Interferon-γ and Interleukin-10 Responses during Clinical Malaria Episodes in Infants Aged 0-2 Years Prenatally Exposed to Plasmodium falciparum: Tanzanian Birth Cohort

The involvement of cytokine gene polymorphism in determining the vulnerability to Blastocystis and Helicobacter pylori co-infection in the Egyptian population

AIMS

The present study aimed to identify any potential association between IL-1β and TNF-α gene polymorphism and the risk of Blastocystis infection as well as co-infection of Blastocystis with Helicobacter pylori (H.pylori).

METHODOLOGY

A total of 314 stool samples were collected and examined microscopically for the detection of parasitic infection. DNA was extracted from all samples and utilized to identify Blastocystis molecularly. Positive samples were used for H. pylori detection by rapid tests and PCR. Moreover, we investigate polymorphism in the TNF-α gene at position -1031T/C, -308 G/A, and IL-1β at position +3954C/T using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.

RESULTS

Out of the 314 stool samples, Blastocystis was detected in 93 (29.6 %); among them, 54 (58.1 %) had a mixed infection of Blastocystis with H. pylori. The TT genotype of the IL-1β gene at position +3954 was significantly higher in Blasocystis-infected patients than in uninfected patients (17.2% vs. 6.3 %, P = 0.02), which might be considered a risk factor (OR = 3.2; CI =1.21-8.52). The TNF-α at position -1031 TT genotype was significantly higher in Blastocystis-infected patients than uninfected patients (44.1% vs. 10.8 %, P< 0.0001). The T allele (OR= 2.67; CI=1.51-4.72, P = 0.0008) might be considered a risk factor. The TNF- α at position -308 AA genotype is higher in Blasocystis infected than uninfected (17.2% vs 7.2 %, P = 0.03). TNF-α -308 AA (OR = 2.72; CI = 1.08-6.89) and A allele (OR= 1.46; CI= 0.797-2.66) might be considered risk factors. The TNF- α at position -308 G/A showed that the GG is the most frequent genotype in Blastocystis with H. pylori-positive patients with a significant association (P = 0.004), as well as the G allele (P = 0.02). The G allele (OR=1.924; CI= 1.071-3.454) might be considered a risk factor for co-infection of Blastocystis and H. pylori.

CONCLUSION

SNPs (-1031 T/C and -308 G/A) of the TNF-α and (+3954 C/T) of the IL-1β may be a useful marker in the assessment of the risk of Blastocystis infection, and TNF-α at position -308 G/A) may be a predictor for co-infection of Blastocystis with H. pylori.

Elevation of serum interleukin-1β levels as a potential indicator for malarial infection and severe malaria: a meta-analysis

BACKGROUND

Interleukin (IL)-1β is a proinflammatory cytokine that has a role in disease-related inflammation, including malaria. However, reports on the effect of IL-1β on malaria severity are inconsistent. Therefore, meta-analyses to compare differences in IL-1β levels between patients with severe malaria, patients with uncomplicated malaria and healthy controls were performed.

METHODS

The PRISMA standards were used to perform a systematic review and meta-analysis. A search of PubMed, Scopus, EMBASE and reference lists was conducted for articles providing data on IL-1β levels between patients with severe malaria, patients with uncomplicated malaria and healthy controls between January 1988 and March 2022, using a combination of search terms. The quality of all studies included in this review was determined using the Strengthening the Reporting of Observational Studies in Epidemiology statement: guidelines for reporting observational studies. The evidence was synthesized quantitatively and qualitatively. The differences in IL-1 levels across participant groups were recounted narratively for qualitative synthesis. For quantitative synthesis, the mean difference in IL-1β levels across groups of participants was calculated using a random effects meta-analysis. The publication bias was assessed using funnel plots, Egger's test and a contour-enhanced funnel plot.

RESULTS

A total of 1281 articles were discovered, and the 17 that satisfied the inclusion criteria were included for syntheses. The meta-analysis results using data from 555 cases of severe malaria and 1059 cases of uncomplicated malaria showed that severe malaria had a higher mean of IL-1β levels than uncomplicated malaria (P < 0.01, pooled mean difference: 1.92 pg/mL, 95% confidence interval: 0.60-3.25 pg/mL, I2: 90.41%, 6 studies). The meta-analysis results using data from 542 cases of uncomplicated malaria and 455 healthy controls showed no difference in mean IL-1β levels between the two groups (P = 0.07, pooled mean difference: 1.42 pg/mL, 95% confidence interval: - 0.1-2.94 pg/mL, I2: 98.93%, 6 studies).

CONCLUSION

The results from the meta-analysis revealed that IL-1β levels were higher in patients with severe malaria than in patients with uncomplicated malaria; however, IL-1β levels were similar in patients with uncomplicated malaria and healthy controls. Based on the limitations of the number of studies included in the meta-analysis and high levels of heterogeneity, further studies are needed to conclude that differences in IL-1β levels can be useful for monitoring the malaria severity.

High level of soluble human leukocyte antigen (HLA)-G at beginning of pregnancy as predictor of risk of malaria during infancy

Placental malaria has been associated with an immune tolerance phenomenon and a higher susceptibility to malaria infection during infancy. HLA-G is involved in fetal maternal immune tolerance by inhibiting maternal immunity. During infections HLA-G can be involved in immune escape of pathogens by creating a tolerogenic environment. Recent studies have shown an association between the risk of malaria and HLA-G at both genetic and protein levels. Moreover, women with placental malaria have a higher probability of giving birth to children exhibiting high sHLA-G, independently of their own level during pregnancy. Our aim was to explore the association between the level of maternal soluble HLA-G and the risk of malaria infection in their newborns. Here, 400 pregnant women and their children were actively followed-up during 24 months. The results show a significant association between the level of sHLA-G at the first antenatal visit and the time to first malaria infection during infancy adjusted to the risk of exposure to vector bites (aHR = 1.02, 95%CI [1.01–1.03], p = 0.014). The level of sHLA-G is a significant predictor of the occurrence of malaria infection during infancy consistent with the hypothesis that mother sHLA-G could be a biomarker of malaria susceptibility in children.