RESUMO
Cytokines act as pleiotropic polypeptides able to regulate inflammatory/immune responses and to provide important signals in physiological and pathological processes. Several cytokines (Th1, Th2, and Th17) seem to be involved in the pathophysiology of Behçet's disease, a chronic immune-mediated disease characterized by oral and genital lesions and ocular inflammation. Its individual susceptibility seems to be modulated by genetic variants in genes codifying these cytokines. Th1 and Th17 seem to be involved in the disease's active phases, and Th2 seems to affect the development or severity of the disease; however, contrasting data are reported. In this study, some genetic variants of the Th1/Th2 cytokine genes were investigated in Sicilian patients and age- and gender-matched controls. Three very significant associations with Behçet's disease were detected, and combined genotypes associated with increased disease risk were identified. Results obtained point to the key role of Th1/Th2 cytokine genetic variants in disease susceptibility.
Assuntos
Síndrome de Behçet/genética , Síndrome de Behçet/imunologia , Interleucinas/genética , Adulto , Síndrome de Behçet/patologia , Feminino , Frequência do Gene , Variação Genética , Genótipo , Humanos , Interleucinas/imunologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polimorfismo de Nucleotídeo Único , Sicília , Adulto JovemRESUMO
Three molecular protocols using qPCR TaqMan probe, SYBR Green, and loop-mediated isothermal amplification (LAMP) methods were set up for the identification of larvae and adults of an African invasive moth, Thaumatotibia leucotreta (Meyrick, 1913) (Lepidoptera: Tortricidae). The DNA extracts from larval and adult samples of T. leucotreta were perfectly amplified with an average Ct value of 19.47 ± 2.63. All assays were demonstrated to be inclusive for T. leucotreta and exclusive for the nontarget species tested; the absence of false positives for nontarget species showed a 100% of diagnostic specificity and diagnostic sensitivity for all assays. With the SYBR Green protocol, the Cq values were only considered for values less than 22 (cutoff value) to prevent false-positive results caused by the late amplification of nonspecific amplicons. The limit of detection (LoD) for the qPCR probe protocol was equal to 0.02 pg/µl while a value equal to 0.128 pg/µl for the qPCR SYBR Green assay and LAMP method were established, respectively. The intrarun variabilities of reproducibility and repeatability in all the assays evaluated as CV%, ranged between 0.21 and 6.14, and between 0.33 and 9.52, respectively; the LAMP values were slightly higher than other assays, indicating a very low interrun variability. In order for an operator to choose the most desirable method, several parameters were considered and discussed. For future development of these assays, it is possible to hypothesize the setup of a diagnostic kit including all the three methods combined, to empower the test reliability and robustness.
Assuntos
Mariposas , Animais , Técnicas de Diagnóstico Molecular , Mariposas/genética , Técnicas de Amplificação de Ácido Nucleico , Patologia Molecular , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Studies aimed at collecting reference parameters for haematochemical analysis in the elderly are scarce and for the oldest old subjects even more rare. In order to establish the reference values for the most common laboratory text in long living individuals, we measured haematochemical parameters in >100 years old subjects and in aged subjects as control. Six hundred and two centenarians accepted to be enrolled in the study. A case history containing the complete anamnesis, clinical examinations, evaluation of the clinical cognitive and functional tests, was prepared for each centenarian. Blood samples from 120>100 years old subjects free of chronic or acute Illness (i.e. Alzheimer's disease, metabolic diseases, cardiovascular disease, stroke, neoplastic and infectious diseases) were analysed. A population of 381 healthy old subjects (age range 65-85 years old), recruited in the same geographic areas and with the same clinical characteristic of the health centenarians, was utilized as control. Significant differences were observed for blood glucose, ALT, cholesterol and platelet levels, reduced in centenarians respect to the old subjects, whereas blood urea nitrogen levels were found significantly increased in centenarians. In conclusion, reference values of the healthy adults can generally been utilized also for the healthy oldest old group, with the notable exception of the above mentioned laboratory parameters that appear to be modified in long living subjects.
Assuntos
Constituição Corporal , Longevidade/fisiologia , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Estudos de Casos e Controles , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Itália , Contagem de Plaquetas , Valores de Referência , População BrancaRESUMO
In healthy individuals, natural and adaptive immune responses are able to control virus entry into the host. In particular, CD8(+)-mediated cytotoxicity, sustained by the intervention of CD4+ cells, represents the major key event leading to virus eradication. On the other hand, viruses are able to evade from host immune response via several mechanisms, and special emphasis will be placed on hepatitis C virus and chronic Epstein-Barr infections also in view of personal data. Virokines, viroreceptors, and serpins greatly contribute to viral immune escape, and, among virokines, interleukin (IL)-10 has been object of intensive studies. Finally, all these products have been used as biopharmaceuticals, and, for instance, viral IL-10, chemokine-binding proteins, and serpins exhibit in animal models immunosuppressive, anti-inflammatory, and antiatherogenic activities. As far as their use in human trials is concernded, many cautions are required in order to avoid deleterious side effects and, in particular, the purity of the product, its route and frequency of administration, as well as the immune status of the patient should be taken into serious account.
Assuntos
Antivirais/farmacologia , Proteínas Virais/farmacologia , Fenômenos Fisiológicos Virais , Vírus/imunologia , HumanosRESUMO
The genetics of the interaction between host and microbes plays an essential role in the survival of the individual and attainment of longevity. The activation of toll-like receptor (TLR)4 plays a key role in natural and clonotypic immune responses. We evaluated whether TLR4 genotype is a component of genetic background protective versus rickettsiosis and whether this background influences longevity. We genotyped for +896A/G TLR4 polymorphism 78 patients affected with Boutonneuse fever, 78 age-matched controls and 78 advanced age individuals from Sicily. The +869G allele, that attenuates receptor signalling, was significantly overrepresented in patients in comparison with age-matched controls. By analyzing data according to gender, this allele was significantly higher in female patients when compared to advanced age women. Pro-inflammatory responses are programmed to resist fatal infections. So, it is not surprising that the genetic background of people that survive to an advanced age may be protective against infections. However, this seems to occur in women but not in men. In a previous study, the +896G TLR4 allele was overrepresented in advanced age men and underrepresented in men affected by myocardial infarction. Thus, previous and present results tend to agree with the suggestion that men and women may follow different trajectories to reach longevity. For men it might be more important to control atherogenesis, whereas for women it might be more important to control infectious diseases.
Assuntos
Febre Botonosa/genética , Febre Botonosa/metabolismo , Polimorfismo Genético/fisiologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Febre Botonosa/epidemiologia , DNA/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Sicília/epidemiologiaRESUMO
BACKGROUND: Coeliac disease is associated with DQ2 and DQ8 alleles, but other genes also confer an additional genetic risk. AIMS: Defining whether the genetic profiles of interleukin-10, tumour necrosis factor alpha and interferon gamma are associated with an increased coeliac disease risk. PATIENTS AND METHODS: The functionally gene polymorphisms of tumour necrosis factor alpha (-308G/A), interferon gamma (+874T/A) and interleukin-10 (-1082G/A) were typed using sequence specific primer-polymerase chain reaction in 110 Sicilian coeliac disease patients and in 220 Sicilian healthy controls. RESULTS: No differences in genotype frequencies of interleukin-10 polymorphisms were found between coeliac disease patients and healthy controls. A significant increase of -308A (p<0.033; OR: 1.72; CI: 1.27-2.33) and of +874T (p: 0.0045; OR: 3.02; CI: 1.47-6.21) allele frequencies, both in hetero- and homozygosis, was observed in coeliac patients in comparison with healthy controls. In addition, simultaneous significant higher percentages of -308A and +874T alleles (p: 0.0066; OR: 2.33; CI: 1.42-3.82) as well as simultaneous significant lower percentages of -308A and +874T alleles (p: 0.003; OR: 0.23; CI: 0.10-0.60) were observed in coeliac patients compared with healthy controls. CONCLUSIONS: Genetically determined higher frequencies of -308A tumour necrosis factor alpha and +874T interferon gamma alleles, both in hetero and in homozygosis and mostly whether simultaneous, may play a role in predisposing to gluten intolerance. Subjects positive for -308A tumour necrosis factor alpha and +874T interferon gamma alleles have an increased risk for coeliac disease.
Assuntos
Doença Celíaca/genética , Interferon gama/genética , Interleucina-10/genética , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Adolescente , Adulto , Estudos de Casos e Controles , Doença Celíaca/epidemiologia , Criança , Pré-Escolar , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Sicília/epidemiologiaRESUMO
BACKGROUND: In Down syndrome there is an increased prevalence of coeliac disease, but the reasons for this association are yet unknown. AIMS: To evaluate a possible correlation between TNFalpha, IFNgamma and IL-10 genotype polymorphisms with the susceptibility to coeliac disease in Down syndrome patients. METHODS: Single nucleotide polymorphisms of TNFalpha (-308G-->A promoter region), IFNgamma (+874T-->A promoter region) and IL-10 (-1082G-->A promoter region) have been studied in 10 Down patients with coeliac disease, in 40 Down patients without coeliac disease and in 220 healthy controls. Clinical features were also studied in coeliac disease-Down syndrome patients. RESULTS: The 10 coeliac disease-Down syndrome patients had a biopsy proven coeliac disease afterward a serological testing positive to antigliadin, antiendomysium and antitransglutaminase antibodies. Intestinal biopsy showed total atrophy in 6/10 and partial villous atrophy in 4/10 of them. All coeliac disease-Down syndrome patients had silent forms of coeliac disease and classical trisomy 21. No significant differences were observed for the IFNgamma and IL-10 polymorphisms in the studied groups. A significant trend for increase of TNFalpha -308A positive frequency was observed in coeliac disease-Down syndrome patients compared to healthy controls (p=0.043). CONCLUSIONS: Single nucleotide polymorphisms of IFNgamma and IL-10 do not play a role in predisposing Down syndrome patients to coeliac disease, while the TNFalpha -308 allele could be an additional genetic risk factor for coeliac disease in trisomy 21.
Assuntos
Doença Celíaca/genética , Síndrome de Down/genética , Interferon gama/genética , Interleucina-10/genética , Fator de Necrose Tumoral alfa/genética , Adolescente , Doença Celíaca/complicações , Criança , Pré-Escolar , Citocinas/genética , Síndrome de Down/complicações , Predisposição Genética para Doença , Humanos , Lactente , Polimorfismo Genético , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Literature data suggest that human longevity may be directly correlated with optimal functioning of the immune system. Therefore, it is likely that one of the genetic determinants of longevity resides in those polymorphisms for the immune system genes that regulate immune responses. Accordingly, studies performed on mice have suggested that the Major Histocompatibility Complex (MHC), known to control a variety of immune functions, is associated with the life span of the strains. In the last 25 years, a fair number of cross-sectional studies that searched for the role of HLA (the human MHC) genes on human longevity by comparing HLA antigen frequencies between groups of young and elderly persons have been published, but conflicting findings have been obtained. In fact, the same HLA antigens are increased in some studies, decreased in others and unchanged in others. On the whole, that could lead us to hypothesize that the observed age-related differences in the frequency of HLA antigens are due to bias. In our opinion, this hypothesis is real for most studies owing to major methodological problems. However, some studies that do not meet these biases have shown an association between longevity and some HLA-DR alleles or HLA-B8,DR3 haplotype, known to be involved in the antigen non-specific control of immune response. Thus, HLA studies in man may be interpreted to support suggestions derived from the studies on congenic mice on MHC effects on longevity. However, in mice the association may be by way of susceptibility to lymphomas whereas, in human beings, the effect on longevity is likely, via infectious disease susceptibility. Longevity is associated with positive or negative selection of alleles (or haplotypes) that respectively confer resistance or susceptibility to disease(s), via peptide presentation or via antigen non-specific control of the immune response.
Assuntos
Longevidade/genética , Longevidade/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Polimorfismo Genético , Envelhecimento/genética , Envelhecimento/imunologia , Animais , Predisposição Genética para Doença , Antígenos HLA/imunologia , Humanos , Imunogenética , Complexo Principal de Histocompatibilidade/genética , CamundongosRESUMO
T cell function is altered in vivo and in vitro in elderly compared with young subjects, and this alteration is believed to contribute to morbidity and mortality in man due to the greater incidence of infection, as well as autoimmunity and cancer in elderly. The majority of T cells express TCRalphabeta whereas TCRgammadelta is expressed on a minority of T cells. Moreover, it is known that gammadelta T lymphocytes display major histocompatibility complex (MHC)- unrestricted cytotoxicity that is reminiscent of natural killer (NK) activity. In view of earlier findings on both T cells and NK cells in the elderly, we hypothesised a different behaviour of gammadelta T lymphocytes from old subjects when compared with gammadelta T lymphocytes obtained from young people. Therefore, to gain further insight into mechanisms of immunosenescence in this little-studied population, we studied immunofluorescence analysis gammadelta T cells from the elderly. Our preliminary results show that the percentage of blood gammadelta T cells in lymphocytes from old subjects is decreased when compared with the young. Interestingly, these cells are more activated in the elderly than in young subjects; expression of CD69, an early activation marker, is increased in gammadelta T lymphocytes from old subjects after three hours of in vitro culture both with and without lipopolysaccharide stimulation. Thus, our findings, which need confirmation, strongly suggest that, in humans, gammadelta T cells are early responders when compared with alphabeta T cells. They may act as 'first aid' cells to replace the described deficit of the specific and aspecific immunity in elderly. In this view, the proinflammatory status, observable in the elderly, renders them ready to be stimulated by exogenous agents.
Assuntos
Envelhecimento/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Feminino , Humanos , Lectinas Tipo C , Masculino , Pessoa de Meia-Idade , Linfócitos T/metabolismoRESUMO
A large number of T cell dysfunctions have been observed in the elderly. The most widely observed is the inability of these cells to proliferate at a level comparable to T cells from young individuals after stimulation by mitogens. To better characterize T cell impairment, we have focused on the in vitro T cell activation, analyzing by flow cytometry the activation molecules CD69 and CD71 on mitogen-stimulated lymphocytes from young and elderly subjects. The results show that the percentages of CD69+ and CD71 + T cells were significantly decreased in cultures from elderly subjects when compared to values obtained culturing cells from young individuals. The differences observed seem not due to differences in CD4 and CD8 rates in the "old' cells that underwent activation, since, following activation, the pattern of CD4 and CD8 phenotypes was the same in both groups of subjects. Signals from CD69 are relevant in controlling cytokine gene expression because its stimulation leads to interleukin-2 production and increases its receptor expression. The interaction of this cytokine with its cellular receptor is an essential requirement for T lymphocytes to express CD71 and to start proliferation. Thus, a key role in the age-associated impairment of T cell activation could be played by an ineffective modulation of CD69 expression suggesting a defect in the signal transduction pathway of the T cell receptor-CD3 complex in elderly.
Assuntos
Antígenos CD/sangue , Antígenos de Diferenciação de Linfócitos B/sangue , Antígenos de Diferenciação de Linfócitos T/sangue , Ativação Linfocitária , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Feminino , Humanos , Lectinas Tipo C , Masculino , Receptores da TransferrinaRESUMO
It is well known that in the elderly a deterioration of immune functions may occur. Particularly, stimulation of T cells from aged individuals leads to different kind and/or size of responses if compared with the responses obtained from T cells from young individuals. At the same time, an increase in prevalence of autoantibodies occurs in elderly. The altered production of certain cytokines might explain this paradox of decreased responsiveness to foreign antigens in the face of an increased response to self-antigens. We and others have suggested that this kind of immune response might depend on an age-associated impairment of Th-1 type function that selectively affects production of cytokines involved in the control of cellular responses. In contrast, Th-2 type function is seemingly not affected in elderly, as suggested by normal in vitro production of cytokines involved in humoral responses. To strengthen this hypothesis, in this study we have analysed the influence of age on the ability of mitogen-stimulated cultures of peripheral blood mononuclear cells from human beings to produce another Th-2 type cytokine, i.e. interleukin-5 (IL-5). IL-5 content of both 24- and 48-h stimulated cultures from old individuals was greater than that of young ones, although this difference attained significance only at 48 h. We suggest that the decreased production of Th-1 type cytokines in the presence of a normal or even increased production of Th-2 type cytokines might account for the pattern of immune response which may be observed in elderly, i.e. a normal or increased humoral response, including an autoimmune one, in the face of a low cell mediated immune response.
Assuntos
Envelhecimento/imunologia , Autoimunidade/fisiologia , Interleucina-5/biossíntese , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/imunologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Eosinófilos/imunologia , Feminino , Humanos , Imunoglobulina A/análise , Ativação Linfocitária , Masculino , Pessoa de Meia-IdadeRESUMO
Defects involving cellular expression of activation molecules, cell mediated immune response and natural killer (NK) activity are commonly observed in the elderly. Herein, data are reported on the evaluation of IL-12 production by old subjects. IL-12 is, actually, considered the key molecule for the induction of a T helper 1 (Th1) -type and NK response. IL-12 production from old subjects peripheral blood mononuclear cells (PBMNC) was evaluated using T-independent (bacterial lipopolysaccharide, LPS) or -dependent (phytoemagglutinin, PHA; immobilized anti-CD3 monoclonal antibodies, anti-CD3) mitogens. The IL-12 production after LPS stimulation was not reduced in cultures from old subjects when compared to that from young ones. On the contrary, IL-12 production by PHA or anti-CD3 stimulated PBMNC from old subjects was decreased. Furthermore, we have demonstrated a reduced CD40 and CD40 ligand (CD40L) expression on PBMNC from old subjects. This finding fits very well with the reduced cytokine production observed in the T-dependent stimulation systems, being the CD40-CD40L interaction mandatory for an efficient IL-12 production. All together, these results seem to suggest that defects in cell expression of activation molecules can affect the IL-12 secretion and in consequence other Th1-type cytokines.
Assuntos
Envelhecimento/imunologia , Interleucina-12/metabolismo , Leucócitos Mononucleares/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD40/biossíntese , Ligante de CD40 , Células Cultivadas , Feminino , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Glicoproteínas de Membrana/biossíntese , Mitógenos/farmacologia , Fito-Hemaglutininas/farmacologiaRESUMO
Despite a large number of studies, available data do not allow at present to reach definitive and clear conclusions on role of HLA on longevity, owing to major methodological problems, such as serological and molecular typing of different loci, insufficient sample sizes, different inclusion criteria and age cut-off, inappropriate mixing of data referred to people from 58 to over 100 years of age, inappropriate control matching, and neglected consideration of sex-related effects and the different genetic make-up of studied populations. However, within this confused scenario, some data emerge. First, two studies that do not fit the biases above discussed show that some HLA alleles are associated with longevity. However, some of these alleles may confer an increased risk to undergo a variety of diseases. Second, longevity may be associated with an increased homozygosity at HLA loci. Third, an intriguing association between longevity and the 8.1 ancestral haplotype (AH), which has been proven to be associated with a variety of immune dysfunctions and autoimmune diseases, apparently emerges. This association appears to be a sex-specific (males) longevity contributor, and it is particularly interesting, taking into account that a type 2 (early infancy) --> type 1 (adulthood) --> type 2 (aging) shift of cytokine profile occurs lifelong, and that individuals bearing this haplotype show a type 2 immune responsiveness (note that type 1 cytokines mainly enhance cellular responses, whereas type 2 cytokines predominantly enhance humoral responses). On the whole, the (sex specific) association of longevity with alleles or haplotypes of several genes related to risk factors for a variety of diseases (cardiovascular diseases, cancer), including HLA alleles and haplotypes, is not unexpected on the basis of previous studies on the genetics of longevity in centenarians. This association can be interpreted under the perspective of a well known evolutionary theory of aging (antagonistic pleiotropy). This theory predicts that the same gene (or allele or haplotype) can have different roles (positive or negative) in different periods of the life span. Thus, the 8.1 AH should exert a positive effect during the infancy and aging but not in adulthood, when, indeed it is associated to susceptibility to a variety of diseases.
Assuntos
Envelhecimento/genética , Antígenos HLA/genética , Longevidade/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/imunologia , Feminino , Antígenos HLA/classificação , Antígeno HLA-B8/classificação , Antígeno HLA-B8/genética , Antígeno HLA-DR3/classificação , Antígeno HLA-DR3/genética , Haplótipos , Homozigoto , Humanos , Longevidade/imunologia , MasculinoRESUMO
Healthy subjects carrying the HLA-B8,DR3 haplotype may show a large number of immune dysfunctions. Concerning T-cell dysfunctions, the most intriguing is a defect of the early phases of T-cell activation, responsible for the impairment of in vitro mitogen-stimulated cytokine production. Regarding B-cell dysfunctions, one the most fascinating topics is the association between this haplotype and IgA deficiency in healthy blood donors. Accordingly, HLA-B8,DR3-positive healthy subjects show significantly lower values of serum IgA than HLA-B8,DR3-negative ones. Because IL-5 is a stimulating factor for the secretion of IgA by committed B cells, we have analyzed the in vitro mitogen-stimulated IL-5 production by MNCs from healthy HLA-B8,DR3-positive individuals to study whether they display an impaired production of IL-5. The results clearly demonstrate that MNCs from HLA-B8,DR3-positive individuals display significant reduction of IL-5 production, suggesting that IgA synthesis dysregulation observed in HLA-B8,DR3-positive subjects could be due to an impairment of IL-5 production.
Assuntos
Antígeno HLA-B8/genética , Antígeno HLA-DR3/genética , Deficiência de IgA/genética , Imunoglobulina A/biossíntese , Interleucina-5/biossíntese , Adulto , Feminino , Haplótipos/imunologia , Humanos , Deficiência de IgA/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-IdadeRESUMO
The 8.1 ancestral haplotype (AH) is a common Caucasoid haplotype carried by most people who type for HLA-B8,DR3. It seems unique in its association with a wide range of immunopathologic diseases. Healthy subjects bearing this haplotype demonstrate several alterations of immune response. This article will focus on the identification of the mechanism(s) of disease susceptibility of 8.1 AH. In 13 carriers of 8.1 AH, and 43 negative patients, enzyme immune assays serum levels of tumor necrosis factor (TNF)-alpha, soluble endothelial leukocyte adhesion molecule-1 (sELAM-1), cortisol, and interleukin(IL)-10 were determined. In addition, quantification of cytokine produced in vitro after mitogen stimulation was studied, and all subjects were genotyped for alleles at -592, -819, and -1082 nucleotides of IL-10 gene 5' flanking region, which is known to control IL-10 production. Results revealed that 8.1 AH is associated with a high in vivo and in vitro production of TNF-alpha, which in turn seems responsible for increased serum levels of sELAM-1, cortisol, and IL-10. On the contrary, in vitro production of IL-10 is not increased in these patients and there are no differences in allele promoter frequencies between the two groups that might explain the differences in IL-10 serum values. Thus, serum values seem to be the result of the effects of increased serum levels of TNF-alpha and cortisol. In conclusion, the increased spontaneous release of TNF-alpha, which modifies a certain number of immunologic parameters, may be the most characterizing feature of 8.1 AH. The consequent modification of the immunologic scenario might be involved in the predisposition to the impressive number of diseases and the changes in immune response observed in the patients studied.
Assuntos
Doenças Autoimunes/genética , Predisposição Genética para Doença , Antígeno HLA-B8/genética , Antígeno HLA-DR3/genética , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Adulto , Doenças Autoimunes/imunologia , Células Cultivadas , Selectina E/sangue , Feminino , Haplótipos/genética , Haplótipos/imunologia , Humanos , Hidrocortisona/sangue , Interleucina-10/biossíntese , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
Aging is associated with alterations of the immune system, thought to be related to an increased susceptibility to infectious diseases, and possibly to cancer and autoimmunity in the elderly. In the present paper we report data obtained on freshly collected blood from 148 healthy subjects of different ages (from cord blood to 102 years old). The subjects were divided into seven age classes (cord blood, 3-11 years, 15-39 years, 41-60 years, 61-74 years, 75-84 years, 85-102 years) and their lymphocyte subsets and the expression of the apoptosis-related molecule CD95 were evaluated. In respect of lymphocyte subsets, the major differences were found in the cord-blood samples compared with the oldest old groups. In the cord-blood group, the absolute number of all the lymphocyte subsets was enhanced, but in the oldest group, an increase of CD16+ lymphocytes was observed, whereas CD19+ lymphocytes, which progressively decrease with age, continue to decrease further in the very old. The data show that the expression of CD95 increases until age 74 years, whereas in the oldest old it tends to decrease again. The trend of CD95 expression seems to be related to the change of expression of CD95 on CD4+ lymphocytes, because the CD8+/CD95+ population rose steadily throughout the entire age range. The evaluation of CD95+/CD45R0+ lymphocytes shows similar results to those observed analyzing CD95 on total lymphocytes. Furthermore, a constant increase of CD95+/CD28+ and a related decline of CD28+ lymphocytes was observed in all age groups. These data suggest that the expression of CD95 on the different subsets of lymphocytes can be considered a good marker for studies of immunosenescence, because it may be predictive of successful aging, and can partially explain the change in lymphocytes subsets in elderly.
Assuntos
Envelhecimento/imunologia , Regulação da Expressão Gênica no Desenvolvimento/imunologia , Linfócitos/imunologia , Receptor fas/genética , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Envelhecimento/genética , Antígenos CD/genética , Criança , Pré-Escolar , Feminino , Sangue Fetal , Humanos , Recém-Nascido , Contagem de Leucócitos , Contagem de Linfócitos , Subpopulações de Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologiaRESUMO
In the present paper we have evaluated IgD serum levels of 84 randomly selected HLA-typed healthy Sicilians. The values were analysed according to age, sex and HLA-DR phenotypes. No correlation between age and IgD serum levels was found in our population since all subjects were in a narrow age range. Furthermore, no significant association was found between IgD serum levels and gender of studied subjects. The evaluation of IgD serum levels according to HLA-DR phenotypes revealed that HLA-DR1 positive subjects displayed significantly higher values. These results are in agreement with previous reports showing that HLA phenotypes may be involved in the control of serum immunoglobulin levels. Furthermore, present data strengthen our suggestion that HLA-DR1 phenotype is related to the 'high responder' immunological profile.
Assuntos
Antígenos HLA-DR/genética , Imunoglobulina D/análise , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Valores de ReferênciaRESUMO
Selective IgA deficiency (IgA-D) is associated with the expression of some human leukocyte antigens (HLA) haplotypes and Major Hystocompatibility Complex (MHC) gene products have been suggested to be involved in the regulation of IgA synthesis. Recently, we have obtained evidences indicating that MHC influences the production of IgA and interleukin-5 (IL-5) both in humans and in mice. Lymphnode cells from pychril chloride (PC1) immunised BALB/c mice (bearing the H-2d haplotype) fail to produce IL-5 when stimulated in vitro with PC1 and this correlates with low antigen specific IgA production in vivo. In contrast using congenic BALB/k mice (bearing the H-2k haplotype) an high production both of IL-5 and of PC1-specific IgA is observed. Moreover, in vivo or in vitro administration of IL-5 to BALB/c mice was able to increase the production of antigen specific IgA. Similar evidences have been obtained by evaluation of the HLA influence on circulating immunoglobulin levels and interleukin production in normal HLA typed subjects. In fact HLA-B8, DR3 positive subjects show reduced level of serum IgA and their peripheral blood mononuclear cells stimulated with mitogen produce significantly reduced amounts of IL-5, IL-12, IL-2 and Interferon-gamma. We hypothesise that HLA-B8, DR3 associated IgA deficiency, known to be asymptomatic, can be due to a lack of subsequent signals, in particular of IL-5, involved in the late regulation of B cell differentiation. Preliminary evidences demonstrating that low amounts of human recombinant IL-5 are able to reconstitute IgA production by cells from HLA-B8, DR3 IgA-D subjects, seem to confirm this hypothesis.
Assuntos
Deficiência de IgA/etiologia , Deficiência de IgA/imunologia , Interleucina-5/biossíntese , Complexo Principal de Histocompatibilidade , Animais , Ligação Genética , Antígeno HLA-B8 , Antígeno HLA-DR3 , Humanos , Deficiência de IgA/genética , Imunoglobulina A/biossíntese , Técnicas In Vitro , Interleucina-5/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Biológicos , Proteínas Recombinantes/farmacologiaRESUMO
Hereditary angioedema (HAE) is a disease related to a complement disorder, namely a deficiency of C1 esterase inhibitor. Complement-split products are implicated in the regulation of the immune response, and we have compared some immunologic parameters between HAE and normal individuals. T-lymphocytes with receptors for IgG were increased in HAE, but no difference in T-cell suppressor activity for B-cells was detected. Furthermore, increased IgG receptor expression was not accompanied by any significant changes in the ratios of OKT4- and OKT8-defined antigens. Numbers of peripheral mononuclear cells (MNC) detected by alpha-naphthyl acetate esterase (ANAE) staining positivity were not significantly modified in HAE patients, although there was a trend toward higher absolute numbers of them showing paranuclear localization of ANAE. HAE patients had significantly reduced numbers of Langerhans cells (LC) showing different morphology and localization patterns. These observations are discussed in terms of differential membrane arrangements related to particular stages of cell activation, possibly attributable to continual complement activation resulting from a lack of control by C1 esterase inhibitor.
Assuntos
Angioedema/imunologia , Células de Langerhans/patologia , Receptores de Antígenos de Linfócitos T/análise , Linfócitos T/imunologia , Adulto , Angioedema/genética , Angioedema/patologia , Anticorpos Monoclonais , Contagem de Células , Feminino , Imunofluorescência , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Monócitos/patologia , Pele/imunologia , Pele/patologia , Linfócitos T Reguladores/imunologiaRESUMO
The authors have studied the HLA genotypes in 17 Sicilian coeliac children, in their parents and in their healthy brothers. A positive association has been found between coeliac disease (C.D.) and HLA antigens; this was strongest firstly for DQW2 and than for DR7 and DR3. Those antigens however do not result specific for C.D., because they were present in healty-control population too and because one coeliac patient was DQW2, DR7 and DR3 negative. A distortion of vertical transmission of HLA haplotypes has been observed in the studied patients, and this occurred for DR3/DQW2 that was transmitted mainly by paternal way. Moreover, in the healty brothers of our coeliac subjects a significant reduction of HLA antigens DQW2, DR7 and DR3 has not been found. Those observation and the finding that in our families the responsible gene for C.D. seems to have a low penetrance, should induce to search others genetic markers for coeliac disease.