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Entamoeba histolytica produces, in axenic culture, the monocytes locomotion inhibitory factor (MLIF), a oligopeptide with selective anti-inflammatory properties. We evaluated the effect of MLIF on the expression of pro- and anti-inflammatory cytokines in CD4+ T lymphocytes from children with asthma and allergic rhinitis. Twelve children with severe asthma, 12 children with allergic rhinitis and 6 healthy controls were recruited for this study between May and December 2016. CD4+ T cells were cultured for 24 h at 37°C, 5% CO2 in the presence of MLIF, 1-phorbol 12-myristate 13-acetate (PMA), MLIF+PMA or RPMI. Interleukin-10 (IL-10), IL-4, interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) expression levels were measured in the supernatants of T-cell cultures using the enzyme-linked immunosorbent assay (ELISA). Pro- and anti-inflammatory cytokines were inhibited by MLIF (IFN-γ p=0.0036, TNF-α p

Entamoeba histolytica produces, in axenic culture, the monocytes locomotion inhibitory factor (MLIF), a oligopeptide with selective anti-inflammatory properties. We evaluated the effect of MLIF on the expression of pro- and anti-inflammatory cytokines in CD4+ T lymphocytes from children with asthma and allergic rhinitis. Twelve children with severe asthma, 12 children with allergic rhinitis and 6 healthy controls were recruited for this study between May and December 2016. CD4+ T cells were cultured for 24 h at 37°C, 5% CO2 in the presence of MLIF, 1-phorbol 12-myristate 13-acetate (PMA), MLIF+PMA or RPMI. Interleukin-10 (IL-10), IL-4, interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) expression levels were measured in the supernatants of T-cell cultures using the enzyme-linked immunosorbent assay (ELISA). Pro- and anti-inflammatory cytokines were inhibited by MLIF (IFN-γ p=0.0036, TNF-α p<0.001, IL-4 p=0.0082) in asthmatic patients, however IFN-γ was not significantly inhibited (NS) in patients with allergic rhinitis when compared to the RPMI group. In CD4+ T cells treated with PMA+MLIF, the expression levels of IFN-γ, TNF-α and IL-4 were strongly inhibited (p<0.001, p<0.001 and p<0.0094), compared to PMA treatment alone, for both, rhinitis and asthma. IL-10 expression was not affected by MLIF in neither of the two diseases. We conclude that MLIF alters the pro/anti-inflammatory balance and induces inhibition of IL-4, IFN-γ and TNF-α, but does not affect IL-10.

The introduction of type b Haemophilus influenzae (Hi b) conjugate vaccines for children as part of immunization schedules has led to a sharp drop in the incidence of Hi b disease. In 1999, the Haemophilus influenzae b DTwP-HB/Hi b vaccine was introduced into the primary immunization program in Mexico. There have been no studies evaluating the vaccine after the widespread immunization in our country. The immune response to Hi b vaccines in different countries varies both quantitatively and qualitatively. Replacement of Hi b strains is expected between pre- and post-vaccination eras. Documentation on these three aspects will be useful for decisions regarding the use of the vaccine. In this review, we show and discuss the potential benefits of vaccination with DTwP-HB/Hi b in Mexico in terms of our collected data obtained during the last 8 years on population genotype variations and on concentration and avidity of IgG antibodies. As the epidemiological follow-up data are missing, the evaluation of the results of these three types of studies, as a whole, allows clarification of the scenario of the protection after vaccination in Mexico, in absence of the drop in cases reports. These results reinforce the findings of postvaccination studies done elsewhere., (Copyright 2010 IMSS. Published by Elsevier Inc. All rights reserved.)

Haemophilus influenzae type b (Hinb) is the main etiologic agent of severe pediatric illnesses, such as meningitis, epiglottitis and pneumonia. Countries most affected by this pathogen are localized in the American, European and African continents. While this organism was originally isolated 100 years ago, the first field trial using a whole killed vaccine was performed until 1959. Since then, further controlled clinical trials have mainly been conducted in the North American and European continents. Under appropriate safety and efficacy evaluation tests performed by the Federal Drug Administration Agency (FDA), five vaccines were licensed: one single and four conjugated preparations. Worldwide and regional epidemiologic data concerning serious diseases produced by this organism have shown their outstanding impact in the public health of developed countries. Unfortunately, in developing countries similar epidemiological indexes are lacking for lethal and disabling diseases, such as meningitis. In order to decrease high morbidity and mortality rates of this meningeal disease and its neurological sequelae, immunoprophylactic preventive measures have been recommended. Furthermore, some risk factors of this infant illness can also be reduced. New strategies regarding conjugate Hib-vaccines are reviewed. Finally, promising virulence factors or self Hib-structures for the production of vaccines are suggested, such as outer membrane proteins (OMP), lipooligosaccharides, fimbriae or pili.

It was compared the activity of exudate peritoneal cells (EPC) obtained from CFW mice immunized either with Salmonella typhi Ty2 ribosomal fraction or whole-cell heat inactivated vaccine, both in comparison with EPC from sham-immunized. In the group which received ribosomal preparation, a subcutaneous dose equivalent to 100 micrograms of RNA in incomplete Freund's adjuvant (IFA) was initially used and 14 days after a booster of the same dose in IFA was given. A single dose of whole-cell heat inactivated vaccine, with 10(6) bacteria in IFA was employed subcutaneously in animals of the second group. EPC from controls and immunized mice were withdrawn at periods of 7, 11, 14, 18, 22, 25, 29 and 31 days after immunization and each sample was incubated in vitro in presence of live virulent non-opsonized S. typhi Ty2 in 1:200 cell-bacteria relation. Twenty four hours after cultivation, EPC bacterial capacity was determined after cell disruption and enumeration of survival bacteria were made through viable counts. Results have shown that EPC from mice immunized were more efficient in eliminating intracellular bacteria than those which came from sham-immunized animals. Also, it was found that EPC from mice immunized with ribosomal preparation were more efficient (maximum P = 0.005) than EPC from the mice which received killed whole bacteria.