Serum Levels of Cytokines and IgE in Helminth-Infected Nigerian Pregnant Women and Children

Serum cytokine profile of pregnant women with malaria, intestinal helminths and HIV infections in Ibadan, Nigeria

Malaria, helminthiasis and HIV are widespread in developing countries taking a heavy toll on pregnant women. Due to similar environmental and human factors of transmission, they co-exist. The epidemiology and pathology of these diseases have been extensively studied but data on serum cytokine profile changes which is crucial in pregnancy is limited. The aim of this study was to evaluate the co-infections and their impact on peripheral blood cytokines. Blood and stool samples were collected from recruited 18-45-year-old pregnant women in different trimesters who were apparently healthy with no obvious complications in pregnancy. Pretested questionnaires were administered for personal and socio-demographic details. Malaria parasitemia in Giemsa-stained thick blood films was examined microscopically. Stool samples were screened for helminths using Kato-Katz method. Cytokine levels of TNF-α, IFN-γ, IL-1α, IL-2, IL-4, IL-6, IL-10, IL-12p70, IL-13 and IL-17 in 121 serum samples were determined using ELISA. Data were analysed using descriptive statistics and Mann-Whitney U test at α_0.05. Relative to the single infections, there were significant reductions in IFN-γ and IL-13 in second and third trimesters respectively in those with Plasmodium and helminth co-infection. IFN-γ and IL-17 were elevated while IL-1α and IL-12p70 were reduced in co-infection of helminths and HIV. Co-infection of Plasmodium and HIV in second and third trimesters showed significant elevations in IL-1α, IL-10 and IL-17 while TNF-α, IL-4 and IL-12p70 were significantly reduced. HIV in pregnancy and its co-infection with Plasmodium resulted in significant distortions in the cytokine profile. However, helminth and its co-infection with Plasmodium or HIV produced less changes in the cytokine profile.

Circulating IL-6, IL-10, and TNF-alpha and IL-10/IL-6 and IL-10/TNF-alpha ratio profiles of polyparasitized individuals in rural and urban areas of gabon

Malaria, blood-borne filarial worms and intestinal parasites are all endemic in Gabon. This geographical co-distribution leads to polyparasitism and, consequently, the possibility of immune-mediated interactions among different parasite species. Intestinal protozoa and helminths could modulate antimalarial immunity, for example, thereby potentially increasing or reducing susceptibility to malaria. The aim of the study was to compare the cytokine levels and cytokine ratios according to parasitic profiles of the population to determine the potential role of co-endemic parasites in the malaria susceptibility of populations. Blood and stool samples were collected during cross-sectional surveys in five provinces of Gabon. Parasitological diagnosis was performed to detect plasmodial parasites, Loa loa, Mansonella perstans, intestinal helminths (STHs) and protozoan parasites. Nested PCR was used to detect submicroscopic plasmodial infection in individuals with negative blood smears. A cytometric bead array was used to quantify interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-α in the plasma of subjects with different parasitological profiles. Median IL-6 and IL-10 levels and the median IL-10/TNF-α ratio were all significantly higher among individuals with Plasmodium (P.) falciparum infection than among other participants (p<0.0001). The median TNF-α level and IL-10/IL-6 ratio were higher in subjects with STHs (p = 0.09) and P. falciparum-intestinal protozoa co-infection (p = 0.04), respectively. IL-6 (r = -0.37; P<0.01) and IL-10 (r = -0.37; P<0.01) levels and the IL-10/TNF-α ratio (r = -0.36; P<0.01) correlated negatively with age. Among children under five years old, the IL-10/TNF-α and IL-10/IL-6 ratios were higher in those with intestinal protozoan infections than in uninfected children. The IL-10/TNF-α ratio was also higher in children aged 5–15 years and in adults harbouring blood-borne filariae than in their control counterparts, whereas the IL-10/IL-6 ratio was lower in those aged 5–15 years with filariae and intestinal parasites but higher in adults with intestinal parasitic infections. Asymptomatic malaria is associated with a strong polarization towards a regulatory immune response, presenting high circulating levels of IL-10. P. falciparum/intestinal protozoa co-infections were associated with an enhanced IL-10 response. Immunity against malaria could differ according to age and carriage of other parasites. Helminths and intestinal protozoa can play a role in the high susceptibility to malaria currently observed in some areas of Gabon, but further investigations are necessary.

The current epidemiological transition of malaria observed in Gabon included, for example, a shift in the at-risk population from children aged less than 5 years old to older children aged 5–15 years. Another consequence was the increasing number of cases of infection among adults. In view of these findings, it is important to explain this phenomenon of epidemiological modification of malaria in Gabon. Intestinal parasites and blood filariasis are endemic in Gabon. These parasites are described to alter the malaria immune response and can be implicated in the susceptibility of individuals to malaria. In Gabon, malaria presents a heterogeneous repartition. Thus, in the present study, we investigated the role of co-endemic parasitosis in the alteration of the malarial immune response by comparing Th1 (IL-6 and TNF-α) and Th2/Treg (IL-10) cytokine production between mono- and co-parasitized individuals in many localities with different epidemiological patterns of malaria. Microscopic analyses and rapid antigenic tests were performed for malaria diagnosis. The nested PCR technique was used to demonstrate the submicroscopic parasitaemia of Plasmodium sp. Then, once groups with different parasitological profiles were constituted, IL-6, IL-10 and TNF-α levels were measured in the plasma of individuals. Th2/Th1 ratios, which can indicate the level of susceptibility of individuals to malaria, were calculated. We observed that there was no interaction between Plasmodium sp. and co-endemic parasites in the present study. However, the high Th2/Th1 cytokine ratio among patients with intestinal protozoa seems to suggest that these intestinal parasites could also play a role in susceptibility to malaria as they do for helminths.

Altered Offspring Immunity in Maternal Parasitic Infections

Maternal infection during pregnancy is known to alter the development and function of offspring's immune system, leading to inappropriate immune responses to common childhood infections and immunizations. Although this is an expanding field, maternal parasitic infections remain understudied. Millions of women of reproductive age are currently at risk for parasitic infection, whereas many pregnant, chronically infected women are excluded from mass drug administration due partially to a lack of resources, as well as fear of unknown adverse fetal developmental outcomes. In areas endemic for multiple parasitic infections, such as sub-Saharan Africa, there are increased rates of morbidity and mortality for various infections during early childhood in comparison with nonendemic areas. Despite evidence supporting similar immunomodulatory effects between various parasite species, there is no clear mechanistic understanding of how maternal infection reprograms offspring immunity. This brief review will compare the effects of selected maternal parasitic infections on offspring immunity.

Pityriasis alba: Possible associations with intestinal helminths and pathogenic protozoa

BACKGROUND

The aetiology of pityriasis alba (PA) remains uncertain, and children are at risk for PA and intestinal parasites.

AIM

To determine the prevalence of intestinal parasites in PA patients and to evaluate their possible role in PA pathogenesis.

METHODS

Overall, 180 PA patients and 100 healthy individuals were enrolled. Intestinal parasites were diagnosed by triple coproscopy, and the total serum Immunoglobulin E (IgE) levels were determined by ELISA. PA patients with intestinal parasites were treated with conventional antiparasitic drugs. Patient response to antiparasitic therapy was evaluated after 6 weeks.

RESULTS

The prevalence of intestinal parasites in PA patients and controls was 60 ± 3.6% and 32 ± 4.6%, respectively (P < .0001). Regardless of the parasite species among the PA patients and control individuals, the total IgE levels were significantly higher in PA patients (P ≤ .05). The highest values of IgE were found in PA patients with Hymenolepis nana (641.7 ± 46.3 IU/mL). The total IgE level in PA patients with parasites decreased after antiparasitic therapy, but the reduction was only significant in patients with H. nana (P < .05). Complete disappearance of hypopigmented patches was observed after the elimination of H. nana, Giardia lamblia and Enterobius vermicularis in 65 ± 10.6%, 48.7 ± 8.0% and 33.3 ± 8.2% of cases, respectively. In total, a positive clinical response to antiparasitic therapy was achieved in 60 ± 4.7% of infected PA patients.

CONCLUSION

A positive clinical response to antiparasitic therapy indicates the role of intestinal parasites in PA pathogenesis. Parasitological examination is justified by the recovery of 60 ± 4.7% of infected PA patients after the elimination of intestinal parasites.

Household Air Pollution, Levels of Micronutrients and Heavy Metals in Cord and Maternal Blood, and Pregnancy Outcomes

Cooking with kerosene emits toxic pollutants that may impact pregnancy outcomes. Sixty-eight women in their first trimester of pregnancy, kerosene users (n = 42) and liquefied natural gas (LNG) users (n = 26), were followed until birth. Maternal and cord blood were collected immediately after birth. Levels of micronutrients and heavy metals were quantified. Pregnancy outcomes (gestation age (GA), birth weight (BW), and chest and head circumference) were also measured. Mean (± standard deviation (SD)) age of mothers in kerosene and LNG groups were similar (p = 0.734). Mean (±SD) BW of newborns of LNG users was significantly higher compared to newborns of kerosene users (3.43 ± 0.32 vs. 3.02 ± 0.43, p < 0.001). Mean GA (in weeks) was similar between the two groups (p = 0.532). Women in the kerosene group had significantly higher cord blood levels of zinc, lead, mercury, iodine and vitamin B6 and lower levels of folic acid compared to LNG users (p < 0.05). Newborns of kerosene users had reduced levels of zinc, lead, mercury, iodine, vitamins B6 and B12, folic acid, and homocysteine compared with LNG users (p < 0.05). Also, cooking with kerosene was significantly associated with reduced birth weight after adjusting for potential confounders (β ± standard error (SE) = −0.326 ± 0.155; p = 0.040). Smoke from kerosene stove was associated with reduced birth weight and micronutrients imbalance in mothers and newborns.

Helminthic infections in returning travelers and migrants with eosinophilia: Diagnostic value of medical history, eosinophil count and IgE

OBJECTIVES

Eosinophilia in travelers and migrants returning from the tropics is often associated with invasive helminthic infections. Total IgE is considered a useful additional diagnostic parameter; however, both parameters are also increased in various other non-helminthic diseases.

METHODS

We retrospectively evaluated travelers and migrants seen at our department between September 2007 and May 2014. Patients with an absolute eosinophil count ≥500 cells/μl were considered for further analyses.

RESULTS

Among 6618 returned travelers and migrants, 154 (2.3%) had a total eosinophil count ≥500 cells/μL. Of these, 71 patients (46%) were diagnosed with helminthic infection. In an additional 62 patients (40%) with eosinophilia a final diagnosis was found, including non-helminthic infections in 34 patients and non-infectious causes in 28 patients, while in 21 patients (14%) no diagnosis was made. Patients with helminthic infections had higher eosinophil counts than travelers and migrants with other diagnoses (median 981 vs. 710 cells/μl; p = 0.001), while total IgE levels (n = 70; 172 vs. 152 kU/l; p = 0.731) were similar in both groups.

CONCLUSION

Eosinophil count but not total IgE levels are associated with helminthic infections in returning travelers and migrants with eosinophilia. Our results do not support the use of total IgE to differentiate helminthic infections from other causes of eosinophilia in this population.

Immune Profile of Honduran Schoolchildren with Intestinal Parasites: The Skewed Response against Geohelminths

Soil-transmitted helminth infections typically induce a type-2 immune response (Th2), but no immunoepidemiological studies have been undertaken in Honduras, an endemic country where the main control strategy is children's annual deworming. We aimed to characterize the immune profile of Honduran schoolchildren harbouring these parasitoses. Demographic and epidemiological data were obtained through a survey; nutritional status was assessed through anthropometry; intestinal parasites were diagnosed by formol-ether and Kato-Katz; and blood samples were collected to determine immunological markers including Th1/Th2 cytokines, IgE, and eosinophil levels. A total of 225 children participated in the study, all of whom had received deworming during the national campaign five months prior to the study. Trichuriasis and ascariasis prevalence were 22.2% and 20.4%, respectively. Stunting was associated with both age and trichuriasis, whereas ascariasis was associated with sex and household conditions. Helminth infections were strongly associated with eosinophilia and hyper-IgE as well as with a Th2-polarized response (increased levels of IL-13, IL-10, and IL4/IFN-γ ratios and decreased levels of IFN-γ). Pathogenic protozoa infections were associated with a Th1 response characterized by elevated levels of IFN-γ and decreased IL10/IFN-γ ratios. Even at low prevalence levels, STH infections affect children's nutrition and play a polarizing role in their immune system.