Primary Immunodeficiency, Innate Immunity and Antimicrobial peptides – Peter Bergman Research Group/The AMP-group

The group works broadly to understand the immune system in various infectious conditions, with a focus on respiratory tract infections (pneumococcus, tuberculosis, SARS CoV-2/COVID-19). We use various model systems in human cells and zebrafish. We also study cells from patients with different immunodeficiency conditions. During the pandemic, we have worked on many projects about COVID-19 in patients with primary immunodeficiency.

Patients with primary immunodeficiency

The group works with two main lines. One line relates to patients with primary immunodeficiency, where we search for underlying mechanisms that can explain increased susceptibility to infection. We start with a thorough clinical and immunological investigation and often continue with whole genome sequencing. Sometimes we find a genetic cause for the patient's problem. With this knowledge, we can recreate the mutation in various experimental systems, e.g. cells or zebrafish, which can then be infected with the same microbe that made the patient sick. This methodology allows us to study human diseases in detail and learn more that can form the basis for new diagnostics, treatment or prevention. We have extensive and close collaboration with other research groups at KI and abroad in this field, which is important for gaining access to the newest technologies.

Increase the endogenous immune system

The second line of research is based on knowledge of natural immunity and antimicrobial peptides (AMP), which we have now studied for more than 20 years. We are developing a new concept for treating infections, so-called "Host Directed Therapy". The concept is about not only attacking the bacteria with antibiotic drugs, but also increasing the endogenous immune system. We have specifically targeted AMPs, which are small peptides that are formed in the body's mucous membranes and by immune cells. AMPs kill bacteria and viruses directly but also by activating and recruiting various immune cells to the site of an infection (chemotaxis). We have discovered that vitamin D and Phenylbutyrate (PBA), together greatly increase the production of AMPs and contribute to better killing of mycobacteria in macrophages. Our goal is to identify new and more potent substances to increase the production of AMPs and how the expression of AMPs is regulated under normal conditions but also how to boost or block these systems with various drugs.

The overaching goal is to develop "Host Directed Therapy" as a new treatment against infections by experimental studies in the laboratory but also through clinical trials on patients with infectious diseases.

Ongoing projects

These projects are ongoing in close collaboration with several other research groups at KI.

  • Genetic vulnerability in severe Covid-19 infection (the COVPID study)
  • Vaccine response in immunosuppressed patients (COVAXID trial)
  • Covid-19 in patients with primary immunodeficiency – a national registry study (PIDREG study)
  • Regulation and activation of antimicrobial peptides in tuberculosis and infections caused by atypical mycobacteria.
  • Post-translational modification of AMP as a new regulatory mechanism in inflammatory skin diseases
  • Activation of AMP as a new infection treatment, so-called "Host Directed Therapy"
  • Chronic stress and the immune system - experimental and clinical studies
  • Vitamin D and respiratory tract infections – experimental and clinical studies.
  • Vitamin D and immunity in cancer patients in palliative care.

Our research in the media

Primary Immunodeficiency and Covid-19

Peter Bergman is interviewed by Malou on TV4 about severe Covid-19 in a previously healthy person (the project is presented):

Part 1 (October 2020)

https://www.youtube.com/watch?v=giMVtSIPqy8

Peter Bergman follows up and explains with the genetic investigation found in the patient.

Part 2 (March 2021)

https://www.youtube.com/watch?v=KOUhSl_eK5o

Host Directed Therapy

Publications

Selected publications

Funding

Grants

  • Swedish Research Council
    1 January 2023 - 31 December 2025
    In palliative care, all treatment aims to relieve symptoms and to maintain as high quality of life (QoL) as possible despite an incurable cancer. Cancer related fatigue (CRF) is one of the most distressing symptoms for cancer patients that impair QoL the most. Today, there is a lack of effective and safe pharmacological treatment for CRF in palliative care. We recently conducted a large clinical study where we found that Vitamin D treatment reduced the need for opiod use in palliative cancer patients. In addition, we found that Vitamin D reduced CRF. To confirm these results, we are now planning a new clinical study that completely focuses on CRF where 200 patients will be randomized to low dose vitamin D (400 IU/day) or high dose (4000 IU/day) for 16 weeks. The mechanisms for how Vitamin D can affect CRF will be studied by measuring proinflammatory markers and levels of oxysterols in the blood, which in turn can affect brain functions and possibly CRF.We want to answer the following questions: 1) Can Vitamin D reduce CRF and what is the optimal dose and blood concentration of vitamin D? 2) Can Vitamin D reduce CRF by decreasing inflammation and affecting 27-OHcholesterol levels? 3) Are high vitamin D levels harmful to cancer patients due to elevated levels of fibroblast growth factor 23 (FGF23)?Both positive and negative results are important in this study as there is currently lack of evidence whether Vitamin D can be used against CRF in palliative cancer care.
  • Swedish Research Council
    1 December 2022 - 30 November 2025
    Patients with primary immunodeficiency have been severely affected by the COVID-19 pandemic with an increased risk of infection and severe disease. During the pandemic, we changed our planned research and focused on helping this vulnerable group of patients. We applied our concept with screening, advanced diagnostics and targeted treatment and prevention. This turned out to be very successful with direct benefit for patients but also led to scientific progress at the highest international level. We have been able to identify three completely new immunodeficiency diseases that increase the susceptibility to COVID-19: TLR7 deficiency, IRF7 deficiency and autoantibodies to interferon-alpha. We have also conducted a large clinical study where the effect of COVID-19 vaccine has been evaluated in patients with poor immune system. Now we want to continue to develop the concept of screening inpatients to find additional patients with underlying immunodeficiency, deepen the molecular diagnostics and integrate novel methods in clinical practise, target our treatment and follow up vaccine responses and mechanisms over time. The network that we have built up over the past two years will allow us to develop the clinical and translational research on immunodeficiency in the coming years. We believe the new knowledge can be quickly implemented in clinical care and lead to patient benefit and scientific progress both in the short and long term. (1452 ch)
  • Swedish Heart-Lung Foundation
    1 January 2021 - 31 December 2021

Staff and contact

Group leader

All members of the group

Alumni

Samuel Paulson

Avinash Padhi

Harpa Karadottir

Salma Al-Adwani

Catharina Missailidis

Monica Lindh

Maarten Coorens

Frank Nylén

Erica Miraglia

Min Wan

Research techniques

  • Cell culture
  • Work with biological samples from patients
  • Confocal microscopy
  • qPCR
  • Western blot analysis
  • Microbiological work with bacteria and fungi
  • HPLC
  • LC-MS/MS
  • Circular dichroism
  • ChIP assay
  • Flow cytometry
  • Model system in zebrafish

Teaching assignments

We regularly teach at the Medical Program, the Dental Program, the BMA program and several other programs at KI as well as in various postgraduate courses, mainly in microbiology, immunology and infection biology.