Involvement Of Cellular Immunity Research Articles

Differences in immune response in patients with chronic opisthorchiasis invasion related to clinical manifestations of hepatobiliary system diseases

The aim of the study was to identify differences in the immune response in chronic opisthorchiasis with or without clinical manifestations of hepatobiliary system diseases. A comparison of laboratory parameters of immune system functioning (lymphocyte phenotypes detected by flow cytometry, concentrations of immunoglobulins and cytokines, indicators of nonspecific resistance) in patients with chronic opisthorchiasis (caused by Opisthorchis felineus) lacking clinical manifestations and with manifestations of cholecystitis, cholangitis, pancreatitis, gastritis, gastroduodenitis, confirmed by ultrasound and FGDS. It was found that the immunological parameters of the innate immune response were increased in all patients with chronic opisthorchiasis compared with the control group of apparently healthy subjects, which indicates activated macrophage-phagocytic arm in patients with opisthorchiasis invasion. The indicator of the stimulated NBT test is maximal in chronic opisthorchiasis without hepatobiliary system diseases, in case of comorbidity with such diseases it declines, but remains significantly higher than the values of the control group. This may be due to the exhaustion in the reserve capabilities of bactericidal neutrophil systems in patients with symptoms of damage to the hepatobiliary system due to prolonged inflammation. Indicators of the cellular arm in patients with chronic opisthorchiasis without clinical manifestations of hepatobiliary system diseases demonstrate a decrease in the absolute and relative level of cytotoxic T-lymphocytes. In the group with picture of hepatobiliary system disorders, an even deeper imbalance of indicators is revealed: the relative and absolute level of lymphocytes, the absolute count of T-lymphocytes are reduced, which may indicate about involvement of cellular immunity in the pathogenesis of complications of chronic opisthorchiasis. In all examined patients with chronic opisthorchiasis, the humoral immune response was also activated the total immunoglobulin E was significantly increased; at the same time, in patients with hepatobiliary system lesions, this parameter increases even more and a decrease in B-lymphocytes is detected. In all patients with chronic opisthorchiasis, there is also an increased level of proinflammatory cytokine IL-8, which rises even more in the group with hepatobiliary system diseases. The data obtained indicate the involvement of all arms of the immune response in a prominent inflammatory process when chronic opisthorchiasis is complicated by clinically overt hepatobiliary system diseases: the degree of deviation in the indicators of the innate and adaptive immune response from the norm and from those in uncomplicated opisthorchiasis increases.

Memory CD8+ T cell compartment associated with delayed onset of Plasmodium falciparum infection and better parasite control in sickle-cell trait children.

ObjectivesStudy of individuals with protection from Plasmodium falciparum (Pf) infection and clinical malaria, including individuals affected by the sickle‐cell trait (HbAS), offers the potential to identify cellular targets that could be translated for therapeutic development. We previously reported the first involvement of cellular immunity in HbAS‐associated relative protection and identified a novel subset of memory‐activated NK cells that was enriched in HbAS children and associated with parasite control. We hypothesised that other memory cell subsets might distinguish the baseline profile of HbAS children and children with normal haemoglobin (HbAA).MethodsSubsets of memory T cells and NK cells were analysed by flow cytometry in paired samples collected from HbAS and HbAA children, at baseline and during the first malaria episode of the ensuing transmission season. Correlations between cell frequencies and features of HbAS‐mediated protection from malaria were determined.ResultsHbAS children displayed significantly higher frequency of memory CD8+ T cells at baseline than HbAA children. Baseline frequency of memory CD8+ T cells correlated with features of HbAS‐mediated protection from malaria. Exploration of memory CD8+ T cell subsets revealed that central memory CD8+ T cell frequency was higher in HbAS children than in HbAA children.ConclusionThis study shows that HbAS children develop a larger memory CD8+ T cell compartment than HbAA children, and associates this compartment with better control of subsequent onset of infection and parasite density. Our data suggest that central memory CD8+ T cells may play an important role in the relative protection against malaria experienced by HbAS individuals, and further work to investigate this is warranted.

Th1/Th2 Cells and Associated Cytokines in Acute Hepatitis E and Related Acute Liver Failure

Background and Aims The involvement of cellular immunity in the development of hepatitis E virus (HEV) infection is rare. We aimed to study the roles of viral load and Th cell responses in acute hepatitis E (AHE) and HEV-related acute liver failure (HEV-ALF). Methods We evaluated viral load and Th1/Th2 cytokine levels in 34 patients with HEV infection, including 17 each with AHE or HEV-ALF. Seventeen healthy controls (HCs) were also included who were negative for anti-HEV IgM and IgG. Results There was no significant difference in viral load and HEV RNA in the AHE and HEV-ALF groups (both P > 0.05). The Th lymphocyte levels (CD3+, CD4+) in the AHE and HEV-ALF groups were significantly higher than those in the HC group (both P < 0.05), but there was no significant difference between the AHE and HEV-ALF groups (P > 0.05). Both IFN-γ and IL-10 showed gradual upward trend from the HC group to the AHE (both P < 0.01), but IFN-γ showed a sharp downward trend from the AHE group to the HEV-ALF group (P < 0.01) and IL-4 showed gradual upward trend from the AHE group to the HEV-ALF group (P < 0.01).There was no significant difference in Th1 and Th2 cytokines between the HEV RNA(+) group and HEV RNA(-) group (all P > 0.05). Th2 bias was observed from the AHE (ratio = 58.65) to HEV-ALF (ratio = 1.20) groups. The level of IFN-γ was associated with the outcome of HEV-ALF patients. Conclusions HEV viral load was not associated with aggravation of AHE, and the HEV-ALF patients showed significant Th2 bias, which may be involved in the aggravation of AHE.

Autoimmune response against tyrosinase induces depigmentation in C57BL/6 black mice

Regulation of melanogenesis by tyrosinase has now become an attractive approach for treatment of vitiligo but still the role of tyrosinase in the induction of depigmentation remains largely unexplored. This study was explored the role of tyrosinase in the induction of autoimmune depigmentation in C57BL/6 mice. Depigmentation was induced in C57BL/6 mice by tyrosinase immunization. Induced depigmentation was characterized by visual detection and was verified by histopathological analysis of lesional and non-lesinal skin biopsies. Moreover, induced depigmentation was re-validated by gene expression analysis of vitiligo-relevant genes by Taqman assays. Immunization of C57BL/6 mice by tyrosinase induces depigmentation on hairs as well as on skin. Immunoassays with Protein A-purified immune IgGs showed high titre antibodies against tyrosinase. Histopathological analysis showed that the total melanocytes were depleted from the basal layer of the epidermis and also from the dermis of depigmented lesions. The gene expression of vitiligo-relevant genes TYRP1, DCT, MLANA, MCIR, POMC, FOXJ2, CSNK1G3, SOX10, PMEL and KIT was significantly low in lesional skin as compared with non-lesional skin (p < .05). In contrast, the mRNA expression of CASP3 and NFκB1 was significantly high in lesional skin of depigmented mice as compared with non-lesional skin (p < .05). Furthermore, involvement of cellular immunity in depigmentation was confirmed by the reduction of CD4+:CD8+ lymphocytes ratio. In conclusion, this study shows that the autoimmune response against tyrosinase induces depigmentation in black C57BL/6 mice. The data obtained from the lesional and non-lesional skin biopsies showed the same features as were reported in human vitiligo patients.

MVA Vectored Vaccines Encoding Rift Valley Fever Virus Glycoproteins Protect Mice against Lethal Challenge in the Absence of Neutralizing Antibody Responses.

In vitro neutralizing antibodies have been often correlated with protection against Rift Valley fever virus (RVFV) infection. We have reported previously that a single inoculation of sucrose-purified modified vaccinia Ankara (MVA) encoding RVFV glycoproteins (rMVAGnGc) was sufficient to induce a protective immune response in mice after a lethal RVFV challenge. Protection was related to the presence of glycoprotein specific CD8+ cells, with a low-level detection of in vitro neutralizing antibodies. In this work we extended those observations aimed to explore the role of humoral responses after MVA vaccination and to study the contribution of each glycoprotein antigen to the protective efficacy. Thus, we tested the efficacy and immune responses in BALB/c mice of recombinant MVA viruses expressing either glycoprotein Gn (rMVAGn) or Gc (rMVAGc). In the absence of serum neutralizing antibodies, our data strongly suggest that protection of vaccinated mice upon the RVFV challenge can be achieved by the activation of cellular responses mainly directed against Gc epitopes. The involvement of cellular immunity was stressed by the fact that protection of mice was strain dependent. Furthermore, our data suggest that the rMVA based single dose vaccination elicits suboptimal humoral immune responses against Gn antigen since disease in mice was exacerbated upon virus challenge in the presence of rMVAGnGc or rMVAGn immune serum. Thus, Gc-specific cellular immunity could be an important component in the protection after the challenge observed in BALB/c mice, contributing to the elimination of infected cells reducing morbidity and mortality and counteracting the deleterious effect of a subneutralizing antibody immune response.

Focal segmental glomerular sclerosis: do not overlook the role of immune response

Focal and segmental glomerular sclerosis (FSGS) is a histological pattern characterized by the partial sclerosis of some, but not all, glomeruli. It may be secondary to diverse etiologies such as mutations of podocyte key genes, loss of nephrons, drugs, and virus infection. However, in most cases of FSGS, the etiology is unknown and these forms are called idiopathic (primary) FSGS. A number of different pathogenic hypotheses have been proposed. The frequent recurrence of nephrotic proteinuria after renal transplantation has attracted the attention to search for plasma factors eventually implicated in the pathogenesis. However a decisive and unifying hypothesis is still lacking. On the other hand, recent findings indicate the involvement of cellular immunity and possibly autoantibodies in the pathogenesis of some forms of FSGS. In this paper we report on the recent advances in the pathophysiology of idiopathic FSGS and suggest the possibility that at least some forms of idiopathic FSGS may be caused by autoimmune reactivity.

Study on the T-helper cell 1/2 cytokine profile in blister fluid of patients with herpes zoster and its clinical significance

Herpes zoster (HZ) is a Varicella zoster virus infection disease. Previous studies have presumed the connection between development of HZ and involvement of cellular immunity in peripheral blood. However, whether cellular immunity plays a role in the local skin lesion has not been addressed. To explore the levels of T-helper cell (Th)1/Th2 type cytokine profiles in the blister fluid of the skin lesions from the patients with HZ and its role in pathogenesis, we used the cytometric bead array kit to compare the levels of cytokines (interleukin [IL]-2, tumor necrosis factor [TNF]-α, IL-10 and IL-4) in blister fluid from 46 patients with those from the suction blister fluids from 20 volunteers without any infectious disease (the control group). The results indicated that the levels of Th1 cytokines, IL-2 and TNF-α in the blister fluid from the patients' skin lesions were significantly lower than those from the control group, whereas the levels of Th2 cytokines IL-10 and IL-4 were significantly higher than those in the control group. Moreover, significant variation of the levels of Th1/Th2 cytokines (IL-2, TNF-α, IL-10 and IL-4) in the blister fluid from the HZ patients' lesions was also observed among different stages of the disease. It is concluded that a cytokine imbalance was present in the local lesions of patients with HZ during disease development. Our data suggested that the Th immunity was associated with disease activity, which may play an important role in the pathogenesis of HZ.

Lymphocyte imbalance in vitiligo patients indicated by elevated CD4+/CD8+ T-cell ratio

Vitiligo is a disorder of pigmentation associated with an autoimmune-mediated loss of melanocytes from the epidermis. Humoral immunity and the involvement of cellular immunity have been investigated in the pathogenesis of vitiligo. We evaluated the role of pro-inflammatory cytokines and lymphocyte fractions in peripheral blood in a cohort of Austrian patients with vitiligo. Morning blood samples from 40 patients with vitiligo were collected. Twenty-one patients had active and 19 had stable vitiligo disease. All patients were suffering from non-segmental vitiligo at different stages of the disease. Sixteen persons presented with an additional autoimmune thyroid disease. To evaluate a possible involvement of proinflammatory cytokines in vitiligo we measured sTNF-RI (soluble tumour necrosis factor receptor I), IL-6 and additionally CIC (circulating immune complexes). We compared these findings to the data from matched normal persons. To investigate the mechanisms of cellular immunity, peripheral blood cell count and lymphocyte subtype analysis by flow cytometry were done. sTNF-RI, IL-6 and CIC serum levels were in the normal range. In the patient group median sTNF-RI level was 1.5 ng/ml and median CIC level was 35.2 microg/ml, and no statistically significant differences to the control group were observed. Median IL-6 level in vitiligo patients was 2.7 pg/ml and in the normal range-but higher than the median level of 0.5 pg/ml observed in normal persons (p < 0.001). Absolute and relative counts of lymphocyte subtypes were normal. The ratio of CD4+/CD8+ T-cells had an elevated median value of 2.6 [quartiles 2.0; 3.1]. 61% of the vitiligo patients had a ratio higher than 2.4, which was the normal cut-off point. In most vitiligo patients the balance of cytotoxic/suppressor and helper/inducer T-cells in peripheral blood is disturbed which might lead to a predominance of T-cell subtypes in the intracutaneous site of autoimmune melanocyte loss.

Commentary 4

I firmly believe that vitiligo is an autoimmune disease in which autoreactive, melanocyte-specific cytotoxic T lymphocytes (CTL) escape central tolerance, break peripheral tolerance and destroy epidermal melanocytes. The evidence in favour of the autoimmune genesis of vitiligo is highly convincing. Suppression of immune reactivity by various effective treatments suggests that their immunosuppressive mechanism interferes with that which leads to the destruction of melanocytes (1-6). The association of vitiligo with other autoimmune diseases is well known (7-9). The presence of circulating anti-melanocyte antibodies points to a possible involvement of humoral immunity, while the involvement of cellular immunity is indicated by lymphocyte infiltration at the margin of lesions. In particular, the presence of cellular infiltrates during the progressive loss of melanocytes from depigmenting vitiligo skin (10) and the detection of T cells juxtapositionally apposed to remaining melanocytes (11) demonstrate the early implication of cellular immunity in the pathogenesis of the disease. Other views, however, exist. Intrinsically increased sensitivity of melanocytes to oxidative stress is said to be pathogenic. This, however, can be no more than a conjecture in the total absence of any experimental demonstration that it is a primary event. Fault can also be found with the postulation of an inappropriate reaction to neuropeptides as the leading cause. Their concentration in vitiligo skin is not sufficient to kill melanocytes, while the time course of their production is such as to rank them as a consequence rather than a cause (12). These and other proposed pathogenetic mechanisms have very little to offer in the way of proof. The point is ‘what immune cells are pathogenic? Melanocyte-specific autoantibodies are certainly present (13-17), but their pathogenic role is a mystery. The patchy distribution of cutaneous depigmentation and the very frequent symmetrical distribution of lesions fit in well with the view that autoimmune melanocyte destruction is induced by lymphocyte clones with affinities for specific areas of skin (18). We and others (19-21) have demonstrated the presence of high frequencies of melanocyte-specific CTL in the peripheral blood of patients with vitiligo. These autoreactive CTL are functionally intact and kill normal melanocytes in vitro. They display high avidity of antigen recognition and express the skin-homing receptor CLA (22). Overall, these findings strongly support an association between the presence of melanocyte-specific CTL and vitiligo, and directly point to their pathogenic role in this disease. Investigation of the association of vitiligo with melanoma has clarified the role of autoreactive CTL in its development. Identical clonally expanded CTL have been detected in a regressing melanoma and in the vitiligo-like halo surrounding the tumor (23). These and other findings assume that antigen-specific proliferation is involved in the destruction of normal and malignant melanocytes (24-26). Work from our group has contributed to the current opinion that vitiligo T cells demonstrate reactivity to antigens previously recognized as target antigens for T cells infiltrating melanoma tumors (20, 22, 27). Interestingly, in a comparison with melanoma-derived T cells, vitiligo T cells displayed greater reactivity towards melanoma cells (28). We believe that high avidity of antigen recognition represents a peculiar property of anti-melanocytic CTL from patients with vitiligo that contributes to their abnormal reactivity (29). In conclusion, melanocyte-specific CTL with high-affinity T-cell receptors most likely escape clonal deletion in the thymus and enter the circulation. By expressing CLA, they home to the skin where they express type 1 cytokine profiles and mediate melanocyte destruction. The immunological imbalances thus created may be supposed to herald the processes that also initiate a biochemical or neural mechanism for the destruction of melanocytes. Cellular autoimmunity can therefore be proposed as the sole cause and origin of vitiligo.

Molecular survival strategies of Echinococcus multilocularis in the murine host

Larval infection with Echinococcus multilocularis starts with the intrahepatic postoncospheral development of a metacestode that—at its mature stage—consists of an inner germinal and an outer laminated layer (GL & LL). In certain cases, an appropriate host immune response may inhibit parasite proliferation. Several lines of evidence obtained in vivo and in vitro indicate the important bio-protective role of the LL. For instance, the LL has been proposed to protect the GL from nitric oxide produced by periparasitic macrophages and dendritic cells, and also to prevent immune recognition by surrounding T cells. On the other hand, the high periparasitic NO production by peritoneal exsudate cells contributes to periparasitic immunosuppression, explaining why iNOS deficienct mice exhibit a significantly lower susceptibility towards experimental infection. The intense periparasitic granulomatous infiltration indicates a strong host–parasite interaction, and the involvement of cellular immunity in control of the metacestode growth kinetics is strongly suggested by experiments carried out in T cell deficient mouse strains. Carbohydrate components of the LL, such as Em2(G11) and Em492, as well as other parasite metabolites yield immunomodulatory effects that allow the parasite to survive in the host. I.e., the IgG response to the Em2(G11)-antigen takes place independently of alpha-beta + CD4 + T cells, and in the absence of interactions between CD40 and CD40 ligand. Such parasite molecules also interfere with antigen presentation and cell activation, leading to a mixed Th1/Th2-type response at the later stage of infection. Furthermore, Em492 and other (not yet published) purified parasite metabolites suppress ConA and antigen-stimulated splenocyte proliferation. Infected mouse macrophages (AE-MØ) as antigen presenting cells (APC) exhibited a reduced ability to present a conventional antigen (chicken ovalbumin, C-Ova) to specific responder lymph node T cells when compared to normal MØ. As AE-MØ fully maintain their capacity to appropriately process antigens, a failure in T cell receptor occupancy by antigen-Ia complex or/and altered co-stimulatory signals can be excluded. Studying the status of accessory molecules implicated in T cell stimulation by MØ, it could be shown that B7-1 (CD80) and B7-2 (CD86) remained unchanged, whereas CD40 was down-regulated and CD54 (=ICAM-1) slightly up-regulated. FACS analysis of peritoneal cells revealed a decrease in the percentage of CD4+ and CD8 + T cells in AE-infected mice. Taken together the obstructed presenting-activity of AE-MØ appeared to trigger an unresponsiveness of T cells leading to the suppression of their clonal expansion during the chronic phase of AE infection. Interesting information on the parasite survival strategy and potential can be obtained upon in vitro and in vivo treatment. Hence, we provided very innovative results by showing that nitazoxanide, and now also, respectively, new modified compounds may represent a useful alternative to albendazole. In the context of chemotherapeutical repression of parasite growth, we searched also for parasite molecules, whose expression levels correlate with the viability and growth activity of E. multilocularis metacestode. Expression levels of 14-3-3 and II/3-10, relatively quantified by realtime reverse transcription-PCR using a housekeeping gene beta-actin, were studied in permissive nu/nu and in low-permissive wild type BALB/c mice. At 2 months p.i., the transcription level of 14-3-3 was significantly higher in parasites actively proliferating in nu/nu mice compared to parasites moderately growing in wild type mice. Immunoblotting experiments confirmed at the protein level that 14-3-3 was over-expressed in parasites derived from nu/nu mice at 2 months p.i. In vitro-treatment of E. multilocularis with an anti-echinococcal drug nitazoxanide for a period of 8 days resulted in a significant decrease of both 14-3-3 and II/3-10 transcription levels, which correlated with the kinetics of a housekeeping gene, beta-actin. This indicates that 14-3-3-exhibits a good potential as a molecular marker to assess viability and growth activity of the parasite.

Germination of the spore in the gastrointestinal tract provides a novel route for heterologous antigen delivery

We have evaluated the potential of endospores of the Gram-positive bacterium Bacillus subtilis as an oral vaccine delivery system. The key features of the B. subtilis spore as a vaccine are, non-pathogenicity, advanced cloning tools, extreme robustness, long-term storage properties and its current use as a probiotic for both humans and animals. We have shown previously that the spore germinates in the small intestine of the mouse and have exploited this attribute for heterologous antigen delivery in this work. The first part of this study was to evaluate the fate of spores in vivo as well as under simulated gut conditions. This showed that spores were extremely robust with most being excreted in the faeces. Using a recombinant gene expressing high levels of β-galactosidase specifically in the germinated spore (vegetative cell) we showed that spores administered orally could elicit β-galactosidase-specific local and systemic immune responses. This demonstrated proof of principle that the germinating spore might be effective in the safe delivery of antigens across the stomach barrier. Interestingly, analysis of IgG subclasses suggested a potential bias towards a Th1 response and the involvement of cellular immunity.

Natural killer (Nk) Cell activity and nk cell subsets in workers with a tendency of burnout

The involvement of cellular immunity in the burnout syndrome remains to be elucidated. We assessed three components of burnout of the Maslach Burnout Inventory: emotional exhaustion; depersonalization (DP); and personal accomplishment, as well as natural killer cell activity (NKCA) and NK cell subsets in 42 male workers. Workers with a higher DP score showed a lower NKCA and a lower proportionality of CD57 +CD16 + to total lymphocytes. There were no differences in any of the health behaviors (e.g., smoking, alcohol, or obesity) between workers showing higher burnout and those showing lower burnout. A stepwise multiple regressions analysis demonstrated that NKCA was closely correlated with DP, independent of other variables, including a stress index. These results suggest that the relationship between reduced cellular immunity and DP is not due to traditional work stress or health behavioral problems. Further studies on DP as a psychosomatic disorder as well as an occupational health problem should be performed in the future.

P-381 Apparent involvement of cellular immunity in the mechanism of hepatic cell damage and dysfunction associated with HCV hepatitis (CHC) patients

P-381 Apparent involvement of cellular immunity in the mechanism of hepatic cell damage and dysfunction associated with HCV hepatitis (CHC) patients

Distinct Neopterin Excretion Patterns after Vaccination

Summary To compare the involvement of cellular immunity in response to vaccination we have investigated urinary neopterin levels in daily follow-ups of children after vaccination with live measles/mumps vaccine and of adults after boosting with the soluble antigen tetanus toxoid. Neopterin levels distinctly peaked 8 - 11 days after vaccination with measles/mumps vaccine. In contrast, after boosting with soluble antigen tetanus toxoid neopterin levels remained unaffected. Large amounts of neopterin are produced by human monocytes/ macro phages on stimulation with gamma interferon. In patients neopterin concentrations reflect activation of cell mediated immunity. The data imply that distinct pathways of T cell activation are triggered in humans after immunization with live vaccine and with soluble antigen .

Cellular regulation of lung granuloma formation and delayed-type hypersensitivity induced with BCG cell walls further evidence of involvement of cellular immunity in lung granuloma formation

We have previously showed several evidences in which cellular immunity is involved in lung granuloma formation induced with oil-associated BCG cell wall (CW) vaccine. In the present study, we examined in mice the effects of thymectomy, splenectomy and the administration of cyclophosphamide on lung granuloma formation as well as BCG CW-induced footpad reactions to PPD, a prototype of delayed-type hypersensitivity (DTH). The results presented herein provide further evidence that cellular immunoregulatory mechanisms control the development of lung granuloma and DTH, and that lung granuloma formation is thymus- and spleen-dependent.