Kristina E. M. Persson’s research while affiliated with Lund University and other places

Hepcidin is an essential regulator of systemic iron availability mediating both iron uptake from the diet and its release from body stores. Abnormally high hepcidin levels resulting from inflammation in chronic diseases cause iron restriction with the onset of anemia. Restoring physiological levels of hepcidin could contribute to ameliorating anemia in these patients. Heparin derivatives are known to suppress hepcidin expression acting on the BMP/SMAD pathway. The novel heparin derivative sevuparin, modified to markedly reduce its anticoagulant activity, is proposed as a promising hepcidin antagonizing strategy. Sevuparin was tested for its anti‐hepcidin properties in vitro in HepG2 cells, in vivo in mice, and in healthy volunteers. Sevuparin strongly suppressed basal, BMP6‐, and IL6‐dependent hepcidin expression in HepG2 cells in a dose‐ and time‐dependent manner, modulating the essential BMP6/SMAD cascade. These effects were evident in C57BL/6J mice after intravenous injection of a single dose of sevuparin (20 mg/kg) with a 70% reduction of hepcidin mRNA. Remarkably, similar effects were observed in healthy volunteers following single subcutaneous doses at 3, 6, and 9 mg/kg with 40%–50% suppression at 3 and 6 mg/kg and 72% at 9 mg/kg. Moreover, sevuparin was able to reduce hepcidin upregulation in a mouse model of acute inflammation induced by LPS, also showing an amelioration of the inflammatory markers. Combined with its excellent safety profile, these data suggest a role for sevuparin in treating high‐hepcidin disorders.

The onset of resistance to artemisinin for malaria treatment has stimulated the quest for novel antimalarial drugs. Herein, the gold(III) coordination complexes Aubipy [Au(bipy)Cl]+ (bipy = 2,2′-bipyridine), Auphen [Au(phen)Cl]+ (phen = phenanthroline), Auterpy [Au(terpy)Cl]2+ (terpy = 2,2′;6′,2″-terpyridine), and corresponding hydrolyzed species, have been investigated as inhibitors of the Plasmodium falciparum aquaglyceroporin (PfAQP) protein by computational methods. Through an in-silico approach using an Umbrella Sampling protocol to sample how Aubipy, Auphen, and Auterpy permeate through the PfAQP, their permeability coefficients were estimated using the Inhomogeneous Solubility Diffusion (ISD) model with promising results. The efficacy of the gold complexes was then probed by an in vitro assay testing the growth inhibition in chloroquine sensitive and resistant P. falciparum strains. In accordance with the computational data, Auterpy achieved the highest efficiency with an IC50 in the nanomolar range (590 nM) on resistant strain cultures, additionally revealing a good selectivity as compared to its activity against the human aquaglyceroporin 3.

Background Malaria remains a significant public health concern, especially for the deadliest parasite, Plasmodium falciparum. During acute malaria, various cytokines, including osteopontin (OPN), regulate the immune response. OPN has been shown to be protective against malaria in mice. Nonetheless, its precise function and potential ability to control parasites during acute malaria in humans remain poorly understood. Results Blood samples were collected from Swedish adults with imported malaria, Ugandan children and adults with symptomatic malaria (including follow-up after 42 days), Ugandans with non-malarial fever and healthy individuals from both Uganda and Sweden. Parasitemia was determined by microscopy. Malaria-negative samples were verified by LAMP. OPN and interferon-γ (IFN- γ) levels were measured using ELISA. In children, OPN levels were significantly higher during acute infection compared to levels after 42 days, whereas Ugandan adults showed no difference. Swedish adults with imported malaria had elevated OPN levels compared to both Swedish controls and Ugandan adults with malaria. Parasitemia was significantly correlated with both OPN and IFN-γ levels across the entire cohort. While a significant correlation between OPN and IFN-γ was evident overall, it remained statistically significant only in Ugandan adults when analyzed by subgroups. This suggests that OPN is not just a general marker of inflammation but may be regulated differently during the development of malaria immunity. Conclusions In acute malaria, elevated OPN levels showed a stronger correlation with lack of immunity than age. These findings underscore the potential importance of OPN in malaria, particularly in non-immune individuals.

Severe babesiosis with 9.8% parasitemia was diagnosed in a patient in the Netherlands who had previously undergone splenectomy. We confirmed Babesia venatorum using PCR and sequencing. B. venatorum was also the most prevalent species in Ixodes ricinus ticks collected around the patient's home. Our findings warrant awareness for severe babesiosis in similar patients.

The spread of tick-borne disease (TBD) is escalating globally, driven by climate change and socio-economic shifts, underlining the urgency to improve surveillance, diagnostics, and control strategies. Ticks can transmit a range of pathogens increasing the risk of transmission of human and veterinary diseases such as Lyme disease, tick-borne encephalitis, theileriosis, anaplasmosis, or Crimean-Congo hemorrhagic fever. Surveillance methods play a crucial role in monitoring the spread of tick-borne pathogens (TBP). However, there are shortcomings in the current surveillance methods regarding risks related to ticks. Human-tick encounters offer a novel metric for disease risk assessment, integrating human behavior into traditional surveillance models. However, to more reliably measure tick exposure, a molecular marker is needed. The identification of antibodies against arthropod salivary proteins as biomarkers for vector exposure represents a promising avenue for enhancing existing diagnostic and surveillance metrics. Here we explore how the use of tick saliva biomarkers targeting recombinant proteins and synthetic peptides could significantly improve the assessment of TBD transmission risk and the effectiveness of vector control measures. With focused efforts on creating a biomarker against tick exposure suitable for humans and domestic animals alike, tick surveillance, diagnosis and control would be more achievable and aid in reducing the mounting threat of TBP through a One Health lens.

Background: Production of anti-phosphatidylserine (anti-PS) antibodies has been associated with malaria and can aggravate pathology. How these autoantibodies develop during early childhood in a malaria context is not known. We examined levels of anti-PS IgG and IgM antibodies in a longitudinal cohort of mother-baby pairs during birth, in the infants at 2.5, 6 months, and in mothers and their babies at 9 months postpartum. Results: There was no difference between levels of anti-PS IgG in cord blood and the mothers' peripheral blood at birth. However, anti-PS IgM levels were significantly higher in the mothers compared to the infants' cord blood, and IgM levels were steadily increasing during the first 9 months of the infants' life. In infants that had the highest anti-PS IgM levels at birth, there was a decline until 6 months with a rise at 9 months. Infants that possessed high anti-PS IgG at birth also exhibited a progressive decline in levels. When anti-PS were correlated to different fractions of B-cells, there were several correlations with P. falciparum specific atypical B cells both at birth and at 2.5 months for the infants, especially for anti-PS IgM. Anti-PS also correlated strongly to C1q-fixing antibodies at birth. Conclusion: These results show that anti-PS IgG acquired by mothers could be transferred transplacentally and that IgM antibodies targeting PS are acquired during the first year of life. These results have increased the knowledge about autoimmune responses associated with infections in early life and is critical for a comprehensive understanding of malaria vaccine functionality in endemic areas. CITATION Tijani MK, Saleh BH, Lugaajju A, Danielsson L and Persson KEM (2024) Acquisition of anti-phosphatidylserine IgM and IgG antibodies by infants and their mothers over time in Uganda.

Background Production of anti-phosphatidylserine (anti-PS) antibodies has been associated with malaria and can aggravate pathology. How these autoantibodies develop during early childhood in a malaria context is not known. We examined levels of anti-PS IgG and IgM antibodies in a longitudinal cohort of mother-baby pairs during birth, in the infants at 2.5, 6 months, and in mothers and their babies at 9 months postpartum. Results There was no difference between levels of anti-PS IgG in cord blood and the mothers’ peripheral blood at birth. However, anti-PS IgM levels were significantly higher in the mothers compared to the infants’ cord blood, and IgM levels were steadily increasing during the first 9 months of the infants’ life. In infants that had the highest anti-PS IgM levels at birth, there was a decline until 6 months with a rise at 9 months. Infants that possessed high anti-PS IgG at birth also exhibited a progressive decline in levels. When anti-PS were correlated to different fractions of B-cells, there were several correlations with P. falciparum specific atypical B cells both at birth and at 2.5 months for the infants, especially for anti-PS IgM. Anti-PS also correlated strongly to C1q-fixing antibodies at birth. Conclusion These results show that anti-PS IgG acquired by mothers could be transferred transplacentally and that IgM antibodies targeting PS are acquired during the first year of life. These results have increased the knowledge about autoimmune responses associated with infections in early life and is critical for a comprehensive understanding of malaria vaccine functionality in endemic areas.

Background: Production of anti-phosphatidylserine (anti-PS) antibodies has been associated with malaria and can aggravate pathology. How these autoantibodies develop during early childhood in a malaria context is not known. We examined levels of anti-PS IgG and IgM antibodies in a longitudinal cohort of mother-baby pairs during birth, in the infants at 2.5, 6 months, and in mothers and their babies at 9 months postpartum. Results: There was no difference between levels of anti-PS IgG in cord blood and the mothers' peripheral blood at birth. However, anti-PS IgM levels were significantly higher in the mothers compared to the infants' cord blood, and IgM levels were steadily increasing during the first 9 months of the infants' life. In infants that had the highest anti-PS IgM levels at birth, there was a decline until 6 months with a rise at 9 months. Infants that possessed high anti-PS IgG at birth also exhibited a progressive decline in levels. When anti-PS were correlated to different fractions of B-cells, there were several correlations with P. falciparum specific atypical B cells both at birth and at 2.5 months for the infants, especially for anti-PS IgM. Anti-PS also correlated strongly to C1q-fixing antibodies at birth. Conclusion: These results show that anti-PS IgG acquired by mothers could be transferred transplacentally and that IgM antibodies targeting PS are acquired during the first year of life. These results have increased the knowledge about autoimmune responses associated with infections in early life and is critical for a comprehensive understanding of malaria vaccine functionality in endemic areas. CITATION Tijani MK, Saleh BH, Lugaajju A, Danielsson L and Persson KEM (2024) Acquisition of anti-phosphatidylserine IgM and IgG antibodies by infants and their mothers over time in Uganda.