Cost-effectiveness of single-dose AmBisome pre-emptive treatment for the prevention of cryptococcal meningitis in African low and middle-income countries.

Cryptococcal antigen (CrAg) screening is recommended for patients with advanced HIV to reduce AIDS-related mortality. For asymptomatic CrAg-positive persons, fluconazole pre-emptive therapy is standard, despite a ∼25% failure rate. Single-dose liposomal amphotericin B (AmBisome) is non-inferior to standard treatment for cryptococcal meningitis. We evaluate the threshold of efficacy necessary for AmBisome + fluconazole to be cost-effective as pre-emptive therapy for CrAg-positive persons.We created a decision analytic model to evaluate CrAg screening and treatment in HIV-infected persons with CD4 < 100 cells/µL. Costs were estimated for screening, pre-emptive therapy, and hospitalization for an example low-income country (Uganda) and middle-income country (South Africa). We used a discounted price range of AmBisome® at ${\$}$16.25 to ${\$}$40 per 50 mg vial for both Uganda and South Africa. We estimated AmBisome efficacy from 75 to 95%. Parameter assumptions were based on prospective CrAg screening studies and clinical trials in Africa. Disability adjusted life years (DALYs) were calculated using the age-specific life expectancy in Uganda, per WHO Global Health Observatory data. We modeled the theoretical efficacy of adjunctive AmBisome to determine cost per DALY averted.In South Africa, at ${\$}$16.25 per vial cost and a minimum efficacy of 85%, adjunctive AmBisome is cost-saving compared to fluconazole monotherapy. Compared to fluconazole pre-emptive therapy in Uganda, AmBisome + fluconazole would cost ${\$}$475, ${\$}$220, or ${\$}$136 per DALY averted if meningitis-free survival efficacy was 80, 85, or 90% at ${\$}$24 per vial cost.Investing in AmBisome may be cost-effective in low-income settings compared to using fluconazole pre-emptive therapy alone, if efficacy is 85% or greater. AmBisome pre-emptive therapy appears more cost-efficient in middle-income settings where hospitalization costs for meningitis, and GDP per capita are higher. LAY SUMMARY: We evaluate the efficacy necessary for AmBisome + fluconazole to be cost-effective to prevent cryptococcal meningitis. We found that if AmBisome pre-emptive therapy has an efficacy of 85% or greater, it is likely to be cost-effective in low-income settings.

Neutrophil and CD4+ milk cell count related to natural incidence of mastitis in Jersey cattle.

This Research Communication describes the relation between somatic cells and microbial content in milk from Jersey cattle. Milk samples were classified in groups: healthy, dirty and mastitic (from Staphylococcus spp., Escherichia coli, Coliforms). The somatic cells in each of those groups were analysed by two methods - flow cytometric and automatic fluorescent cell counting. Those methods were compared. Total somatic cell count (SCC), neutrophil count, and lymphocytes with cluster of differentiation 4 (CD4+cells) were determined. There was a positive relationship between microbes and somatic cells. It was noticed that the neutrophil count was generally increased together with SCC, whilst the CD4+ cell count was higher in healthy milk samples (about 8%) compared to mastitic ones (about 3%). Lower number of CD4+ cells (from 1 to 4%) was determined in samples positive for Staphylococcus spp. but with lower SCC (from 2.7 to 4.0 × 105 cells/ml). Also, the number of CD4+ cells in Staphylococcus spp.-positive samples increased (to 4.8%) together with higher SCC, something that was not observed in the other mastitic samples. Knowledge of those relations could be useful for veterinary medical tests in the initial phase of inflammation.

Immunomodulatory effect of Acanthopanax senticosus polysaccharide on immunosuppressed chickens.

The immunomodulatory effect of Acanthopanax senticosus polysaccharide (ASPS) on immunosuppressed chickens induced by cyclophosphamide (Cy) was observed in this study. Four hundred 7-day-old chickens were randomly divided into 4 groups: vaccinated control group (VC group), Cy-challenged control group (Cy group), Cy-challenged + low-dose ASPS group (ASPSL + Cy group), and Cy-challenged + high-dose ASPS group (ASPSH + Cy group). All groups except the VC group were injected with Cy at a dose of 80 mg/kg/day of BW for 3 successive days to induce immunosuppression. At the age of 10 d, the ASPSL + Cy group and ASPSH + Cy group were intramuscularly injected with 0.2 mL of ASPS at the dose of 100 and 200 mg/mL/day, respectively, once a day for 3 successive days. The Cy group was injected with saline solution in the same way as the 2 ASPS groups. At the age of 14 d, the chickens were vaccinated with Newcastle disease (ND) vaccine in all groups. On day 7, 14, 21, and 28 after the vaccination, BW, lymphocyte proliferation, the serum antibody titers of the ND vaccine, the proportion of CD4+ and CD8+ T lymphocytes, and the concentrations of interferon gamma and IL-2 were determined. The results showed that chickens were injected with Cy at a dose of 80 mg/kg of BW for 3 d displayed lower immune responses than the control group, indicating that the immunosuppressive model was successfully established. At most time points, both high and low doses of ASPS could significantly promote lymphocyte proliferation; enhance BW, antibody titers, and the proportion of CD4+ and CD8+ T lymphocytes; and raised the concentrations of interferon gamma and IL-2 in Cy-treated chickens compared with those in the Cy control group (P < 0.05). These results indicated that ASPS could resist immunosuppression induced by Cy and may be a new-type immune adjuvant to improve vaccination in normal and immunosuppressed chickens.

Lymphocyte Subsets in the Adrenal Glands of Dogs With Primary Hypoadrenocorticism.

Primary hypoadrenocorticism, or Addison's disease, is an autoimmune condition common in certain dog breeds that leads to the destruction of the adrenal cortex and a clinical syndrome involving anorexia, gastrointestinal upset, and electrolyte imbalances. Previous studies have demonstrated that this destruction is strongly associated with lymphocytic-plasmacytic inflammation and that the lymphocytes are primarily T cells. In this study, we used both immunohistochemistry and in situ hybridization to characterize the T-cell subtypes involved. We collected postmortem specimens of 5 dogs with primary hypoadrenocorticism and 2 control dogs and, using the aforementioned techniques, showed that the lymphocytes are primarily CD4+ rather than CD8+. These findings have important implications for improving our understanding of the pathogenesis and in searching for the underlying causative genetic polymorphisms.

Influence of orally fed a select mixture of Bacillus probiotics on intestinal T-cell migration in weaned MUC4 resistant pigs following Escherichia coli challenge.

Efficient strategies for treating enteritis caused by F4(+) enterotoxigenic Escherichia coli (ETEC)/verocytotoxigenic Escherichia coli (VTEC)/enteropathogenic E. coli (EPEC) in mucin 4 resistant (MUC4 RR; supposed to be F4ab/ac receptor-negative [F4ab/acR(-)]) pigs remain elusive. A low (3.9 × 10(8) CFU/day) or high (7.8 × 10(8) CFU/day) dose of Bacillus licheniformis and Bacillus subtilis spore mixture (BLS-mix) was orally administered to MUC4 RR piglets for 1 week before F4(+) ETEC/VTEC/EPEC challenge. Orally fed BLS-mix upregulated the expression of TLR4, NOD2, iNOS, IL-8, and IL-22 mRNAs in the small intestine of pigs challenged with E. coli. Expression of chemokine CCL28 and its receptor CCR10 mRNAs was upregulated in the jejunum of pigs pretreated with high-dose BLS-mix. Low-dose BLS-mix pretreatment induced an increase in the proportion of peripheral blood CD4(-)CD8(-) T-cell subpopulations and high-dose BLS-mix induced the expansion of CD4(-)CD8(-) T cells in the inflamed intestine. Immunostaining revealed that considerable IL-7Rα-expressing cells accumulated at the lamina propria of the inflamed intestines after E. coli challenge, even in pigs pretreated with either low- or high-dose BLS-mix, although Western blot analysis of IL-7Rα expression in the intestinal mucosa did not show any change. Our data indicate that oral administration of the probiotic BLS-mix partially ameliorates E. coli-induced enteritis through facilitating upregulation of intestinal IL-22 and IκBα expression, and preventing loss of intestinal epithelial barrier integrity via elevating ZO-1 expression. However, IL-22 also elicits an inflammatory response in inflamed intestines as a result of infection with enteropathogenic bacteria.

The effect of 1 year of trilostane treatment on peripheral lymphocyte subsets in dogs with pituitary-dependent hyperadrenocorticism.

This study investigated the changes in lymphocyte subsets during the trilostane medication of Pituitary-dependent hyperadrenocorticism (PDH) dogs. The cortisol level and lymphocyte subsets of eight dogs with PDH were monitored 0, 1, 3, 6, 9 and 12 months after the initiation of trilostane treatment. White blood cells (WBC), lymphocytes, CD3(+) (T lymphocyte), CD4(+) (helper T lymphocyte), CD8(+) (cytotoxic T lymphocyte) and CD21(+) (B lymphocyte) cells were measured. Although the post-ACTH stimulation test cortisol level was significantly lower during trilostane treatment, changes in the CD3(+), CD4(+), CD8(+) and CD21(+) counts were not observed. Meanwhile, significant decrease was observed in WBC counts during trilostane treatment. These indicate that long-term trilostane treatment has little effect on the lymphocyte subsets in PDH dogs.

Correlation of central memory CD4+ T-Cell decrease in the peripheral blood with disease progression in SIVmac251-infected Chinese rhesus macaques.

BACKGROUND: Correlation of CD4(+) Tcm cells in the peripheral blood to disease progression in SIVmac251 infection was examined in Chinese rhesus macaques. METHODS: Plasma viral RNA loads were measured by a quantitative real-time reverse transcription-PCR (qRT-PCR) assay for SIV gag. Disease progression was determined based on time of survival. Phenotyping of CD4(+) T-cell subsets in the peripheral blood was longitudinally performed by flow cytometry. RESULTS: Although CD4(+) T-cell decrease and low CD4(+)/CD8(+) T-cell ratio in the peripheral blood after SIVmac251 infection did not correlate with disease progression, CD4(+) Tcm cell decrease was observed to be correlated to disease progression in the SIVmac251-infected Chinese rhesus macaques. CONCLUSIONS: Our findings suggest that CD4(+) Tcm cell decrease could be used as a predictive marker for defining the pathogenesis of the SIV disease and consequently HIV/SIV vaccine efficacy in Chinese rhesus macaques.

Effect of supplemental vitamin E on the peripheral blood leukocyte population in Japanese Black calves.

We investigated the effect of supplemental vitamin E on the peripheral blood leukocyte population in Japanese Black calves. Twenty-six calves kept at the same farm were studied. They were divided into two groups; thirteen calves received 300 IU/day of vitamin E orally from 1 to 3 months of age (VE group), and the other thirteen calves did not receive the vitamin E supplement (control group). The VE group showed a higher serum vitamin E concentration at 2 and 3 months of age compared with the control group (P<0.01). The numbers of CD3(+) cells and CD4(+) cells were higher in the VE group than in the control group, and the difference was statistically significant at 3 months of age (P<0.05). The numbers of CD21(+) cells were higher in the VE group than in the control group, and the difference was statistically significant at 2 months of age (P<0.05). The numbers of CD335(+) cells tended to be higher in the VE group than in the control group. The numbers of CD8(+) cells and CD14(+) cells tended to be higher in the VE group than in the control group at 3 and 4 months of age. This study demonstrated that the supplementation of suckling Japanese Black calves with vitamin E might affect the numbers of some immune cell types in the peripheral blood.

Longitudinal assessment of T-lymphocyte subpopulations during generalized demodicosis in dogs and their relationship with remission.

BACKGROUND: The pathogenesis of canine generalized demodicosis is poorly understood but is thought to involve dysfunction of the immune system. Previous studies showed diminished CD4+ T lymphocyte counts in affected dogs, but none has evaluated this subpopulation through resolution of the disease. HYPOTHESIS/OBJECTIVES: In this longitudinal study, we tested whether quantification of CD4+ cells, CD8+ cells and the ratio of CD4+ to CD8+ cells are good indicators of immunological status and could be used as biomarkers of treatment efficacy and prognosis. ANIMALS: Sixteen dogs of several breeds with diagnoses of generalized demodicosis, plus 30 age/breedmatched healthy dogs. METHODS: Total lymphocytes, CD4+, CD8+ and CD4+:CD8+ ratio were quantified at four time points: at diagnosis, 30 days after diagnosis (during treatment), at first negative parasitological examination and at clinical cure. RESULTS: Absolute numbers of CD4+ cells were significantly lower in affected dogs at the time of diagnosis. Absolute numbers of CD4+ and CD8+ cells were significantly augmented in affected animals compared with control dogs after treatment was established, and this persisted until the first negative parasitological examination, at which time the CD4+ counts equalled those of the control group. CONCLUSIONS AND CLINICAL IMPORTANCE: Our findings suggest that longitudinal quantification of CD4+ and CD8+ T lymphocytes is a useful indicator of the efficacy of demodicosis treatment.

Increased numbers of peripheral blood CD34+ cells in dogs with canine atopic dermatitis.

BACKGROUND: The bone marrow may be involved in human atopic diseases, as shown by the release of CD34+ cells into the peripheral blood. HYPOTHESIS/OBJECTIVES: The aim was to determine the numbers of CD34+ cells in atopic dogs. ANIMALS: The following three groups of dogs were studied: 27 dogs with nonfood-induced atopic dermatitis (NFICAD); 16 dogs with nonallergic inflammatory diseases; and 13 healthy control dogs. METHODS: Dogs with NFICAD were selected after fulfilment of Favrot's criteria and exclusion of other pruritic dermatoses, including flea infestation and adverse reaction to foods. The Canine Atopic Dermatitis Extent and Severity Index (CADESI)-03 and a Visual Analog Scale (VAS) score for pruritus were used to quantify clinical signs. A phycoerythrin-conjugated anticanine CD34 antibody was used to stain peripheral blood CD34+ cells, and these were enumerated using a flow cytometer. The CD34+ cell counts were compared between groups and tested (in the NFICAD group) for correlation with the severity of clinical signs. RESULTS: The numbers of peripheral CD34+ cells in dogs with NFICAD (median 1.7) were statistically higher than in dogs with other nonallergic inflammatory diseases (median 1.0; P = 0.01) and healthy control dogs (median 0.9; P = 0.009). In dogs with NFICAD, there was no correlation between CD34+ cell numbers and CADESI-03 scores or owner-assessed pruritus (VAS score). CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study suggest the possible involvement of CD34+ cells in dogs with NFICAD. The role of CD34+ cells in the aetiopathogenesis of canine atopic dermatitis remains to be determined.

Influence of endogamy and mitochondrial DNA on immunological parameters in cattle.

BACKGROUND: Endogamy increases the risk of manifestation of deleterious recessive genes. Mitochondrial DNA allows the separation of American Zebu (Bos indicus and Bos taurus) and evaluate the effect of mitochondrial DNA on productive traits of cattle. However, the effect of endogamy and mitochondrial DNA (mtDNA) on the immune system remains unclear. The aim of this study was to evaluate the association between endogamy, mtDNA and immune parameters. RESULTS: A total of 86 cattle (43 cows and 43 calves) were used in this study. Age, endogamy, milk yield, and origin of mtDNA were measured and their influence on immunological parameters was evaluated. Older cows had increased CD4+ T cells, decreased CD21+ and γδhigh T cells as well as increased CD4+/CD8+ and T/B ratio. Multiple regression analysis indicated that endogamy in calves was associated with increased CD8+ T and CD21+ B lymphocytes, and decreased γδhigh T cells in peripheral blood. Cows with medium and lower endogamy had a lower percentage of B lymphocytes and γδlow T cells and cows with lower endogamy had higher levels of γδ T cells and γδhigh T cells, as well as the CD4+/CD48+ cell ratio. Calves with higher endogamy had higher levels of CD8+ T lymphocytes, whereas calves with lower endogamy had lower levels of γδlow T cells. CONCLUSIONS: These results demonstrated for the first time that endogamy influences the immune system of cattle.

Immunization with recombinant 3-1E protein in AbISCO®-300 adjuvant induced protective immunity against Eimeria acervulina infection in chickens.

Immunostimulating complexes (ISCOMs), a kind of novel antigen presenting system, could enhance immune protection by antigen presentation. AbISCO®-300 comprising purified saponin, cholesterol and phosphatidyl choline is an effective ISCOM adjuvant. To evaluate the immune protection of recombinant 3-1E protein against Eimeria acervulina infection, chickens were immunized with recombinant 3-1E protein in combination with AbISCO®-300 or recombinant 3-1E protein alone in this study. The protective immunity was assessed with body weight gain, fecal oocyst output, detection of intestinal IgA positive cells and percentages of CD3(+), CD4(+) or CD8(+) intestinal intraepithelial lymphocytes (IELs). Chickens vaccinated with different doses of recombinant 3-1E protein plus AbISCO®-300 showed higher percentages of CD3(+), CD4(+), and CD8(+) intestinal IELs, increased positive expression rate of intestinal IgA, increased body weight gains and decreased oocyst shedding compared with recombinant 3-1E protein-only vaccinated groups. The results showed that immunization with various doses of the recombinant 3-1E protein in AbISCO®-300 adjuvant enhanced immune protection against avian coccidiosis.

Flow cytometric characterization and clinical outcome of CD4+ T-cell lymphoma in dogs: 67 cases.

BACKGROUND: Canine T-cell lymphoma (TCL) is conventionally considered an aggressive disease, but some forms are histologically and clinically indolent. CD4 TCL is reported to be the most common subtype of TCL. We assessed flow cytometric characteristics, histologic features when available, and clinical outcomes of CD4+ TCL to determine if flow cytometry can be used to subclassify this group of lymphomas. OBJECTIVE: To test the hypothesis that canine CD4+ T-cell lymphoma (TCL) is a homogeneous group of lymphomas with an aggressive clinical course. ANIMALS: Sixty-seven dogs diagnosed with CD4+ TCL by flow cytometry and treated at 1 of 3 oncology referral clinics. METHODS: Retrospective multivariable analysis of outcome in canine CD4+ TCL including patient characteristics, treatment, and flow cytometric features. RESULTS: The majority of CD4+ TCL were CD45+, expressed low class II MHC, and exhibited an aggressive clinical course independent of treatment regimen (median survival, 159 days). Histologically, CD4+ TCL were classified as lymphoblastic or peripheral T cell. Size of the neoplastic lymphocytes had a modest effect on both PFI and survival in this group. A small number of CD4+ TCL were CD45- and class II MHC high, and exhibited an apparently more indolent clinical course (median survival not yet reached). CONCLUSIONS AND CLINICAL IMPORTANCE: Although the majority of CD4+ TCL in dogs had uniform clinical and flow cytometric features and an aggressive clinical course, a subset had a unique immunophenotype that predicts significantly longer survival. This finding strengthens the utility of flow cytometry to aid in the stratification of canine lymphoma.

Regulatory T cells, Cytotoxic T lymphocytes and a T(H)1 cytokine profile in dogs naturally infected by Leishmania infantum.

Canine leishmaniasis caused by the protozoan parasite Leishmania infantum is a chronic systemic disease endemic in Mediterranean basin. The aim of the study is to investigate the immune profile of dogs naturally infected by Leishmania infantum. In order to address such issue, CD4(+) and CD8(+) lymphocyte T cell subsets, peripheral CD4(+)CD3(+)Foxp3(+) (Treg) levels and the presence of pro-inflammatory T cells have been assessed, in 45 infected dogs and in 30 healthy animals, by using immunofluorescence and flow cytometry detection. Animals were categorised according to their clinical-pathological status and their antibody titer at diagnosis. Results showing a significant increase of CD8(+)CD3(+) T lymphocytes, a reduced percentage of the T regulatory CD4(+)CD3(+)Foxp3(+) subset and a significant increase of T(H)1 cells, characterise the infected dogs, regardless of their antibody titer or the occurrence of clinical symptomatic disease. These data may provide new insights into the pathogenesis of immune-mediated alterations associated with canine leishmaniasis.

Study of peripheral blood cell populations involved in the immune response of goats naturally infected with Mycobacterium caprae.

Tuberculosis in goats caused by Mycobacterium bovis and Mycobacterium caprae has noteworthy sanitary and economic implications. Current diagnostic assays are based on cellular immunity and although they have demonstrated a high sensitivity, some animals remain undetected. In the present study, flow cytometry has been used to determine changes in CD4+, CD8+ and CD25+ T cell populations in peripheral blood from naturally infected goats. Proportion of lymphocytes producing PPD-specific interferon-gamma (IFN-γ) was calculated and an ELISA for detection of PPD-specific IFN-γ was performed to measure the cytokine in plasma. The infected goats showed percentages of CD4+ T cells between 27.31% and 47.23% and there were not significant differences (p=0.113) with the non-infected control goats although the mean percentage was lower in this group. Regarding CD8+ T cells, a higher percentage was observed in healthy goats compared to controls (p=0.081). The mean percentage of lymphocytes expressing CD25 without antigen stimulation (30.65±3.91) was higher in lesion and/or culture-positive animals than in the controls (21.84±1.21; p=0.053). The percentage of CD4+/IFN+ T cell population stimulated with bovine PPD was a reliable marker of infection, since the mean percentage in the infected goats was significantly higher than in the controls (p<0.05). Tuberculosis in goats caused by M. caprae induced changes in cellular populations similar to those described for M. bovis in cattle.

Effects of Saccharomyces cerevisiae extract on haematological parameters, immune function and the antioxidant defence system in breeder hens fed aflatoxin contaminated diets.

The study was conducted to investigate the efficacy of Saccharomyces cerevisiae extract (SC) on haematological parameters, immune function, and the antioxidant defence system in breeder hens fed a diet contaminated with low level aflatoxin (AF). Forty-eight Ross 308 breeder hens were fed on diets containing AF (0 or 100 µg/kg) and SC (0 or 1 g/kg) in a 2 × 2 factorial arrangement. Red blood cell (RBC), white blood cell (WBC), and platelet counts, differential leucocyte counts, blood CD3+, CD4+, CD8+ and CD5+ T cell ratios, phagocytic activity and oxidative burst of heterophils, plasma and liver catalase activity, and malondialdehyde (MDA) and ascorbic acid concentrations were measured. 3. Plasma and liver MDA concentrations increased (P < 0·05), liver catalase activity decreased (P < 0·05) and total WBC count tended to decrease (P = 0·082) in hens fed the contaminated diet. WBC count, monocyte percentage, phagocytic activity and oxidative burst of heterophils increased (P < 0·05), and plasma MDA concentration tended to decrease (P = 0.088) in SC extract supplemented hens. There was a significant interaction between AF and SC on heterophil, lymphocyte, CD5+ cell percentages, and plasma catalase activity. Blood heterophil percentage decreased but lymphocyte percentage increased in hens fed on the AF contaminated diet without SC supplementation. SC supplementation counteracted the negative effect of AF on heterophils and lymphocytes. The CD5+ cell percentage decreased in unsupplemented hens fed the AF contaminated diet and this negative effect was minimised in SC supplemented hens. Plasma catalase activity increased in SC supplemented hens fed the uncontaminated diet whereas the effect of SC decreased in hens fed the AF contaminated diet. 4. The SC reduced some of the some adverse effects of AF, and improved functions of the non-specific immune system. Therefore, the SC extract which has been used for improving productive performance in birds and mammals may also be useful for modulating some of the effects of a low level, chronic dosage of AF.

Molecularly cloned SHIV-CN97001: a replication-competent, R5 simian/human immunodeficiency virus containing env of a primary Chinese HIV-1 clade C isolate.

BACKGROUND: The increasing prevalence of human immunodeficiency virus type 1 (HIV-1) subtype C infection worldwide calls for efforts to develop a relevant animal model for evaluating AIDS candidate vaccines. In China, the prevalent HIV strains comprise a circulating recombinant form, BC (CRF07_BC), in which the envelope belongs to subtype C. METHODS: To evaluate potential AIDS vaccines targeting Chinese viral strains in non-human primate models, we constructed a simian/human immunodeficiency virus (SHIV) carrying most of the envelope sequence of a primary HIV-1 clade C strain isolated from an HIV-positive intravenous drug user from YunNan province in China. Furthermore, to determine whether in vivo adaptation would enhance the infectivity of SHIV-CN97001, the parental infectious strain was serially passaged through eight Chinese rhesus macaques. RESULTS: Infection of six Chinese rhesus macaques with SHIV-CN97001 resulted in a low level of viremia and no significant alteration in CD4+ T-lymphocyte counts. However, the hallmarks of SHIV infectivity developed gradually, as shown by the increasingly elevated peak viremia with each passage. CONCLUSION: These findings establish that the R5-tropic SHIV-CN97001/Chinese rhesus macaque model should be very useful for the evaluation of HIV-1 subtype C vaccines in China.

Increased inherent intestinal granzyme B expression may be associated with SIV pathogenesis in Asian non-human primates.

BACKGROUND: Unlike Asian non-human primates, chronically SIV-infected African non-human primates (NHP) display a non-pathogenic disease course. The different outcomes may be related to the development of an SIV-mediated breach of the intestinal mucosa in the Asian species that is absent in the African animals. METHODS: To examine possible mechanisms that could lead to the gut breach, we determined whether the colonic lamina propria (LP) of SIV-naïve Asian monkeys contained more granzyme B (GrB) producing CD4 T cells than did that of the African species. GrB is a serine protease that may disrupt mucosal integrity by damaging tight junction proteins. RESULTS: We found that the colonic LP of Asian NHP contain more CD4(+) /GrB(+) cells than African NHP. We also observed reduced CD4 expression on LP T cells in African green monkeys. CONCLUSION: Both phenotypic differences could protect against SIV-mediated damage to the intestinal mucosa and could lead to future therapies in HIV(+) humans.

Relationship between cortisol response to stress and behavior, immune profile, and production performance of dairy ewes.

The existence of a relationship between cortisol levels, after an acute stress, and behavioral activities, immunological profile, and production performance in sheep was studied. An initial flock of 30 Comisana ewes was involved in the experiment, and each of the 30 ewes was individually subjected to an isolation test in a novel environment. Subsequently, from the initial flock, 2 groups of 8 Comisana ewes were each retrospectively selected, and the animals were divided, according to their cortisol concentration 10 min after the isolation test, into high cortisol (HC) ewes, having a peak of cortisol concentration >90 ng/mL (average: 119.3 ng/mL +/- 11.8), and low cortisol (LC) ewes having a peak of cortisol concentration <80 ng/mL (average: 52.4+/-11.8). During the isolation test, the behavior of each animal was video-recorded and behavioral activities were registered. Blood samples were collected before the isolation test, immediately after the test (10 min), and at 60, 120, 300 min, 24 h, and 48 h after the test to evaluate percentages of T-helper (CD4(+)) and T-cytotoxic (CD8(+)) cells, CD4(+)/CD8(+) ratio, and IL-1beta and IL-6 levels. The ewes were milked for 3 d after the isolation test to determine cortisol levels and IL-1beta and IL-6 concentrations in whey. Milk yield was recorded at each milking, and milk samples were analyzed for pH, nutritional parameters, renneting properties, and somatic cell count. During the isolation test, HC ewes exhibited a shorter duration of movement and fewer bleats than LC ewes. The average plasma IL-1beta concentration was higher in HC than in LC ewes. The average whey IL-1beta and IL-6 concentrations were higher in whey from HC ewes than in LC ewes. A positive correlation emerged between plasma and whey IL-1beta concentrations. The average CD4(+)/CD8(+) ratio in blood was lower in HC than in LC ewes. Time from isolation affected the CD4(+)/CD8(+) ratio: at 120 min, the CD4(+)/CD8(+) ratio increased compared with that at 10 min after isolation and then decreased until 300 min after isolation. On average, ewes with low cortisol concentrations showed higher milk production and lower SCC than ewes with high cortisol concentrations. Results suggest that plasma cortisol concentration is connected to the behavioral response and immune competence of dairy ewes and cytokine concentrations. Both whey IL-1beta and IL-6 can be considered reliable indicators of the magnitude of hypothalamic-pituitary-adrenal axis activation. The stress-induced changes in CD4(+)/CD8(+) ratio are critical for controlling disease incidence and planning appropriate vaccination programs. High reactivity of the hypothalamic-pituitary-adrenal axis is also associated with a reduction in milk production and an increased predisposition to develop intramammary inflammatory processes.

Determination of CD4+ and CD8+ T cells in the peripheral blood of dogs with leishmaniosis before and after prolonged allopurinol monotherapy.

Canine leishmaniosis (CL) is a common systemic parasitic disease that is endemic in many Mediterranean countries including Greece. The immune reaction to the parasite is critical to the outcome of the infection and the response to treatment. Some studies have shown a reduction of circulating CD4+ T cells and of the CD4+/CD8+ ratio in dogs with CL and these changes normalised following treatment with meglumine antimoniate or amphotericin B. Allopurinol is used as a monotherapy for the chronic treatment of CL. The aim of the present study was to determine the circulating CD4+ and CD8+ T lymphocyte numbers and the CD4+/CD8+ ratio in 19 dogs diagnosed with CL before and after prolonged allopurinol monotherapy (18 months). A significant decrease in circulating CD4+ T cells was observed in dogs with CL before treatment. Prolonged allopurinol monotherapy improved the number of circulating CD4+ T cells, but did not restore their number to within the normal range.