease activity by normalizing the distribution/imbalance of Th17/Treg and indicate a new regulatory role of IL-17(+) cells in RA patients.

Efficacy and safety of γδT cell-based tumor immunotherapy: a meta-analysis.

Vγ9Vδ2 T cells are important effector cells that may play a role in the anti-tumor immune response. Their capability to exert MHC-nonrestricted lytic activity against different tumor cells in vitro and their detection among tumor infiltrating lymphocytes in a variety of human cancers have supported the development of Vγ9Vδ2 T cell-based immunotherapy in the context of novel treatment against cancer. Accordingly, promising reports from recent clinical trials support the use of V γ9Vδ2 T cells as immunotherapeutic agents, either via adoptive transfer of ex-vivo expanded V γ9Vδ2 T cells or in vivo activation of V γ9Vδ2 T cells with compounds such as phosphoantigens or aminobisphosphonates. In this study we have performed a meta-analysis to assess the objective efficacy and safety of V γ9Vδ2 T cell-based immunotherapy. Database including Pubmed, Web of Science and SCOPUS were investigated to identify relevant studies. Thirteen clinical trials involving patients with advanced or metastatic cancer were selected. In order to estimate the strength of association between V γ9Vδ2 T cell-based immunotherapy and favorable clinical effect or toxicity grade we used event rate (ER) with 95 percent confidence interval (CI). The total effective rate provided significant results (ER = 0.407; P <0.014) while no correlation was found between serious adverse effects and Vγ9Vδ2 T cell-based therapy. This meta-analysis demonstrates that Vγ9Vδ2 T cell-based immunotherapy improves overall survival and, in view of its low toxicity grade, provides a proof of principle for its utilization as adjuvant to conventional therapies for resistant/refractory patients care.

Increased percentages of tumor necrosis factor-alpha+/interferon-gamma+ T [corrected] lymphocytes and calprotectin+/tumor necrosis factor-alpha+ monocytes in patients with acute Kawasaki disease.

In vivo exposure to microorganisms resident in the oral cavity is considered as a possible cause of Kawasaki disease (KD), and some epitopes derived from streptococci display homology with Factor H of Complement. Additionally, calprotectin, a major calcium binding protein released by neutrophils and activated monocytes, could be directly involved in endothelial damage occurring in KD. The aim of our study is to evaluate the percentages of IFN-gamma+ and/or TNF-alpha+ lymphocytes and double positive calprotectin/TNF-alpha monocytes (CD14+) after in vitro stimulation with streptococcal- and/or Factor H-derived peptides, in patients with acute KD. Peripheral Blood Mononuclear Cells (PBMCs) obtained from KD patients and febrile controls were stimulated in vitro with peptides. After culture, cells were collected, stained with fluorochrome-labelled monoclonal antibodies against CD3, CD14, calprotectin, IFN-gamma and TNF-alpha, and cytofluorimetric analyses were performed. Our results showed increased percentages of TNF-alpha+/IFN-gamma+ lymphocytes in KD patients in respect to controls when PBMCs were stimulated with streptococcal or Factor H-derived epitopes. In addition, also calprotectin+/TNF-alpha+ monocytes from KD patients were activated after PBMC in vitro stimulation. These findings lead us to speculate that some peptides, derived from oral streptococci and cross-reactive with the human Factor H of Complement, could induce lymphocyte and monocyte activation potentially involved in the pathogenesis of KD. Our results should be confirmed by further studies enrolling more patients and controls than those analyzed in our study.

Survivin is regulated by interleukin-4 in colon cancer stem cells.

Colorectal cancer has provided an important model to test the stem cell hypothesis of cancer origin, which implies that cancer arises as a result of genetic aberrations in stem cells leading to deregulation of the proliferation/differentiation balance. We and others have demonstrated that, similarly to other solid tumors, colon carcinogenesis and progression are dictated by highly apoptosis-resistant stem-like cells. Our data have suggested that protection from apoptosis is achieved by autocrine production of interleukin-4 (IL-4) through up-regulation of anti-apoptotic mediators. In this study, we extend our analysis to another apoptosis inhibitor widely expressed in tumors, namely survivin (also known as BIRC-5, baculoviral IAP repeat-containing protein 5). We show that this protein, with important roles in cell death counteraction and mitotic progression control, is regulated by the IL-4 pathway in colon rectal cancer stem cells (CR-CSC). Hence, the presence of IL-4 increases survivin levels in our model while cytokine neutralization has opposing effects. Treatment with cytokine neutralizing agent or with leflunomide, Stat6 inhibitor, have similar consequences on survivin localization, increasing its nuclear pool, an observation known to be correlated with a good prognosis in colon cancer patients. These results demonstrate that IL-4, through activation of the STAT-6 signaling pathway, is involved in survivin expression levels as well as its localization. These findings shed more light on the molecular mechanisms involved in IL-4-mediated chemoresistance.

Resistance of natural killer T cell-deficient mice to systemic Shwartzman reaction.

The generalized Shwartzman reaction in mice which had been primed and challenged with lipopolysaccharide (LPS) depends on interleukin (IL)-12-induced interferon (IFN)-gamma production at the priming stage. We examined the involvement in the priming mechanism of the unique population of Valpha14 natural killer T (NKT) cells because they promptly produce IFN-gamma after IL-12 stimulation. We report here that LPS- or IL-12-primed NKT cell genetically deficient mice were found to be resistant to LPS-elicited mortality. This outcome can be attributed to the reduction of IFN-gamma production, because injection of recombinant mouse IFN-gamma, but not injection of IL-12, effectively primed the NKT cell-deficient mice. However, priming with high doses of LPS caused mortality of severe combined immunodeficiency, NKT cell-deficient, and CD1-deficient mice, indicating a major contribution of NKT cells to the Shwartzman reaction elicited by low doses of LPS, whereas at higher doses of LPS NK cells play a prominent role. These results suggest that the numerically small NKT cell population of normal mice apparently plays a mandatory role in the priming stage of the generalized Shwartzman reaction.

In vivo manipulation of Vgamma9Vdelta2 T cells with zoledronate and low-dose interleukin-2 for immunotherapy of advanced breast cancer patients.

The potent anti-tumour activities of gammadelta T cells have prompted the development of protocols in which gammadelta-agonists are administered to cancer patients. Encouraging results from small Phase I trials have fuelled efforts to characterize more clearly the application of this approach to unmet clinical needs such as metastatic carcinoma. To examine this approach in breast cancer, a Phase I trial was conducted in which zoledronate, a Vgamma9Vdelta2 T cell agonist, plus low-dose interleukin (IL)-2 were administered to 10 therapeutically terminal, advanced metastatic breast cancer patients. Treatment was well tolerated and promoted the effector maturation of Vgamma9Vdelta2 T cells in all patients. However, a statistically significant correlation of clinical outcome with peripheral Vgamma9Vdelta2 T cell numbers emerged, as seven patients who failed to sustain Vgamma9Vdelta2 T cells showed progressive clinical deterioration, while three patients who sustained robust peripheral Vgamma9Vdelta2 cell populations showed declining CA15-3 levels and displayed one instance of partial remission and two of stable disease, respectively. In the context of an earlier trial in prostate cancer, these data emphasize the strong linkage of Vgamma9Vdelta2 T cell status to reduced carcinoma progression, and suggest that zoledronate plus low-dose IL-2 offers a novel, safe and feasible approach to enhance this in a subset of treatment-refractory patients with advanced breast cancer.

Analysis of memory and effector CD8+ T cell subsets in chronic graft-versus-host disease.

In humans, the selective depletion of CD8+ cells may prevent GVHD after allogeneic transplantation. These cells can infiltrate and damage target tissues. It is of interest to investigate the phenotypical characteristics and cytotoxic properties of the different CD8+ subsets in cGVHD patients. In a preliminary study we found that patients with cGVHD had a markedly elevated percentage of peripheral blood CCR7-/CD45RA+ cells compared to patients without cGVHD; conversely, the CCR7+/CD45RA+ subsets of CD8+ cells was significantly decreased. In this study, we report in depth on the phenotype of effector T cell subsets in cGVHD patients, as well as their proliferative capability, cytotoxic properties and cellular turnover. We confirm a predominance of effector T cell subsets in cGVHD patients and show that a large fraction of these cells down-regulate CCR7 and re-express CD45RA, thus approaching end-stage differentiation. Moreover CD8+ cells of cGVHD patients have low CD8 coreceptor expression, reduced proliferative potential and a high content of perforin and granzyme A. They also have a lower cell turnover and have more propensity to apoptosis, as demonstrated by BrdU incorporation. Taken together, our findings indicate a perturbation of the balance between naive/memory and effector/CD45RA+ CD8+ T cells, and suggest an involvement of the latter compartment characterized by a high content of cytotoxic equipment, in the pathogenesis of cGVHD.

Γδ T Cell-Based Immunotherapy in Melanoma: State of the Art.

Metastatic melanoma is still associated with a poor prognosis, and there is increasing interest in immunotherapy alone or in combination with other adjuvant therapies. Γδ T lymphocytes play a pivot role in the immune response against cancer, but while γδ-based immunotherapy is already a clinical reality for several solid tumors, data on melanoma are still limited and fragmented. This systematic review presents preclinical and clinical evidence for a role of γδ T lymphocytes in immunotherapeutic strategies for advanced melanoma and discusses research state of the art and future perspectives. Current strategies focus on in vivo stimulation, and ex vivo adoptive therapy and vaccination; results are promising, but further studies are needed to better investigate the interactions in tumoral microenvironment and to improve clinical efficacy of immunotherapeutic protocols.

Plasma granulysin levels and cellular interferon-gamma production correlate with curative host responses in tuberculosis, while plasma interferon-gamma levels correlate with tuberculosis disease activity in adults.

Granulysin is a recently identified cytolytic protein which is expressed by human cytotoxic T-lymphocytes and natural killer (NK)-cells, and has broad antimicrobial and tumoricidal activity. Circulating granulysin levels are associated with T- and NK-cell activity, and may thus reflect protection-associated cellular immune responses. In a case-control study in Indonesia, a highly tuberculosis (TB)-endemic country, we therefore determined plasma granulysin levels in adults with active pulmonary TB before, during, and after TB treatment, both in mild/moderate-TB and advanced-TB patients, and compared these to healthy neighbourhood controls. Adults with active pulmonary TB had significantly lower plasma granulysin levels compared to controls. After 2 months of anti-TB therapy, levels in TB patients had significantly increased, reaching values similar to those in controls. Plasma granulysin levels further increased after completion of TB therapy, being significantly higher than those in controls. Plasma granulysin levels correlated inversely with TB disease activity but not with TB disease severity. In contrast, plasma interferon-gamma (IFN-gamma) levels were significantly higher in active TB cases than in controls, normalised during treatment and correlated with both TB disease activity and TB disease severity. At the cellular level, granulysin and IFN-gamma expression both correlated inversely with disease activity. Interestingly, granulysin was predominantly expressed by IFN-gamma negative T-cells, suggesting that the cellular sources of IFN-gamma and granulysin in TB are partly non-overlapping. The observation that plasma granulysin levels and cellular IFN-gamma production correlate with curative host responses in pulmonary tuberculosis points to a potentially important role of granulysin, next to IFN-gamma, in host defence against M. tuberculosis.

Novel Munc13-4 mutations in children and young adult patients with haemophagocytic lymphohistiocytosis.

Familial haemophagocytic lymphohistiocytosis (FHL) is a genetically heterogeneous disorder characterised by constitutive defects in cellular cytotoxicity resulting in fever, hepatosplenomegaly and cytopenia, and the outcome is fatal unless treated by chemoimmunotherapy followed by haematopoietic stem-cell transplantation. Since 1999, mutations in the perforin gene giving rise to this disease have been identified; however, these account only for 40% of cases. Lack of a genetic marker hampers the diagnosis, suitability for transplantation, selection of familial donors, identification of carriers, genetic counselling and prenatal diagnosis. Mutations in the Munc13-4 gene have recently been described in patients with FHL. We sequenced the Munc13-4 gene in all patients with haemophagocytic lymphohistiocytosis not due to PRF1 mutations. In 15 of the 30 families studied, 12 novel and 4 known Munc13-4 mutations were found, spread throughout the gene. Among novel mutations, 2650C-->T introduced a stop codon; 441del A, 532del C, 3082del C and 3226ins G caused a frameshift, and seven were mis sense mutations. Median age of diagnosis was 4 months, but six patients developed the disease after 5 years of age and one as a young adult of 18 years. Involvement of central nervous system was present in 9 of 15 patients, activity of natural killer cells was markedly reduced or absent in 13 of 13 tested patients. Chemo-immunotherapy was effective in all patients. Munc13-4 mutations were found in 15 of 30 patients with FHL without PRF1 mutations. Because these patients may develop the disease during adolescence or even later, haematologists should include FHL2 and FHL3 in the differential diagnosis of young adults with fever, cytopenia, splenomegaly and hypercytokinaemia.

Distinctive features of tumor-infiltrating γδ T lymphocytes in human colorectal cancer.

γδ T cells usually infiltrate many different types of cancer, but it is unclear whether they inhibit or promote tumor progression. Moreover, properties of tumor-infiltrating γδ T cells and those in the corresponding normal tissue remain largely unknown. Here we have studied features of γδ T cells in colorectal cancer, normal colon tissue and peripheral blood, and correlated their levels with clinicopathologic hallmarks. Flow cytometry and transcriptome analyses showed that the tumor comprised a highly variable rate of TILs (5-90%) and 4% γδ T cells on average, with the majority expressing Vδ1. Most Vδ1 and Vδ2 T cells showed a predominant effector memory phenotype and had reduced production of IFN- Î³ which was likely due to yet unidentified inhibitory molecules present in cancer stem cell secretome. Transcriptome analyses revealed that patients containing abundant γδ T cells had significantly longer 5-year disease free survival rate, suggesting their efficacy in controlling tumor at very early stage.

In vitro effects of aminobisphosphonates on Vgamma9Vdelta2 T cell activation and differentiation.

In this study we have evaluated the in vitro effects of four different aminobisphosphonates, alendronate, risedronate, neridronate and zoledronate, on Vgamma9Vdelta2 T cell activation and differentiation. All tested aminobisphosphonates induce an IL-2-dependent activation and expansion of Vgamma9Vdelta2 T lymphocytes in primary PBMC cultures of healthy donors. Most notably, they also determine a different distribution of Vgamma9Vdelta2 T cell subsets, with decrease of T(naive) and T(CM) cells and increase of T(EM) and T(EMRA) Vgamma9Vdelta2cells, indicating that in vitro treatment with aminobisphosphonates induces Vgamma9Vdelta2 T lymphocytes to differentiate towards an effector/cytotoxic phenotype. Accordingly, Vgamma9Vdelta2 T lymphocytes cultured with aminobisphosphonates and IL-2 showed a major content of IFN-gamma and acquired the ability to kill tumor target cells.

Time course of mycobacterial infection of dendritic cells in the lungs of intranasally infected mice.

SETTING: Dendritic cells (DC) could regulate between the protective and pathogenic immune responses following tuberculous infection. In this paper we investigated if their early infection in the lungs represents a plausible alternative to cross-priming with mycobacterial antigens acquired from infected macrophages. OBJECTIVE: To determine the extent and time course of infection of lung DCs following intranasal inoculation of BALB/c mice with green fluorescent protein (GFP) tagged Bacillus Calmette-Guerin (BCG). RESULTS: A fraction of GFP-BCG infected lung cells were classified as monocytic DCs with the CD11c+IA+33D1+CD8a- phenotype. These cells represented 5-18% of the total GFP+ cells, the bulk of which were macrophages. The infected DCs could be separated by cell size into two fractions with similar cell surface staining properties during the 2-72 h period after infection. An unexpected difference was observed for the time course of infection between DCs and macrophages: DC infection peaked at 48 h followed by decline at 72 h, while the proportion of infected macrophages remained steady during the same period. CONCLUSION: The presented results are direct evidence that monocytic DCs are recruited to the lungs and take up live bacilli within 48 h of intranasal infection with GFP-BCG. This finding is pertinent for the regulation of pulmonary and systemic immune responses and possibly for the dissemination of mycobacterial infection by DCs.

Role of gamma delta T lymphocytes in immune response in humans and mice.

T lymphocytes recognize antigen through the T cell receptor. T cells expressing the gamma delta T cell receptor have been found in many species. Whereas murine alpha beta T cells are concentrated in the lymphoid organs, gamma delta T cells represent only a minor population in the adult thymus and peripheral lymphoid organs (less than 5% of the population). However, murine gamma delta cells predominate in epidermis, in epithelial layers of small intestine, in lung, and in female reproductive organs. In contrast, human gamma delta cells predominate in lymphoid organs. Despite extensive progress in the molecular characterization of the gamma delta T cell receptor and its genes, the physiological role of gamma delta T cells has remained elusive for many years. It is becoming now clear that, in contrast to alpha beta cells that recognize peptide/MHC complexes, gamma delta T cells appear to recognize unprocessed proteic antigens and, in humans, also a class of widely represented nonproteic antigens containing critical phosphate moieties. Similarly, it is now known that gamma delta cells can perform a vast array of immune effector functions and appear to play important roles in antimicrobial immunity as well as in chronic inflammatory reactions.

CD1d expression by hepatocytes is a main restriction element for intrahepatic T-cell recognition.

The liver has specific mechanisms to protect itself from infectious agents and to avoid autoimmunity, indicating an important role of the hepatic tissues in antigen presentation and tolerance induction. Since intrahepatic lymphocytes may contribute to the innate immunity and to the liver pathology, it is of interest to analyze the expression of antigen presenting molecules and of the related T cell recognition in liver, and how these change in relation to different diseases. We analyzed the expression of MHC class I, and of CD1-a, -b, -c, and -d proteins on liver tissues from patients with different hepatic diseases. Moreover, in the same patients we studied the intrahepatic and peripheral NKT cell recognition of alpha-galactosyl ceramide antigen in the context of CD1d. Unlike in other tissues, classical MHC class I molecules were poorly expressed in the hepatic compartment, suggesting that inflamed hepatocytes may trigger weak MHC-restricted T cell responses. Nevertheless, we observed a prevalent expression of HLA class I-like CD1d isoform on the hepatocyte surface, indicating that CD1d is the main restriction element in the liver. In patients with viral hepatitis, the intrahepatic CD1d expression parallels the recruitment of CD56+Valpha24Vbeta11+ NKT cells in the liver which recognize CD1d presenting glycolipids such as alpha-galactosyl ceramide, suggesting that the intrahepatic T cell immunity may focus on glycolipid antigens.

Atrial natriuretic peptide secretion during development of the rat supraoptic nucleus.

Since a relationship between atrial natriuretic peptide and oxytocin was recently demonstrated in the heart (Gutkowska et al., 1997), the aim of this study was to determine whether a relationship between the two peptides is present also in the rat hypothalamus. For this purpose, we measured ANP-ontogeny in the rat hypothalamus immunohistochemically and compared it with oxytocin-ontogeny which we previously studied. The results showed that the ANP-peptide and mRNA-ANP start at the 18th day of the fetal life. Our earlier data for oxytocin in the rat hypothalamus showed that only mRNA-oxytocin appeared the 18th day of foetal life (Farina Lipari et al., 2001); thus, at the 18th day of foetal life, mRNA-ANP, ANP-peptide and mRNA-oxytocin are present. We conclude that in the hypothalamus, differently from that in the heart, ANP might play a role on the synthesis of the oxytocin since ANP and its mRNA appear earlier than oxytocin.