Comparative Assessment of E-cadherin's Expression between the Metastatic and Non-metastatic Oral Squamous Cell Carcinoma: An Immunohistochemical Study

ABSTRACT Objective: To identify the clinicopathological correlation of E-cadherin expression in metastatic and non-metastatic oral squamous cell carcinoma (OSCC). Material and Methods: A total of 90 paraffin-embedded tissue sections of OSCC were retrieved from the registry. The total selected samples were 45 cases each from the primary lesions of metastatic and non-metastatic OSCC. One section was subjected to routine Hematoxylin and eosin stain and another to immunohistochemical analysis for E-cadherin expression. Results: A non-significant (p˃0.05) increased expression is seen in the non-metastatic group compared to the metastatic group, with predominantly membrane as the staining site in either group. However, the expression of E-cadherin did not reveal any statistically significant association with independent variables such as age, gender, and adverse habits of the patients (p>0.05). On the other hand, with respect to the histological differentiation of OSCC, a significant association (p<0.001) was observed with the well-differentiated type of metastatic OSCC. Conclusion: E-cadherin was useful to some extent in predicting regional metastasis. However, further studies using a panel of biomarkers with increased sample size may help us understand the process involved in metastasis.

Antibody recognition of Plasmodium falciparum infected red blood cells by symptomatic and asymptomatic individuals in the Brazilian Amazon

In the Amazon Region, there is a virtual absence of severe malaria and few fatal cases of naturally occurring Plasmodium falciparum infections; this presents an intriguing and underexplored area of research. In addition to the rapid access of infected persons to effective treatment, one cause of this phenomenon might be the recognition of cytoadherent variant proteins on the infected red blood cell (IRBC) surface, including the var gene encoded P. falciparum erythrocyte membrane protein 1. In order to establish a link between cytoadherence, IRBC surface antibody recognition and the presence or absence of malaria symptoms, we phenotype-selected four Amazonian P. falciparum isolates and the laboratory strain 3D7 for their cytoadherence to CD36 and ICAM1 expressed on CHO cells. We then mapped the dominantly expressed var transcripts and tested whether antibodies from symptomatic or asymptomatic infections showed a differential recognition of the IRBC surface. As controls, the 3D7 lineages expressing severe disease-associated phenotypes were used. We showed that there was no profound difference between the frequency and intensity of antibody recognition of the IRBC-exposed P. falciparum proteins in symptomatic vs. asymptomatic infections. The 3D7 lineages, which expressed severe malaria-associated phenotypes, were strongly recognised by most, but not all plasmas, meaning that the recognition of these phenotypes is frequent in asymptomatic carriers, but is not necessarily a prerequisite to staying free of symptoms. .

Pregnancy malaria: cryptic disease, apparent solution

Malaria during pregnancy can be severe in non-immune women, but in areas of stable transmission, where women are semi-immune and often asymptomatic during infection, malaria is an insidious cause of disease and death for mothers and their offspring. Sequelae, such as severe anaemia and hypertension in the mother and low birth weight and infant mortality in the offspring, are often not recognised as consequences of infection. Pregnancy malaria, caused by Plasmodium falciparum, is mediated by infected erythrocytes (IEs) that bind to chondroitin sulphate A and are sequestered in the placenta. These parasites have a unique adhesion phenotype and distinct antigenicity, which indicates that novel targets may be required for development of an effective vaccine. Women become resistant to malaria as they acquire antibodies against placental IE, which leads to higher haemoglobin levels and heavier babies. Proteins exported from the placental parasites have been identified, including both variant and conserved antigens, and some of these are in preclinical development for vaccines. A vaccine that prevents P. falciparum malaria in pregnant mothers is feasible and would potentially save hundreds of thousands of lives each year.

Tratamento superficial de implantes e sua influência na adesão e viabilidade de células e bactérias: uma revisão / Surface treatment for implants and their influence on the accession and viability of cells and bacteria: a review

O tratamento superficial aplicado aos implantes de titânio tem como principal finalidade acelerar o processo de osseointegração. Inicialmente a única preocupação dos pesquisadores, era como o tratamento aplicado alterava a topografia superficial do titânio. Porém com o tempo, descobriu-se que no que diz respeito aos fatores biológicos, as características químicas influenciam mais que a topografia. Este trabalho teve como objetivo avaliar através de uma revisão da literatura científica, como as alterações dos implantes do titânio podem interferir no processo de adesão e proliferação, tanto de células quanto de bactérias. Alguns estudos demonstram que o tratamento superficial influencia nos primeiros estágios da osseointegração, porém não há um aumento no número de osteoblastos, mas sim uma alteração no padrão de adesão celular. E no que diz respeito aos fatores biológicos, as características químicas influenciam mais que as características topográficas tanto para células quanto para bactérias

The surface treatment applied to titanium implants whose main purpose is to accelerate the process of osseointegration. Initially the only concern of the researchers was how this processaltered the surface topography of titanium. But with time, it was discovered that biological andchemical characteristics influence topography the most. This study aimed to evaluate through a review of scientific literature how the changes of titanium implants can interfere with the process of adhesion and proliferation of both cells and bacteria. Some studies show that the surface treatment influences the early stages of osseointegration however there is an increase in the number of osteoblasts but a change in the pattern of cell adhesion. And concerning to the biological area, chemical characteristics influence the topographic features for both cells and bacterian the most

Porphyromonas gingivalis decreases osteoblast proliferation through IL-6-RANKL/OPG and MMP-9/TIMPs pathways.

Background: Porphyromonas gingivalis, an important periodontal pathogen, is closely associated with inflammatory alveolar bone resorption. This bacterium exerts its pathogenic effect indirectly through multiple virulence factors, such as lipopolysaccharides, fimbriae, and proteases. Another possible pathogenic path may be through a direct interaction with the host's soft and hard tissues (e.g., alveolar bone), which could lead to periodontitis. Aims and Objectives: The aim of the present study was to investigate the direct effect of live and heat-inactivated P gingivalis on bone resorption, using an in vitro osteoblast culture model. Results: Optical microscopy and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide MTT assay revealed that live P gingivalis induced osteoblast detachment and reduced their proliferation. This effect was specific to live bacteria and was dependent on their concentration. Live P gingivalis increased IL-6 mRNA expression and protein production and downregulated RANKL and OPG mRNA expression. The effect of live P gingivalis on bone resorption was strengthened by an increase in MMP-9 expression and its activity. This increase was accompanied by an increase in TIMP-1 and TIMP-2 mRNA expression and protein production by osteoblasts infected with live P gingivalis. Conclusion: Overall, the results suggest that direct contact of P gingivalis with osteoblasts induces bone resorption through an inflammatory pathway that involves IL-6, RANKL/OPG, and MMP-9/TIMPs.

Surface morphology of immunocompetent cells isolated from spleen of Bufo himalayanus (Günther).

Immunocompetent cells were isolated from spleen of B. himalayanus and studied surface morphology of the three different cell types--(i) plastic adherent; (ii) nylon wool adherent; and (iii) nylon wool non-adherent cells. As revealed by scanning electron microscopy, they resembled the macrophages, B and T cells, respectively. Presence of such cell types indicated that Bufo himalayanus possessed a well-organized immune system. Further work is needed to characterize the functional efficacy of these immunocompetent cells found in B. himalayanus.

Contribution of CD4+ T cells to the early mechanisms of ischemia- reperfusion injury in a mouse model of acute renal failure

Renal ischemia-reperfusion (IR) injury is the major cause of acute renal failure in native and transplanted kidneys. Mononuclear leukocytes have been reported in renal tissue as part of the innate and adaptive responses triggered by IR. We investigated the participation of CD4+ T lymphocytes in the pathogenesis of renal IR injury. Male mice (C57BL/6, 8 to 12 weeks old) were submitted to 45 min of ischemia by renal pedicle clamping followed by reperfusion. We evaluated the role of CD4+ T cells using a monoclonal depleting antibody against CD4 (GK1.5, 50 æ, ip), and class II-major histocompatibility complex molecule knockout mice. Both CD4-depleted groups showed a marked improvement in renal function compared to the ischemic group, despite the fact that GK1.5 mAb treatment promoted a profound CD4 depletion (to less than 5 percent compared to normal controls) only within the first 24 h after IR. CD4-depleted groups presented a significant improvement in 5-day survival (84 vs 80 vs 39 percent; antibody treated, knockout mice and non-depleted groups, respectively) and also a significant reduction in the tubular necrosis area with an early tubular regeneration pattern. The peak of CD4-positive cell infiltration occurred on day 2, coinciding with the high expression of ßC mRNA and increased urea levels. CD4 depletion did not alter the CD11b infiltrate or the IFN-g and granzyme-B mRNA expression in renal tissue. These data indicate that a CD4+ subset of T lymphocytes may be implicated as key mediators of very early inflammatory responses after renal IR injury and that targeting CD4+ T lymphocytes may yield novel therapies.

Avaliação do efeito da esplenectomia e auto-implante esplênico sobre algumas funções de monócitos em crianças com esquistossomose mansônica / Evaluation of the effect of splenectomy with autologous spleen tissue implantation in some monocyte functions in children with hepatosplenic schistosomiasis mansoni

Investigamos em portadores de esquistossomose hepatoesplênica após esplenectomia com ou sem auto-implante esplênico: índice de aderência, produção de superóxido (SP) e de TNF-alfa em monócitos, tratados ou não com tuftsina. Avaliamos três grupos: voluntários sadios CG (grupo controle) (n=12); esplenectomizados com auto-implante AG (n=18) e esplenectomizados sem auto-implante WAG (n=9). índice de aderência e TNF-alfa não diferiram entre os grupos. SP foi semelhante em CG e AG na 1ª hora após estimulação celular. SP foi maior em todos intervalos de tempo nos grupos CG e AG, comparados ao WAG. O tratamento com tuftsina recuperou o padrão de normalidade de SP em AG, com aumento da 1ª para a 2ª hora nos níveis do CG. O tratamento com tuftsina não alterou SP em WAG, permanecendo reduzida em todos intervalos. O auto-implante esplênico parece recuperar e manter os parâmetros imunológicos avaliados, que têm participação importante na resposta do hospedeiro às infecções.

Neuro-immunomodulation by dorsolateral hippocampus--role of macrophages,T and B cells.

In dorsolateral hippocampal lesioned, Sham and control animals, the total number of splenocytes was determined and macrophages, B cells and T cells were isolated and their percentage distribution in total splenocytes were determined. The leukocyte migration inhibition was studied in these groups using different fractions of splenocytes namely whole splenocytes, macrophage removed fraction, and nylon wool eluted T cell population. The same groups were also studied after an antigenic challenge. The results indicate alterations in the macrophages, adherent cell population as well as T cell population in lesioned and Sham animals and also in their immunized groups. These altered cell sub-populations may be responsible for the altered migration.

Obtention of rabies antigen through BHK21 cells adhered to microcarriers

Foram produzidos quatro lotes de antigeno rabico a partir de suspensoes de virus resultantes de celulas BHK21 infectadas, aderidas a microcarregadores do tipo Cytodex 1 e cultivadas em biorreator. Em paralelo foi utilizada a metodologia de producao de virus rabico com celulas BHK21 em monocamadas, contidas em garrafas de 350cm2. Os resultados encontrados demonstraram que os titulos infectantes foram de 10 elevado a 6.69 DL50/mL para as suspensoes virais obtidas em garrafas e 10 elevado a 7.28 DL50/mL para as do biorreator. Os volumes das suspensoes virais colhidas foram, em media de 11.900 mL por lote do biorreator e 800 mL por garrafa. Com o antigeno produzido no biorreator foram imunizados 10 cavalos. As medias dos titulos de anticorpos anti-rabicos encontrados nos soros destes animais foram de 240 e 212 UI/mL, respectivamente apos a base e o primeiro reforco. Atraves da infeccao de celulas BHK21 aderidas, a microcarregadores e cultivadas em biorreator, pode-se obter antigeno rabico em larga escala e com titulos infectantes satisfatorios

Inmunorreacción de los anticuerpos monoclonales A3, E1 y P3 en tejido normal / Immunoreaction of the monoclonal antibodies A3, E1 and P3 in normal tissue

Conocer el reconocimiento tisular en órganos normales de estos anticuerpos monoclonales (AcMs) dirigidos contra moléculas de gangliósidos es importante como parte de su evaluación para uso diagnóstico. Las muestras fueron procesadas frescas y posteriormente fijadas en paraformaldehído. Los 3 sobrenadantes de cultivo se trabajaron puros y en todos los experimentos se utilizaron controles negativos y positivos. Los 3 AcMs reaccionaron con células del epitelio intestinal y el tejido conectivo de la submucosa. Los antígenos A3 y E1 se localizaron también en el epitelio traqueobronquial. El AcM E1 reaccionó con los epitelios renal y prostático que el A3 lo hizo en la epidermis y los ganglios autónomos mientéricos. La inmunotinción de las secreciones renales e intestinales con estos AcMs junto a las características del marcaje tisular pudieron sugerir la naturaleza de estos antígenos

Alteraciones de la fagocitosis en el asma bronquial / Alterations of phagocytosis in bronchial asthma

La fagocitosis es una función primordial en los padecimientos broncopulmonares. Es importante su valoración en asma bronquial porque se han encontrado alteraciones tanto congénitas como adquiridas en esta enfermedad, lo que hace importante su estudio. Utilizamos leucocitos polimorfonucleares para estudiar los cuatro pasos de la fagocitosis: adherencia inmunitaria, receptores celulares, endocitosis y digestión en 52 pacientes con asma bronquial extrínseca sin tratamiento previo que alteraran la fagocitosis. Conclusión: No encontramos diferencias significativas en los pacientes asmáticos en relación con individuos normales

Slow cluster formation of purified human or rhesus T cells requires protein kinasse C and LFA-1

Ab: Homotropic T cell adhesion, as generally studied, consists of a rapid, transient binding process that is measured over a 15-120 min. period. Here we report a slow type of adhesion process occurring with human or rhesus T cells, purified from peripheral blood, that manifests itself by the formation of rounded, multi-layer clusters which may contain hundreds of cells. The maximal number and size of the clusters peak 1-2 days after the addition of phorbol ester, an absolute requirement. The number of clusters formed is proportional to phorbol ester concentration up to 1.25 ng/mL. Phorbol esters such as phorbol myristate acetate (PMA), phorbol dibutyrate (PDB), and 7-octylindolactam (OIL) induced optimal cluster formation at 1-13 ng/mL, levels slightly higher than that required to induce mitogenesis of purified T cells. Phorbol itself and the alpha-form of the ester were inactive. Both cluster formation and mitogenesis (stimulated by Con A or anti-CD3) are completely inhibited by staurosporin at 12.5 ng/mL. Even at 2.5 ng/mL, 74 percent of cluster formation was inhibited, which strongly implies a crucial role for protein kinase C. In the presence of accessory cells, T cell clusters were suppressed. Monoclonal Ab such as anti-CD3, mouse anti-CD3 followed by anti-mouse IgG, anti-CD4, anti-CD4A, anti-CD2, anti-CD8, and anti-CD45 did not induce cluster formation. None were inhibitory or stimulatory in the presence of PMA, except for anti-CD3 which enhanced cluster formation by 26 percent. However, anti-LFA-1 beta-chain (mouse monoclonal) completely blocked cluster formation over the range studied (63-1000 ng/mL) for both human and rhesus cells; rat anti-LFA-1 only blocked human cell adhesion. Anti LFA-1 only partially inhibited T cell mitogenesis. These results show that slow cluster formation shares the LFA-1 and phorbol ester requirements of the rapid adhesion of T cells requiring LFA-1 and ICAM-1. However, cluster occurs at a very low phorbol ester concentration, appears more sensitive to staurosporin inhibition, and is not stimulated via the TCR receptor like the rapid adhesion process. We hypothesize that certain neuronal processes, induced by phorbol ester, and which also show a similar protein kinase C activation time course, may share mechanisms in common with cluster formation

Depressed specific and nonspecific immune responses in secondary Brugia pahangi infection in jirds.

The immune responsiveness to specific antigens or mitogens was examined in jirds after primary and secondary infections with Brugia pahangi. When spleen cells were obtained from secondarily infected jirds, their proliferative responses to mitogens such as Con A or LPS, or to specific antigens prepared from infective larvae or adult worms were significantly lower than those of spleen cells obtained from primarily infected jirds. The proliferative responses of the peripheral blood mononuclear cells obtained from animals undergoing primary and secondary infections also showed a similar tendency. The depressed proliferative responses of the secondary infected spleen cells to Con A or LPS was partially restored by removing adherent/phagocytic cells from the original cell populations. After deletion of the adherent cells, however, antigen-specific proliferative responses were not altered and remained at low level. These results suggest that at least two different mechanisms of depression, namely adherent cell-mediated antigen-nonspecific suppression and unresponsiveness of lymphocytes to filarial antigens, are induced in jirds in the secondary infection.

La fibronectina y la adherencia de microorganismos patógenos / Fibronectin and the adherence of pathogenic microorganisms

La fibronectina (Fn) es uno de los principales componentes de la superficie celular, las matrices extracelulares y el plasma. La constituyen un dímero con dos cadenas polipeptícas de 250 kDa. Su estructura primaria está formada con base en unidades de repetición, originando los dominios de unión a diversas moléculas. La integrina Ó ß participa como el principal receptor celular de Fn. La fibronictina participa en procesos inmunológicos de fagocitosis, inflamación y opsonización, favoreciendo la depuración de bacterias y retos celulares. Juega un papel relevante en la cicatrización durante la hemostásis. En la superficie celular puede unirse a diferentes microorganismos, favoreciendo su colonización, siendo la primera etapa en la epatogénesis de diversas enfermedades infecciosas. En Staphylococcus aureus la proteína FnBp une al fragmento de 29 kDa de amino terminal de la Fn, sitio comparativo por Streptococcus pyogenes donde la proteína Sfb parece ser el ligando de la bacteria y no el ácido lipoteicóico (ALT). La Fn favorece la adherencia de bacterias gram positivas, su ausencia en la otofaringe favorece la colonización de bacterias gram negativas. Especies bacterianas de la cavidad orofaringea provocan la proteólisis de Fn y pueden participar indirectamente en la regulación de la flora cuando afectan los niveles de Fn en las superficies celulares. Treponema pallidum se une al sitio de reconocimiento celular de la Fn mediante una proteína semejante a la integrina (B 1) Entamoeba histolytica y schistosoma provocan una degradación de la Fn para poder invadir los tejidos epiteliales. Los parásitos intracelulares como Leishmania y Trypanosoma cruzi se adhieren a la Fn, utilizándola para facilitar su entrada a las células que infectan. La Fn puede unir virus y partículas virales favoreciendo la acción depuradora en este tipo de infecciones. Su amplia distribución en el organismo y su multifunsionalidad la hacen ser una proteína determinante en los procesos homeostásicos y de gran interés como un determinante en colonización e infección