Go to main content

This page in Swedish

Hazem Khalaf

Title: Senior Lecturer School/office: School of Medical Sciences

Email: hazem.khalaf@oru.se

Phone: +46 19 301093

Room: X3121

Research subject

Biology

Research environments

About Hazem Khalaf

Hazem Khalaf is a Senior Lecturer in Cellular Microbiology at the Department of Medical Sciences. He defended his PhD-thesis in 2010 at the Department of Science and Technology. The thesis describes inflammation and intracellular signaling events in response to infection and/or environmental pollutants, including pharmaceuticals and endocrine disrupting compounds. Hazem Khalaf was appointed as Associate Professor (Docent) in Biomedicine in 2016.

Development of innovative strategies to combat bacterial and viral infections are urgent. The increase in antimicrobial resistance has been dramatic, leading to limitations in treatment options. Antimicrobial peptides have become attractive candidates for therapeutic applications in traditional medicine against infections. The research focuses on understanding host-pathogen interaction, intracellular signaling processes and subsequent release of inflammatory mediators, and how these processes can be counteracted by antimicrobial peptides. Our research has resulted in new innovations for the treatment of bacterial and viral infections and identification of possible diagnostic markers.

Hazem Khalaf is teaching and have course responsibilities in the subjects of Cell Biology and Microbiology at the basic and advanced levels in Medicine and Biomedicine.

Active projects

Research teams

Publications

Articles in journals | Chapters in books | Doctoral theses, comprehensive summaries | Manuscripts |

Articles in journals

Wiman, E. , Zattarin, E. , Aili, D. , Bengtsson, T. , Selegård, R. & Khalaf, H. (2023). Development of novel broad-spectrum antimicrobial lipopeptides derived from plantaricin NC8 β. Scientific Reports, 13 (1).
Eskilson, O. , Zattarin, E. , Berglund, L. , Oksman, K. , Hanna, K. , Rakar, J. , Sivlér, P. , Skog, M. & et al. (2023). Nanocellulose composite wound dressings for real-time pH wound monitoring. Materials today. Bio, 19.
Omer, A. A. M. , Hinkula, J. , Tran, P. T. H. , Melik, W. , Zattarin, E. , Aili, D. , Selegård, R. , Bengtsson, T. & et al. (2022). Plantaricin NC8 αβ rapidly and efficiently inhibits flaviviruses and SARS-CoV-2 by disrupting their envelopes. PLOS ONE, 17 (11).
Squinca, P. , Berglund, L. , Hanna, K. , Rakar, J. , Junker, J. , Khalaf, H. , Farinas, C. S. & Oksman, K. (2021). Multifunctional Ginger Nanofiber Hydrogels with Tunable Absorption: The Potential for Advanced Wound Dressing Applications. Biomacromolecules, 22 (8), 3202-3215.
Musa, A. , Wiman, E. , Selegård, R. , Aili, D. , Bengtsson, T. & Khalaf, H. (2021). Plantaricin NC8 αβ prevents Staphylococcus aureus-mediated cytotoxicity and inflammatory responses of human keratinocytes. Scientific Reports, 11 (1).
Davies, J. R. , Kad, T. , Neilands, J. , Kinnby, B. , Prgomet, Z. , Bengtsson, T. , Khalaf, H. & Svensäter, G. (2021). Polymicrobial synergy stimulates Porphyromonas gingivalis survival and gingipain expression in a multi-species subgingival community. BMC Oral Health, 21 (1).
Bengtsson, T. , Selegård, R. , Musa, A. , Hultenby, K. , Utterström, J. , Sivlér, P. , Skog, M. , Nayeri, F. & et al. (2020). Author Correction: Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics. Scientific Reports, 10 (1).
Bengtsson, T. , Selegård, R. , Musa, A. , Hultenby, K. , Utterström, J. , Sivlér, P. , Skog, M. , Nayeri, F. & et al. (2020). Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics. Scientific Reports, 10 (1).
Eskilson, O. , Lindström, S. B. , Sepulveda, B. , Shahjamali, M. M. , Güell-Grau, P. , Sivlér, P. , Skog, M. , Aronsson, C. & et al. (2020). Self-Assembly of Mechanoplasmonic Bacterial Cellulose-Metal Nanoparticle Composites. Advanced Functional Materials, 30 (40).
Selegård, R. , Musa, A. , Nyström, P. , Aili, D. , Bengtsson, T. & Khalaf, H. (2019). Plantaricins markedly enhance the effects of traditional antibiotics against Staphylococcus epidermidis. Future microbiology, 14 (3), 195-206.
Fürsatz, M. , Skog, M. , Sivlér, P. , Palm, E. , Aronsson, C. , Skallberg, A. , Greczynski, G. , Khalaf, H. & et al. (2018). Functionalization of bacterial cellulose wound dressings with the antimicrobial peptide ε-poly-L-Lysine. Biomedical Materials, 13.
Jayaprakash, K. , Demirel, I. , Khalaf, H. & Bengtsson, T. (2018). Porphyromonas gingivalis-induced inflammatory responses in THP1 cells are altered by native and modified low-density lipoproteins in a strain-dependent manner. Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), 126 (8), 667-677.
Bengtsson, T. , Lönn, J. , Khalaf, H. & Palm, E. (2018). The lantibiotic gallidermin acts bactericidal against Staphylococcus epidermidis and Staphylococcus aureus and antagonizes the bacteria-induced proinflammatory responses in dermal fibroblasts. MicrobiologyOpen, 7 (6).
Bengtsson, T. , Zhang, B. , Selegård, R. , Wiman, E. , Aili, D. & Khalaf, H. (2017). Dual action of bacteriocin PLNC8 alpha beta through inhibition of Porphyromonas gingivalis infection and promotion of cell proliferation. Pathogens and Disease, 75 (5).
Jayaprakash, K. , Demirel, I. , Gunaltay, S. , Khalaf, H. & Bengtsson, T. (2017). PKC, ERK/p38 MAP kinases and NF-B targeted signalling play a role in the expression and release of IL-1β and CXCL8 in Porphyromonas gingivalis-infected THP1 cells. Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), 125 (7), 623-633.
Palm, E. , Demirel, I. , Bengtsson, T. & Khalaf, H. (2017). The role of toll-like and protease-activated receptors and associated intracellular signaling in Porphyromonas gingivalis-infected gingival fibroblasts. Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), 125 (2), 157-169.
Khalaf, H. , Nakka, S. S. , Sandén, C. , Svärd, A. , Hultenby, K. , Scherbak, N. , Aili, D. & Bengtsson, T. (2016). Antibacterial effects of Lactobacillus and bacteriocin PLNC8 αβ on the periodontal pathogen Porphyromonas gingivalis. BMC Microbiology, 16 (1).
Wickham, A. , Vagin, M. , Khalaf, H. , Bertazzo, S. , Hodder, P. , Dånmark, S. , Bengtsson, T. , Altimiras, J. & et al. (2016). Electroactive biomimetic collagen-silver nanowire composite scaffolds. Nanoscale, 8 (29), 14146-14155.
Zhang, B. , Sirsjö, A. , Khalaf, H. & Bengtsson, T. (2016). Transcriptional profiling of human smooth muscle cells infected with gingipain and fimbriae mutants of Porphyromonas gingivalis. Scientific Reports, 6.
Zhang, B. , Khalaf, H. , Sirsjö, A. & Bengtsson, T. (2015). Gingipains from the Periodontal Pathogen Porphyromonas gingivalis Play a Significant Role in Regulation of Angiopoietin 1 and Angiopoietin 2 in Human Aortic Smooth Muscle Cells. Infection and Immunity, 83 (11), 4256-4265.
Bengtsson, T. , Khalaf, A. & Khalaf, H. (2015). Secreted gingipains from Porphyromonas gingivalis colonies exert potent immunomodulatory effects on human gingival fibroblasts. Microbiological Research, 178, 18-26.
Palm, E. , Khalaf, H. & Bengtsson, T. (2015). Suppression of inflammatory responses of human gingival fibroblasts by gingipains from Porphyromonas gingivalis. Molecular Oral Microbiology, 30 (1), 74-85.
Jayaprakash, K. , Demirel, I. , Khalaf, H. & Bengtsson, T. (2015). The role of phagocytosis, oxidative burst and neutrophil extracellular traps in the interaction between neutrophils and the periodontal pathogen Porphyromonas gingivalis. Molecular Oral Microbiology, 30 (5), 361-375.
Klarström-Engström, K. , Khalaf, H. , Kälvegren, H. & Bengtsson, T. (2015). The role of Porphyromonas gingivalis gingipains in platelet activation and innate immune modulation. Molecular Oral Microbiology, 30 (1), 62-73.
Palm, E. , Demirel, I. , Bengtsson, T. & Khalaf, H. (2015). The role of toll-like and protease-activated receptors in the expression of cytokines by gingival fibroblasts stimulated with the periodontal pathogen Porphyromonas gingivalis. Cytokine, 76 (2), 424-432.
Elmarghani, A. , Pradhan, A. , Seyoum, A. , Khalaf, H. , Ros, T. , Forsberg, L. , Nermark, T. , Osterman, L. & et al. (2014). Contribution of pharmaceuticals, fecal bacteria and endotoxin to the inflammatory responses to inland waters. Science of the Total Environment, 488-489, 228-235.
Khalaf, H. , Lönn, J. & Bengtsson, T. (2014). Cytokines and chemokines are differentially expressed in patients with periodontitis: Possible role for TGF-beta 1 as a marker for disease progression. Cytokine, 67 (1), 29-35.
Jayaprakash, K. , Khalaf, H. & Bengtsson, T. (2014). Gingipains from Porphyromonas gingivalis play a significant role in induction and regulation of CXCL8 in THP-1 cells. BMC Microbiology, 14.
Kling, P. , Modig, C. , Mujahed, H. , Khalaf, H. , von Hofsten, J. & Olsson, P. (2013). Differential regulation of the rainbow trout (Oncorhynchus mykiss) MT-A gene by nuclear factor interleukin-6 and activator protein-1. BMC Molecular Biology, 14 (1), 28.
Palm, E. , Khalaf, H. & Bengtsson, T. (2013). Porphyromonas gingivalis downregulates the immune response of fibroblasts. BMC Microbiology, 13, 155.
Khalaf, H. , Demirel, I. & Bengtsson, T. (2013). Suppression of inflammatory gene expression in T cells by Porphyromonas gingivalis is mediated by targeting MAPK signaling. Cellular & Molecular Immunology, 10 (5), 413-422.
Zhang, B. , Elmabsout, A. A. , Khalaf, H. , Basic, V. T. , Jayaprakash, K. , Kruse, R. , Bengtsson, T. & Sirsjö, A. (2013). The periodontal pathogen Porphyromonas gingivalis changes the gene expression in vascular smooth muscle cells involving the TGFbeta/Notch signalling pathway and increased cell proliferation. BMC Genomics, 14, 770.
Khalaf, H. , Jass, J. & Olsson, P. (2013). The role of calcium, NF-κB and NFAT in the regulation of CXCL8 and IL-6 expression in Jurkat T-cells. International Journal of Biochemistry and Molecular Biology, 4 (3), 150-156.
Pradhan, A. , Khalaf, H. , Ochsner, S. A. , Sreenivasan, R. , Koskinen, J. , Karlsson, M. , Karlsson, J. , McKenna, N. J. & et al. (2012). Activation of NF-kappa B Protein Prevents the Transition from Juvenile Ovary to Testis and Promotes Ovarian Development in Zebrafish. Journal of Biological Chemistry, 287 (45), 37926-37938.
Khalaf, H. & Bengtsson, T. (2012). Altered T-cell responses by the periodontal pathogen Porphyromonas gingivalis. PLOS ONE, 7 (9).
Karlsson, M. , Scherbak, N. , Khalaf, H. , Olsson, P. & Jass, J. (2012). Substances released from probiotic Lactobacillus rhamnosus GR-1 potentiate NF-κB activity in Escherichia coli-stimulated urinary bladder cells. FEMS Immunology and Medical Microbiology, 66 (2), 147-156.
Khalaf, H. , Jass, J. & Olsson, P. (2010). Differential cytokine regulation by NF-κB and AP-1 in Jurkat T-cells. BMC Immunology, 11.
Khalaf, H. , Larsson, A. , Berg, H. , McCrindle, R. , Arsenault, G. & Olsson, P. (2009). Diastereomers of the Brominated Flame Retardant 1,2-dibromo-4-(1,2 dibromoethyl)cyclohexane Induce Androgen Receptor Activation in the HepG2 Hepatocellular Carcinoma Cell Line and the LNCaP Prostate Cancer Cell Line. Journal of Environmental Health Perspectives, 117 (12), 1853-1859.
Khalaf, H. , Salste, L. , Karlsson, P. , Ivarsson, P. , Jass, J. & Olsson, P. (2009). In vitro analysis of inflammatory responses following environmental exposure to pharmaceuticals and inland waters. Science of the Total Environment, 407 (4), 1452-1460.

Chapters in books

Khalaf, H. , Palm, E. & Bengtsson, T. (2017). Cellular Response Mechanisms in Porphyromonas gingivalis Infection. In: Pachiappan Arjunan, Periodontitis: A Useful Reference (pp. 45-68). . InTech.
Olsson, P. , Khalaf, H. & Jass, J. (2011). CXCL8 regulation and function in HIV infections and potential treatment strategies. In: Nancy Dumais, HIV and AIDS: updates on biology, immunology, epidemiology and treatment strategies (pp. 327-344). . InTech.

Doctoral theses, comprehensive summaries

Khalaf, H. (2010). Characterization and environmental influences on inflammatory and physiological responses. (Doctoral dissertation). (Comprehensive summary) Örebro: Örebro universitet.

Manuscripts

Khalaf, H. , Jass, J. & Olsson, P. Influence of growth conditions on in vitro regulation of NF-κB activity in Jurkat T-cells.
Khalaf, H. , Nakka, S. S. , Sandén, C. , Svärd, A. , Hultenby, K. , Scherbak, N. , Aili, D. & Bengtsson, T. Antibacterial effects of lactobacillus and bacteriocin NC8 αβ on the periodontal pathogen Porphyromonas gingivalis.
Musa, A. , Bengtsson, T. & Khalaf, H. Antimicrobial activity of plantaricin NC8 αβ against ESKAPE pathogens and Escherichia coli : greater specificity against gram-positive bacteria.
Nakka, S. S. , Palm, E. , Bengtsson, T. & Khalaf, H. Bacteriocin plantaricin NC8 αβ antagonizes Porphyromonas gingivalis infection and induces proliferation of gingival epithelial cells.
Nakka, S. S. , Palm, E. , Nayeri, F. , Bengtsson, T. & Khalaf, H. Effects of plantaricin NC8 αβ and antibodies on gingival epithelial cells infected by Porphyromonas gingivalis.
El Marghani, A. M. , Khalaf, H. , Jass, J. & Olsson, P. Immune cell activation by sewage treatment plant effluents and inland waters in Sweden.
Jayaprakash, K. , Demirel, I. , Gunaltay, S. , Khalaf, H. & Bengtsson, T. PKC, ERK/p38 MAP kinases and NF-κB targeted signalling plays a crucial role in expression and release of IL-1β and CXCL8 in Porphyromonas gingivalis infected monocytes.
Jayaprakash, K. , Demirel, I. , Khalaf, H. & Bengtsson, T. Porphyromonas gingivalis induced release of reactive oxygen species and interleukin-1 beta and the effects of low density lipoproteins in monocytes and whole blood.
Paramel Varghese, G. , Zhang, B. , Khalaf, H. , Ljungberg, L. U. , Sirsjö, A. , Bengtsson, T. & Fransén, K. Poryphyromonas gingivalis induces IL-1β in aortic smooth muscle cells : possible role of gingipains?.
Klarström-Engström, K. , Bengtsson, T. & Khalaf, H. The platelet response to various strains of Porphyromonas gingivalis.
Palm, E. , Demirel, I. , Bengtsson, T. & Khalaf, H. The role of toll-like and protease-activated receptors and associated intracellular signalling in Porphyromonas gingivalis-infected gingival fibroblasts.
Palm, E. , Demirel, I. , Bengtsson, T. & Khalaf, H. The role of toll-like and protease-activated receptors in the expression of cytokines by gingival fibroblasts stimulated with the periodontal pathogen Porphyromonas gingivalis.
Zhang, B. , Sirsjö, A. , Khalaf, H. & Bengtsson, T. Transcriptional profiling of human smooth muscle cells infected with gingipain and fimbriae mutants of Porphyromonas gingivalis.
Khalaf, H. , Ochsner, S. A. , Koskinen, J. , Karlsson, M. , Karlsson, J. , Sreenivasan, R. , McKenna, N. J. , Orban, L. & et al. Zebrafish feminization in response to heat killed bacterial exposure suggests a function for anti-apoptotic genes in oocyte maintenance.