Fungal infection control by garlic extracts (Allium sativum L) and modulation of peritoneal macrophages activity in murine model of sporotrichosis / Controle da infecção fúngica pelos extratos de alho (Allium sativum L) e modulação da atividade de macrófagos peritoneais em modelo murino de esporotricose

Abstract Garlic (Allium sativum L.) is grown all over the world as seasoning and medicinal vegetable since 3,000 BC. Allicin is the main component of garlic, being attributed to it the most of its biological activities, such as bactericidal, antifungal and antiviral actions. However, other compounds of garlic present antioxidant, hypocholesterolemic, vasodilator activities, protective action against different types of cancer, and immunomodulatory. Fungal infections are important causes of morbidity and mortality in people mainly in immunosuppressed ones. Sporothrix schenckii, the causing agent of Sporotrichosis (most common subcutaneous mycosis in Latin America), is dimorphic fungus, of saprophytic life in soil or plants, infecting people and animals mainly through skin injuries and bruises. The main of this work was to evaluate the influence of garlic consuming on immune modulation of healthy and infected Swiss mice in induced way by S. schenckii, since these animals functioning of peritoneal macrophages as well as the nitric oxide and cytokines' production (IL-1β, IL-10 and IL-12) and to evaluate the antifungal potential of garlic with S. schenckii through minimum inhibitory concentration test and colony-forming units. The results showed that garlic offers antifungal potential with S. schenckii. The oral taking of garlic extracts influences the releasing of cytokines by macrophages, regular consuming shows anti-inflammatory effect, and its acute use may take to an inflammatory response. Mice that consumed garlic responded more effectively to fight against the infection.

Resumo O alho (Allium sativum L.) é cultivado em todo o mundo como hortaliça condimentar e medicinal desde 3.000 a. C. A alicina é o principal componente do alho, sendo atribuída a ela a maior parte das suas atividades biológicas, dentre elas as ações bactericida, antifúngica e antiviral. Porém, outros compostos do alho apresentam atividade antioxidante, hipocolesterolemiante, vasodilatadora, ação protetora contra diversos tipos de câncer e imunomoduladora. As infecções por fungos são causas importantes de morbidade e mortalidade no homem principalmente em indivíduos imunossuprimidos. O Sporothrix schenckii, agente causal da esporotricose (micose subcutânea mais comum na América Latina), é fungo dimórfico, de vida saprofítica no solo ou em vegetais, infectando homens e os animais principalmente através de lesões e arranhões na pele. O objetivo desse trabalho foi avaliar a influência do consumo de alho na imunomodulação de camundongos Swiss saudáveis e infectados de forma induzida por S. schenckii, a partir do estado funcional dos macrófagos peritoneais desses animais quanto à produção de óxido nítrico e das citocinas (IL-1β, IL-10 e IL-12) e avaliar o potencial antifúngico do alho frente ao S. schenckii por meio de teste de concentração inibitória mínima e unidades formadoras de colônia. Os resultados demonstraram que o alho apresenta potencial antifúngico frente S. schenckii. A administração oral de extratos de alho influencia a liberação de citocinas por macrófagos, o consumo regular apresenta efeito anti-inflamatório, e seu uso agudo pode gerar uma resposta inflamatória. Camundongos que consumiram alho responderam de forma mais efetiva no combate da infecção.

MyD88-BLT2-dependent cascade contributes to LPS-induced interleukin-6 production in mouse macrophage

Endotoxic responses to bacterial lipopolysaccharide (LPS) are triggered by Toll-like receptor 4 (TLR4) and involve the production of inflammatory mediators, including interleukin-6 (IL-6), by macrophages. The detailed mechanism of IL-6 production by macrophages in response to LPS has remained unclear, however. We now show that LPS induces IL-6 synthesis in mouse peritoneal macrophages via the leukotriene B4 receptor BLT2. Our results suggest that TLR4-MyD88 signaling functions upstream of BLT2 and that the generation of reactive oxygen species (ROS) by NADPH oxidase 1 (Nox1) and consequent activation of the transcription factor nuclear factor (NF)-kappaB function downstream of BLT2 in this response. These results suggest that a TLR4-MyD88-BLT2-Nox1-ROS-NF-kappaB pathway contributes to the synthesis of IL-6 in LPS-stimulated mouse macrophages.

Sympathetic glial cells and macrophages develop different responses to Trypanosoma cruzi infection or lipopolysaccharide stimulation

Nitric oxide (NO) participates in neuronal lesions in the digestive form of Chagas disease and the proximity of parasitised glial cells and neurons in damaged myenteric ganglia is a frequent finding. Glial cells have crucial roles in many neuropathological situations and are potential sources of NO. Here, we investigate peripheral glial cell response to Trypanosoma cruzi infection to clarify the role of these cells in the neuronal lesion pathogenesis of Chagas disease. We used primary glial cell cultures from superior cervical ganglion to investigate cell activation and NO production after T. cruzi infection or lipopolysaccharide (LPS) exposure in comparison to peritoneal macrophages. T. cruzi infection was greater in glial cells, despite similar levels of NO production in both cell types. Glial cells responded similarly to T. cruzi and LPS, but were less responsive to LPS than macrophages were. Our observations contribute to the understanding of Chagas disease pathogenesis, as based on the high susceptibility of autonomic glial cells to T. cruzi infection with subsequent NO production. Moreover, our findings will facilitate future research into the immune responses and activation mechanisms of peripheral glial cells, which are important for understanding the paradoxical responses of this cell type in neuronal lesions and neuroprotection.

Nitric oxide production by Peromyscus yucatanicus (Rodentia) infected with Leishmania (Leishmania) mexicana

Peromyscus yucatanicus (Rodentia: Cricetidae) is a primary reservoir of Leishmania (Leishmania) mexicana (Kinetoplastida: Trypanosomatidae). Nitric oxide (NO) generally plays a crucial role in the containment and elimination of Leishmania. The aim of this study was to determine the amount of NO produced by P. yucatanicus infected with L. (L.) mexicana. Subclinical and clinical infections were established in P. yucatanicus through inoculation with 1 x 10 2 and 2.5 x 10 6 promastigotes, respectively. Peritoneal macrophages were cultured alone or co-cultured with lymphocytes with or without soluble Leishmania antigen. The level of NO production was determined using the Griess reaction. The amount of NO produced was significantly higher (p ≤ 0.0001) in co-cultured macrophages and lymphocytes than in macrophages cultured alone. No differences in NO production were found between P. yucatanicus with subclinical L. (L.) mexicana infections and animals with clinical infections. These results support the hypothesis that the immunological mechanisms of NO production in P. yucatanicus are similar to those described in mouse models of leishmaniasis and, despite NO production, P. yucatanicus is unable to clear the parasite infection.

Production of TNF-α, nitric oxide and hydrogen peroxide by macrophages from mice with paracoccidioidomycosis that were fed a linseed oil-enriched diet

Omega-3 polyunsaturated fatty acids (n-3 PUFA) can modulate the immune system and their primary effect is on macrophage function. Paracoccidioidomycosis (PCM) is an endemic systemic mycosis in Latin America that is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). Macrophages are the main defence against this pathogen and have microbicidal activity that is dependent on interferon-Γ and tumour necrosis factor (TNF)-α. These cytokines stimulate the synthesis of nitric oxide (NO) and hydrogen peroxide (H2O2), leading to the death of the fungus. To study the effect of n-3 PUFA on the host immune response during experimental PCM, macrophages that were obtained from animals infected with Pb18 and fed a diet enriched by linseed (LIN) oil were cultured and challenged with the fungus in vitro. The macrophage function was analysed based on the concentrations of TNF-α, NO and H2O2. LIN oil seems to influence the production of TNF-α during the development of disease. A diet enriched with LIN oil influences the microbicidal activity of the macrophages by inducing the production of cytokines and metabolites such as NO and H2O2, predominantly in the chronic phase of infection.

Kinetoplastid membrane protein-11 exacerbates infection with Leishmania amazonensis in murine macrophages

In Leishmania amazonensis, kinetoplastid membrane protein-11 (KMP-11) expression increases during metacyclogenesis and is higher in amastigotes than in promastigotes, suggesting a role for this protein in the infection of the mammalian host. We show that the addition of KMP-11 exacerbates L. amazonensis infection in peritoneal macrophages from BALB/c mice by increasing interleukin (IL)-10 secretion and arginase activity while reducing nitric oxide (NO) production. The doses of KMP-11, the IL-10 levels and the intracellular amastigote loads were strongly, positively and significantly correlated. The increase in parasite load induced by KMP-11 was inhibited by anti-KMP-11 or anti-IL-10 neutralising antibodies, but not by isotype controls. The neutralising antibodies, but not the isotype controls, were also able to significantly decrease the parasite load in macrophages cultured without the addition of KMP-11, demonstrating that KMP-11-induced exacerbation of the infection is not dependent on the addition of exogenous KMP-11 and that the protein naturally expressed by the parasite is able to promote it. In this study, the exacerbating effect of KMP-11 on macrophage infection with Leishmania is for the first time demonstrated, implicating it as a virulence factor in L. amazonensis. The stimulation of IL-10 production and arginase activity and the inhibition of NO synthesis are likely involved in this effect.

Efecto inmunosupresor de Trypanosoma lewisi (Kinetoplastidae) sobre la multiplicación de Toxoplasma gondii (Sarcocystidae) en macrófagos alveolares y peritoneales de rata blanca

The immunosuppressant effect of T. lewisi (Kinetoplastidae) infection on the multiplication of Toxoplasma gondii (Sarcocystidae) on alveolar and peritoneal macrophages of the white rat. The immunosuppressant effect of T. lewisi infection on the multiplication of T. gondii was compared in peritoneal (MP) and alveolar macrophages (MA) of white rat. Two animal groups were infected with T. lewisi and sacrificed after four days and seven days post infection. A group without infection was maintained as a control. The number of intracellular parasites (tachyzoites) (IT) was counted by light microscopy, calculating the rate infection rate per 100 total cells (TC) and per infected cells (IC) for each group of phagocyte cells. The relation quotient IT, TC or IC multiplied percent, provided a statistical ratio (RE) of the relative number of parasites in both cellular types for each time interval. MA as well as MP obtained after 4 days showed a significant increase in the multiplication of T. gondii with respect to the control. Unlike the MP (which had an increase in the multiplication of T. gondii the fourth day of infection with T. lewisi diminishing towards the seventh day), the MA had an increase in the multiplication of the parasite from the fourth to the seventh day. This difference can be related to the route of infection used for the experiments, that affect the MP directly with a greater effect in comparison with the MA of the lungs. Lung compartment will be affected later, when the infection becomes systemic between the fourth and sixth day of infection. The immunity against T. gondii is similar between both phagocytes, but the time of infection and the compartment where the cells are located, makes the difference in the response time against T. gondii. Supernatants from macrophage cultures or T. lewisi by rat did not induced any immunosuppression. Rev. Biol. Trop. 57 (1-2): 13-22. Epub 2009 June 30.

El efecto inmunosupresor de la infección de T. lewisi sobre la multiplicación de T. gondii fue comparado en macrófagos peritoneales (MP) y alveolares (MA) de rata. El número de parásitos (taquizoitos) intracelulares (TI) fue contado por microscopía de luz. Los macrófagos alveolares y peritoneales (MP) de animales con 4 días de infección con T. lewisi muestran un aumento significativo en la multiplicación de T. gondii. A diferencia de los MP (que muestran un aumento en la multiplicación de T. gondii al cuarto día de infección con T. lewisi disminuyendo hacia el séptimo día), los MA mantienen un aumento en la multiplicación del parásito desde el cuarto, aumentando hacia el séptimo día de infección. Esta diferencia se puede deber a la ruta de infección utilizada para los experimentos que afectan directamente los MP donde se observa un efecto mayor y más temprano en comparación con los MA aislados de los pulmones, compartimiento afectado cuando la infección se vuelve sistémica entre el cuarto y sexto día de infección. La inmunidad contra T. gondii es similar entre ambas células fagocíticas, pero el tiempo de infección y el compartimiento donde se encuentren las células hace la diferencia en el tiempo de respuesta contra un parásito dado, en nuestro caso T. gondii. No hubo evidencia de que los sobrenadantes de cultivos de macrófagos provenientes de ratas infectadas ni el lisado de tripanosomas indujeran el efecto inmunosupresor.

Cytokine and nitric oxide production by mouse macrophages infected with Brazilian flaviviruses / Produção de citocinas e óxido nítrico por macrófagos de camundongos infectados com flavivírus brasileiros

The Flaviviridae family, Flavivirus genus includes viruses that are transmitted to vertebrates by infected mosquitoes or ticks. The genus Flavivirus includes a variety of viruses that cause diseases such as acute febrile illness, encephalitis, and hemorrhagic fever. Flaviviruses primarily infect blood monocytes and tissue macrophages, which have been shown to be permissive, supporting viral replication and serving as virus reservoirs. On the other hand, these cells may have an important antiviral activity related to modulation by cytokine production and by the capacity of these cells to synthesize reactive free radicals such as nitric oxide (NO) which can have a microbicidal effect. The present study was performed in order to determine the production of cytokines interleukin-1beta (IL-1β), tumor necrosis factor -alpha (TNF-α), transforming growth factor- beta (TGF-β) and interferon -alpha (IFN-α) and NO by macrophages infected with one of four Brazilian flaviviruses, Bussuquara virus (BUSV), Yellow Fever virus (YFV), Rocio virus (ROCV) and Encephalitis Saint Louis virus (SLEV), and to verify the possible antiviral effect of NO during macrophage infection with ROCV. Moreover, we asked if the different viruses were able to regulate bacterial lipopolysaccharide (LPS) induced cytokine production. Our results showed that YFV and SLEV reduced the production of IL-1β and TGF-β by LPS-stimulated macrophages, while ROCV only diminished LPS-stimulated TGF-β synthesis. On the other hand, BUSV more likely favored an enhancement of the LPS-induced production of IL-1β by macrophages. Additionally, while most of the viruses stimulated the production of IFN-α, none of them altered the production of TNF-α by murine macrophages. Interestingly, all viruses induced synthesis of NO that was not correlated with antiviral activity for ROCV.

A família Flaviviridae, gênero flavivírus inclui vírus que são transmitidos para os vertebrados por mosquitos e carrapatos. O gênero flavivirus inclui uma variedade de vírus que causa doenças como febres, encefalites e febres hemorrágicas. Primeiramente, as flaviviroses infectam monócitos do sangue e macrófagos do tecido, o qual tem mostrado ser permissivo, suportando a replicação viral e servindo como reservatório de vírus. Por outro lado, essas células podem ter uma importante atividade antiviral relacionada à modulação pela produção de citocinas e pela capacidade destas células sintetizar reativos de radicais livres como óxido nítrico (NO) o qual tem efeito microbicida. O presente estudo foi realizado a fim de determinar a produção de citocinas interleucina -1 beta (IL-1β), fator de necrose tumoral-alfa (TNF-α), fator de crescimento transformador-beta (TGF-β), interferon - alfa (IFN-α) e NO pelos macrófagos infectados com os quatros flavivírus como vírus Bussuquara (BUSV), vírus da febre amarela (YFV), vírus Rocio (ROCV) e vírus da Encefalite de Saint Louis (SLEV), e verificar o possível efeito antiviral de NO durante a infecção dos macrófagos com ROCV. Além disso, com os diferentes vírus foram capazes de regular o lipopolissacarídeo bacteriano (LPS) indutor da produção de citocinas. Nossos resultados mostraram que YFV e SLEV reduziram a produção de IL-1β e TGF-β quando macrófagos foram estimulados pelo LPS, enquanto ROCV somente diminuiu a síntese de TGF-β estimulada pelo LPS. Entretanto, BUSV favoreceu uma acentuada produção de IL-1β pelos macrófagos estimulados pelo LPS, enquanto os vírus estimularam a produção de IFN-α, nenhum deles alterou a produção de TNF-α pelos macrófagos murinos. Interessantemente, todos os vírus induziram a síntese de NO que não esteve correlacionada com a atividade antiviral pelo ROCV.

Lactobacillus delbrueckii UFV-H2b20 induces type 1 cytokine production by mouse cells in vitro and in vivo

Lactobacillus delbrueckii UFV-H2b20 has been shown to increase clearance of bacteria injected into the blood of germ-free mice. Moreover, it induces the production of type 1 cytokines by human peripheral mononuclear cells. The objective of the present study was to investigate the production of inflammatory cytokines [interleukin-12 (IL-12 p40), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ)] triggered in vitro by live, heat-killed or lysozyme-treated L. delbrueckii UFV-H2b20 and in vivo by a live preparation. Germ-free, L. delbrueckii-monoassociated and lipopolysaccharide (LPS)-resistant C3H/HeJ mice were used as experimental models. UFV-H2b20 induced the production of IL-12 p40 and TNF-α by peritoneal cells and IFN-γ by spleen cells from germ-free or monoassociated Swiss/NIH mice and LPS-hyporesponsive mice (around 40 ng/mL for IL-12 p40, 200 pg/mL for TNF-α and 10 ng/mL for IFN-γ). Heat treatment of L. delbrueckii did not affect the production of these cytokines. Lysozyme treatment decreased IL-12 p40 production by peritoneal cells from C3H/HeJ mice, but did not affect TNF-α production by these cells or IFN-γ production by spleen cells from the same mouse strain. TNF-α production by peritoneal cells from Swiss/NIH L. delbrueckii-monoassociated mice was inhibited by lysozyme treatment. When testing IL-12 p40 and IFN-γ levels in sera from germ-free or monoassociated Swiss/NIH mice systemically challenged with Escherichia coli we observed that IL-12 p40 was produced at marginally higher levels by monoassociated mice than by germ-free mice (40 vs 60 ng/mL), but IFN-γ was produced earlier and at higher levels by monoassociated mice (monoassociated 4 and 14 ng/mL 4 and 8 h after infection, germfree 0 and 7.5 ng/mL at the same times). These results show that L. delbrueckii UFV-H2b20 stimulates the production of type 1 cytokines in vitro and in vivo, therefore suggesting...

Revisitando a cavidade peritoneal de camundongos: identificação de novos subtipos funcionais de linfócitos B-1 e macrófagos / Revisiting the mouse peritoneal cavity: identification of new functionally distinct subsets of macrophages and B-1 lymphocytes

A cavidade peritoneal de camundongos abriga uma variedade de células do sistema imune. Inicialmente, devido as limitações metodológicas, acreditava-se que, aproximadamente, 90% das células peritoneais era representada por macrófagos. Em seguida, graças aos extensos estudos com células peritoneais, observou-se que, além dos macrófagos, o peritônio abrigava muitos Linfócitos B, principalmente do subtipo B-1. Utilizando metodologias contemporâneas de FACS - citometria de fluxo, este trabalho mostra que, aproximadamente, 30% das células peritoneais são macrófagos, 55% são Iinfócitos B-1, dos quais 40% pertencem ao subtipo B-1a e 15% ao subtipo B-1b. Os 15% - 20% restantes representam outros subtipos celulares, como linfócitos T, linfócitos B-2, linfócitos NK, eosinófilos, além da presença de outras populações de células que não foram possíveis de ser identificadas com os marcadores de superfície utilizados neste trabalho. Em contraste com a literatura, nossos estudos mostraram que os macrófagos da cavidade peritoneal de camundongos representam uma população heterogênea...

Polysaccharide-rich fraction of Agaricus brasiliensis enhances the candidacidal activity of murine macrophages

A polysaccharide-rich fraction (ATF) of medicinal mushroom Agaricus brasiliensis was evaluated on the candidacidal activity, H2O2 and nitric oxide (NO) production, and expression of mannose receptors by murine peritoneal macrophages. Mice received three intraperitoneal (i.p.) injections of ATF and after 48 h their peritoneal resident macrophages were assayed against Candida albicans yeast forms. The treatment increased fungicidal activity and it was associated with higher levels of H2O2, whereas NO production was not affected. We also found that the treatment enhances mannose receptor expression by peritoneal macrophages, which are involved in the attachment and phagocytosis of non-opsonized microorganisms. Treatment of animals with ATF was able to enhance the clearance of C. albicans during the first 6 h after the experimental i.p. infection. Our results suggest that this extract can increase host resistance against some infectious agents through the stimulation of microbicidal activity of macrophages.

Anti-tumor immunostimulatory effect of heat-killed tumor cells

As a part of our ongoing search for a safe and efficient anti-tumor vaccine, we attempted to determine whether the molecular nature of certain tumor antigens would influence immune responses against tumor cells. As compared with freeze-thawed or formaldehyde-fixed tumor antigens, heat-denatured tumor antigens elicited profound anti-tumor immune responses and greatly inhibited the growth of live tumor cells. The heat-denatured tumor antigens induced a substantial increase in the anti-tumor CTL response in the absence of any adjuvant material. This response appears to be initiated by strong activation of the antigen-presenting cells, which may recognize heat-denatured protein antigens. Upon recognition of the heat-denatured tumor antigens, macrophages and dendritic cells were found to acutely upregulate the expression of co-stimulatory molecules such as B7.2, as well as the secretion of inflammatory cytokines such as IL-12 and TNF-alpha. The results of this study indicate that heat-denatured tumor extracts might elicit protective anti-tumor adaptive immune responses and also raise the possibility that a safe and efficient adjuvant-free tumor vaccine might be developed in conjunction with a dendritic cell-based tumor vaccine.

Influences of DTC and zinc supplementation on the cellular response restoration in restrained mice

The studies were conducted on Balb/c mice exposed to restraint stress twice for 12 h at 24 h intervals. Prior to restraint stress the mice were treated with sodium diethyldithiocarbamate (DTC) i.p. at a dose of 20 mg/kg five times at 48 h intervals. DTC was used per se or with zinc ions interaction, by adding zinc sulfate to drinking water at a dose of 72 microgram/mouse daily. The results obtained in the study show that restraint stress causes involution of lymphatic organs, decreased the percentage of immature (CD4+CD8+) and, mature (CD4+) thymocytes and CD4+, CD8+and CD19 + splenocytes and proliferative response of thymocytes stimulated in vitro with concanavalin A (Con A) and phytohemagglutinin (PHA). The restraint stress decreased also interleukin-1 (IL-1) production by murine intraperitoneal macrophages stimulated in vitro with lipopolysaccharide (LPS) from E. coli. Pretreatment with DTC counteracted restraint stress-induced immunosuppression, which is expressed as partial normalisation of the total number of thymocytes, splenocytes and IL-1 production, accelerated regeneration of thymus and spleen, shorter suppressive action of restraint stress on the percentage of CD4+CD8+thymocytes and in total normalisation of the CD4+thymocytes and splenocytes. DTC administered prior to restraint stress augmented the proliferative response of thymocytes to two mitogens. The immunocorrecting action of DTC is enhanced by zinc supplementation, expressed in the increased percentage of CD4+thymocytes and splenocytes, CD19 + splenocytes, proliferative activity of thymocytes stimulated with PHA and IL-1 production. The obtained results show that DTC administration can be supplemented with zinc in order to restore the immune system impaired by stress.

Effect of trypanosoma lewisi infection on the toxoplasma gondii multiplication in white rat peritoneal macrophages

Peritoneal macrophages (PM) from normal Wistar rats were treated in vitro with peritoneal supernatant or sera, obtained from rats infected with 106 Trypanosoma lewisi trypomastigotes before the infection with Toxoplasma gondii tachyzoites. In this experimental model, Toxoplasma multiplication in PM was increased, as compared to macrophages treated with supernatant or sera from control rats not infected with T. lewisi. This effect was observed only if the active supernatant or sera came from rats infected with the T. lewisi 3 to 6 d before Toxoplasma inoculation. Furthermore, immunosuppressive activity was only detectable after at least 24 h incubation with the supernatant or sera. These results are in accordance with our in vivo previous studies which demonstrated a clear immunosuppressive effect of T. lewisi during T.gondii infection of the remarkably resistant Wistar rats.

Early effect of Mycobacterium tuberculosis infection on Mac-1 and ICAM-1 expression on mouse peritoneal macrophages

Effect of M. tuberculosis infection was studied on the expression of intercellular adhesion molocule-1 (ICAM-1) and Mac-1 markers on murine peritoneal macrophages. Intraperitoneal administration of M. tuberculosis resulted in a marked increase in the proportion of Mac-1+ cells whereas the proportion of ICAM-1+ cells declined sharply 4 h post infection. Absolute numbers of Mac-1+ and ICAM-1+ cells however increased at all time points after the infection. Comparison of kinetics of changes observed in Mac-1+ and ICAM-1+ cell populations with differential leukocyte counts in peritoneal cells indicated that these alterations could be due to cellular influx, especially that of neutrophils, or up regulation of these markers on macrophages and other peritoneal cells. In adherent peritoneal macrophages infected in vitro with M. tuberculosis, proportion of Mac-1+ and ICAM-1+ cells increased markedly within 24 h of infection. Mean expression of these markers on per cell basis also increased significantly. Similar results were obtained by using RAW 264.7 mouse macrophage cell line, suggesting that the enhanced expression of Mac-1 and ICAM-1 markers was a direct effect of M. tuberculosis infection and not mediated by contaminating cell types present in adherent macrophage preparations. Mac- 1 and ICAM-1 expression was further studied on macrophages that had actually engulfed M. tuberculosis and compared with bystander macrophages without intracellular M. tuberculosis. For this purpose M. tuberculosis pre-stained with DilC18 fluorescent dye were used for infecting adherent peritoneal macrophages. Mac-1 and ICAM-1 expression on gated DilC18 positive and negative cell populations was analyzed. Our results indicate that the expression of Mac-1 and ICAM- 1 markers was significantly enhanced on all macrophages incubated with M. tuberculosis but was more pronounced on macrophages with internalized mycobacteria. Taken together, our results suggest that the expression of Mac-1 and ICAM-1 markers is significantly up regulated

Desnutrição protéica: efeito sobre o espraiamento, fagocitose e atividade fungicida de macrófagos peritoneais / Protein malnutrition: effect on spreading phagocytosis and fungicide activity of peritoneal macrophages

A desnutrição protéico-calórica modifica tanto a resposta imune específica como a inespecífica, predispondo o indivíduo a agentes infecciosos. Neste trabalho avaliamos o efeito da desnutrição protéica sobre o espraiamento, fagocitose e a atividade fungicida de macrófagos peritoneais frente à Candida albicans. Camundongos Swiss, adultos, machos foram divididos em dois grupos: nutrido (controle), alimentado com ração contendo 20 porcento de proteína e grupo desnutrido, que recebeu ração com 4 porcento de proteína. Os macrófagos peritoneais foram ativados por meio da administração intraperitonial de caseinato de sódio 3 porcento. Observamos que macrófagos residentes oriundos de animais desnutridos...

Augmentation of non-specific immunity in mice by gold preparations used in traditional systems of medicine.

BACKGROUND & OBJECTIVES: Gold preparations are highly valued in Indian systems of medicine and extensively used for tonic and rejuvenating properties. This study was aimed to evaluate the effects of Ayurvedic gold preparation Swarna Bhasma (SB) and Unani preparation Kushta Tila Kalan (KTK) on non-specific immunity in mice. A gold-containing drug auranofin (AN) used in modern medicine was studied for comparison. METHODS: Male mice were administered with the incremental doses of these drugs orally for 10 days. Parameters of study included body weight, organ weight, peritoneal exudate cell (PEC) counts and phagocytic activity of PEC. RESULTS: Both test drugs (KTK and SB) significantly (P < 0.001) increased counts of peritoneal macrophages and stimulated phagocytic index of macrophages. AN elicited a suppressive action on these parameters. INTERPRETATION & CONCLUSION: Traditional preparations of gold exhibited immunostimulant activity on macrophage functions in contrast to immunosuppressive effects of AN. This is an interesting observation and gives a rational basis to the claims of efficacy and safety of gold when used in calcined forms.

Protein-calorie malnutrition: decrease in the peritonial macrophage's respiratory burst

Protein malnutrition and disease are frequently associated. It modifies both the organism's specific and non-specific immune response to infectious agents. However, the exact mechanisms underlying these findings have not yet been clearly elucidated. In this study, we examined the respiratoy burst capacity in resident and activated peritoneal macrophages obtained from adult male mice who were fed either a control (20 porcent protein) or a low-protein (4 porcent protein) diet. The activated macrophages were obtained after an intra-peritoneal administration of sodium caseinate. Through chemiluminescence assays using either luminol or lucigenin, the kinetics and production...

Ensaio de adesão e detecção de RNA mensageiro de fibronectina em macrofágos peritoniais de camundongos submetidos à desnutrição proteíca experimental / Test of adhesion and detection of messenger RNA of mice peritoneal macrophages fibronectin submitted to experimental protein malnutrition

Muito dos mecanismos que comprometem o sistema imune em estados de desnutrição ainda estão para ser esclarecidos. O estado nutricional influencia na evolução de pacientes internados, na infância e em idosos. No nosso trabalho estudamos um modelo experimental de desnutrição proteíca, na qual fornecemos uma ração hipoproteíca para camundongos Swiss (4 porcento de proteina) para induzir a desnutrição protéica e estudar a função dos macrófagos peritoniais. Observamos alterações na adesividade, com expressão reduzida de fibronectina, uma molécula adesiva da matriz extracelular. No entanto o RNAm apresenta-se com tendência a apresentar valores maiores no desnutrido, o qual ao ser estimulado com...

Correlation and modulation of Ehrlich ascites tumor growth with tumor-plasma IgA.

Plasma IgA level of Ehrlich ascites tumor bearing mice showed correlation with progress of tumor growth. In PAGE analysis total plasma IgA separated into 3 major bands corresponding to mol. wt. > or = 669,000 daltons, identical to 443,000 daltons and between 443,000 and 150,000 daltons. All the three bands increased gradually with progress of tumor growth upto day 14 and then declined on day 16. Total plasma IgA isolated by anti-IgA affinity chromatography when adoptively transferred to mice inhibited tumor growth. Affinity-purified plasma IgA separated into three major peak fractions after Sephadex G-200 column chromatography which corresponded with the bands of IgA on PAGE analysis. Three Sephadex G-200 IgA fractions when adoptively transferred to tumor-bearing mice showed effect different from total IgA. High mol. wt. IgA fraction (> or = 669,000 daltons) inhibited tumor growth whereas medium mol. wt. fraction (identical to 443,000 daltons) enhanced tumor growth. The low mol. wt. IgA fraction (< 443,000 and > 150,000 daltons) had no significant effect on tumor growth. The high mol. wt. IgA fraction enhanced tumor killing ability of peripheral blood lymphocytes (PBL) and peritoneal macrophages of tumor bearer in vitro. Medium mol. wt. IgA fraction inhibited tumor-killing ability of PBL in vitro but had no significant effect on peritoneal macrophages. The low mol. wt. IgA fraction showed a mild enhancing effect on tumor-killing ability of PBL but had no significant effect on peritoneal macrophages. The results established importance of IgA in tumor growth regulation and its therapeutic potentiality. The results indicated that tumor growth modulation by tumor plasma IgA is also mediated by its effect on cellular anti-tumor immune factors of the host.