Mikael Karlsson Group

B cell biology team

Antibodies produced by B cells protect us from invading pathogens such as virus and bacteria but they can also induce harmful reactions and play a key role in many of the major diseases affecting humanity. For example, in autoimmune diseases they take part in the destruction of the tissue and organs affected, and in allergy they participate in the activation of the acute inflammatory response that can sometimes be fatal. The objective of our research effort is to define the mechanisms behind activation and regulation of the antibody production in disease through a B cell perspective. In recent years it has become evident that the pre-immune B cell repertoire consists of functional subtypes that differ not only in their anatomical location but also in their antibody repertoires, and thresholds for activation. We investigate how these B cell subtypes are recruited and regulated via their interactions both with antigen presenting cells and different types of T cells. In addition we investigate other effector mechanisms mediated by B cells including their ability to secret inflammatory mediators. The goal is to gain understanding how to interfere with mechanisms leading to faulty antibody production and other B cell mediated activities that add to disease development. To do this we will use a translational approach and combine observations from clinical cohorts with experimental mechanistic in vitro and in vivo investigation

The picture summarizes the focus of our research. The nature of the antigen (Ag): self vs non-self will directly or indirectly affect B cell activation, including T cell dependency. The B cell will interact with different immune cells, including APCs and various innate lymphocytes that regulate access to antigen and provide soluble factors. Also Pattern Recognition Receptors (PPRs) such as scavenger receptors will influence the outcome of B cell activation and behavior.

Current projects and directions of our research

Current Projects Information Here



Mikael Karlsson

Organizational unit: Mikael Karlsson group
E-mail: Mikael.Karlsson@ki.se

Mikael Karlsson graduated from Uppsala University 1997 and received his Ph.D. in 2000 from the same University where he studied under Prof. Birgitta Heyman. In 2005 he completed his postdoctoral research at the Rockefeller University in New York in the lab of prof. Jeffrey Ravetch. After this he joined the faculty at Dept. of Medicine at Karolinska Institutet, Stockholm receiving an Assistant prof. position appointed by the Swedish Research Council. In 2009 he became Associate professor and in 2010 he received a senior research position appointed by the Swedish Research Council. Since 2016 he is a Professor of Immunology at the department of Microbiology, Tumor and Cell biology. Dr Karlsson is an elected member of the Henry Kunkel Society of Immunology as well as a co-chair of the Swedish Society for Immunology and head of the KI inflammation and immunology network (KiiM).

Work: +46 8 524 86175
Fax: + 46 8 524 87150

MTC, Box 280,
Nobels väg 16
Karolinska Institutet
S-171 77 Stockholm,


Group Members

Laboratory manager

Emma Lindh

Organizational unit: Mikael Karlsson group
E-mail: Emma.Lindh@ki.se

Graduate Student

Vanessa Boura

Organizational unit: Mikael Karlsson group
E-mail: vanessa.boura@ki.se

The role of B cells in cancer stroma

Graduate Student

Silke Sohn

Organizational unit: Mikael Karlsson group
E-mail: silke.sohn@ki.se

Macrophage and Dendritic cells in cancer immunotherapy

NKT cell regulation of B cell activation in allergy and autoimmunity

Graduate Student

Amanda Duhlin

Phone: 08-524 860 37
Organizational unit: Mikael Karlsson group
E-mail: amanda.duhlin@ki.se

Innate B cell activation in autoimmunity and atherosclerosis.

Graduate Student

Neel Nabar

Organizational unit: Mikael Karlsson group
E-mail: neel.nabar@ki.se

affiliated to the NIH/KI PhD exchange program. Inflammasome activation and regulation of B cell responses


Manasa Garimella

Organizational unit: Mikael Karlsson group
E-mail: manasa.garimella@ki.se



Phone: 08-524 860 62
E-mail: chenfei.he@ki.se

Associated People


Pia Dosenovic, Rockefeller University, USA, laboratory of Prof. Michel Nussenzweig.


Pia Larssen (supervisor, Susanne Gabrielsson) Pia.Larseen@ki.se

Monica Centa (supervisor, Stephen Malin) monica.centa@ki.se

Melanie Pieber (supervisor, Robert Harris) melanie.pieber@ki.se

Martina Soldemo, PhD-student (supervisor Gunilla Karlsson-Hedestam) Martina.Soldemo@ki.se

Anna Zoltowska (supervisor Gunnar Nilsson) Anna.Zoltowska@ki.se

Stephanie Hiltbrunner (supervisor Susanne Gabrielsson) Stephanie.Hiltbrunner@ki.se


Erik Holmgren (Lab photographer ) Erik.Holmgren@ki.se

Malin Winerdal (Lab visual artist) Malin.Winerdal@ki.se


Anna-Maria Georgoudaki, PhD: Dissertation 2015, Karolinska Institutet. Thesis Exploring Immunotherapeutic Targets in the Tumor Microenvironment (opponent: Prof. Siamon Gordon, Oxford University, UK). Anna-Maria left the lab for a postdoc at Rockefeller University, New York, USA.

Eva Hellqvist, Postdoc: Left the lab in 2015 for a second postdoc at department of Medicine, Huddinge, Karolinska Institutet.

Mattias Forsell, Postdoc: Left the lab in 2015 for a position as Assistant Professor at Umeå University.

Kajsa Prokopec, Postdoc: Did a joint postdoc with Harvard Med. School the lab of Prof. Michael Carroll. Kajsa left the lab in 2014 to do a second postdoc at the department of Medicine, Solna, Karolinska Institutet.

Yunying Chen, Postdoc/Assistant Professor: Left the lab in 2014. Yunying studied innate B cell activation in Allergy and Autoimmunity and left to pursue a continued science career in the biotech industry.

Emilie Grasset, PhD: Dissertation 2013, Karolinska Institutet. Thesis: Regulation of B cell Responses to Modified Self (opponent: Prof. John Kearney, University of Alabama, USA). Emilie left the lab for Postdoc at Mount Sinai School of medicine, New York, USA, supported by the Swedish Research Council.

Evelina Lindmark, PhD (co-supervisor): Dissertation 2013, Karolinska Institutet. Thesis: Studies on peripheral tolerance in AIRE deficient mice (opponent Dr Eric Meffre, Yale Univ, USA). Evelina continued as postdoc at dept. of Medicine, Karolinska Institutet.

Sara Lind, PhD: Dissertation 2010, Karolinska Institutet. Thesis: Innate Mechanisms Regulating B cell Activation in Inflammatory Diseases (opponent: Prof. Ann Marshak-Rothstein, Boston, USA). Sara left the lab for postoc at MBB, Karolinska Institutet.

Fredrik Wermeling, PhD: Dissertation 2010, Karolinska Institutet. Thesis: Innate Mechanisms regulating peripheral B cell tolerance (opponent: Prof. Keith Elkon, Washington, USA). Fredrik received a  Wenner Gren fellow  postdoc fellowship and left the lab for posdoc at the Rockefeller University, New York.

Emma Lindh, PhD: (co-supervisor) Dissertation 2009, Karolinska Institutet. Thesis: The autoimmune regulator; studies of immunological tolerance in mouse and man (opponent: Prof. Susanna Cardell, Gothenburg, Sweden). Emma left the lab for employment by the ITH biotech company as senior scientist.

Nina Mattsson, MSc: Left the lab in 2005 to work as a clinical research associate (CRA) for monitoring clinical trials.



University of Toronto, Toronto, Canada: Prof. Tak Mak

Rockefeller University, New York, USA: Prof. Jeffrey Ravetch

NIH, Bethesda, USA: Prof. Susan Pierce

Harvard Medical School, Boston, USA: Prof. Michael Carroll and Prof. Michael Brenner

University of Toronto, Toronto, Canada: Assoc. Prof. Tracy McGaha

University of St Antonio, Texas, USA: Assoc. Prof. Elisabet Leadbetter

University of Erlangen-Nurnberg, Germany: Prof. Falk Nimmerjahn and Prof. Diana Dudziak

Gothenburg University, Sweden: Dr Åsa Tivesten

Karolinska Institutet, Sweden:  Prof. Göran Hansson, Dr Elisabet Svenungson, Prof. Gunilla Karlsson Hedestam, Prof. Robert Harris, Prof. Vivianne Malmström; Associate Professors, Lisa Westerberg, Susanne Gabrielsson, Benedict Chambers, Charlotte Rolny, Rikard Sandberg, Stephen Malin and Jonas Fuxe.

Uppsala University, Sweden: Dr Johan Botling

Umeå University, Sweden: Dr Malin Sund




All Mikael Karlsson Publications in PubMed

Exosomal cancer immunotherapy is independent of MHC molecules on exosomes.
Hiltbrunner S, Larssen P, Eldh M, Martinez-Bravo M, Wagner A, Karlsson M, et al
Oncotarget 2016 Jun;7(25):38707-38717

Selective Memory to Apoptotic Cell-Derived Self-Antigens with Implications for Systemic Lupus Erythematosus Development.
Duhlin A, Chen Y, Wermeling F, Sedimbi S, Lindh E, Shinde R, et al
J. Immunol. 2016 Oct;197(7):2618-26

Cutting Edge: Marginal Zone Macrophages Regulate Antigen Transport by B Cells to the Follicle in the Spleen via CD21.
Prokopec K, Georgoudaki A, Sohn S, Wermeling F, Grönlund H, Lindh E, et al
J. Immunol. 2016 Sep;197(6):2063-8

BAFF-secreting neutrophils drive plasma cell responses during emergency granulopoiesis.
Parsa R, Lund H, Georgoudaki A, Zhang X, Ortlieb Guerreiro-Cacais A, Grommisch D, et al
J. Exp. Med. 2016 Jul;213(8):1537-53

Deletion of Wiskott-Aldrich syndrome protein triggers Rac2 activity and increased cross-presentation by dendritic cells.
Baptista M, Keszei M, Oliveira M, Sunahara K, Andersson J, Dahlberg C, et al
Nat Commun 2016 Jul;7():12175

Reprogramming Tumor-Associated Macrophages by Antibody Targeting Inhibits Cancer Progression and Metastasis.
Georgoudaki A, Prokopec K, Boura V, Hellqvist E, Sohn S, Östling J, et al
Cell Rep 2016 May;15(9):2000-11

Sensitivity of dendritic cells to NK-mediated lysis depends on the inflammatory environment and is modulated by CD54/CD226-driven interactions.
Smith L, Olszewski M, Georgoudaki A, Wagner A, Hägglöf T, Karlsson M, et al
J. Leukoc. Biol. 2016 Oct;100(4):781-789

Apoptotic cell responses in the splenic marginal zone: a paradigm for immunologic reactions to apoptotic antigens with implications for autoimmunity.
McGaha T, Karlsson M
Immunol. Rev. 2016 Jan;269(1):26-43

Cognate interaction with iNKT cells expands IL-10-producing B regulatory cells.
Vomhof-DeKrey E, Yates J, Hägglöf T, Lanthier P, Amiel E, Veerapen N, et al
Proc. Natl. Acad. Sci. U.S.A. 2015 Oct;112(40):12474-9

Deletion of WASp and N-WASp in B cells cripples the germinal center response and results in production of IgM autoantibodies.
Dahlberg C, Torres M, Petersen S, Baptista M, Keszei M, Volpi S, et al
J. Autoimmun. 2015 Aug;62():81-92

Sterile inflammation in the spleen during atherosclerosis provides oxidation-specific epitopes that induce a protective B-cell response. Grasseta E, Duhlina A, Agardhb H, Ovchinnikovab O, Hägglöfa T, Forsella M, Paulsson-Berne, Hansson G, Ketelhuth D, Karlsson M. PNAS March 12 2015 doi: 10.1073/pnas.1421227112

IL-18 in inflammatory and autoimmune disease.
Sedimbi S, Hägglöf T, Karlsson M
Cell. Mol. Life Sci. 2013 Dec;70(24):4795-808

Synergistic induction of adaptive antitumor immunity by codelivery of antigen with α-galactosylceramide on exosomes.
Gehrmann U, Hiltbrunner S, Georgoudaki A, Karlsson M, Näslund T, Gabrielsson S
Cancer Res. 2013 Jul;73(13):3865-76

Independent expansion of epitope-specific plasma cell responses upon HIV-1 envelope glycoprotein immunization.
Forsell M, Soldemo M, Dosenovic P, Wyatt R, Karlsson M, Karlsson Hedestam G
J. Immunol. 2013 Jul;191(1):44-51

AIRE expressing marginal zone dendritic cells balances adaptive immunity and T-follicular helper cell recruitment.
Lindmark E, Chen Y, Georgoudaki A, Dudziak D, Lindh E, Adams W, et al
J. Autoimmun. 2013 May;42():62-70

BLyS-mediated modulation of naive B cell subsets impacts HIV Env-induced antibody responses.
Dosenovic P, Soldemo M, Scholz J, O'Dell S, Grasset E, Pelletier N, et al
J. Immunol. 2012 Jun;188(12):6018-26

Tolerance to apoptotic cells is regulated by indoleamine 2,3-dioxygenase.
Ravishankar B, Liu H, Shinde R, Chandler P, Baban B, Tanaka M, et al
Proc. Natl. Acad. Sci. U.S.A. 2012 Mar;109(10):3909-14

The inflammatory cytokine IL-18 induces self-reactive innate antibody responses regulated by natural killer T cells.
Enoksson S, Grasset E, Hägglöf T, Mattsson N, Kaiser Y, Gabrielsson S, et al
Proc. Natl. Acad. Sci. U.S.A. 2011 Dec;108(51):E1399-407

Marginal zone macrophages suppress innate and adaptive immunity to apoptotic cells in the spleen.
McGaha T, Chen Y, Ravishankar B, van Rooijen N, Karlsson M
Blood 2011 May;117(20):5403-12

Invariant NKT cells limit activation of autoreactive CD1d-positive B cells.
Wermeling F, Lind S, Jordö E, Cardell S, Karlsson M
J. Exp. Med. 2010 May;207(5):943-52

A regulatory role for macrophage class A scavenger receptors in TLR4-mediated LPS responses.
Chen Y, Wermeling F, Sundqvist J, Jonsson A, Tryggvason K, Pikkarainen T, et al
Eur. J. Immunol. 2010 May;40(5):1451-60

IL-18 skews the invariant NKT-cell population via autoreactive activation in atopic eczema.
Lind S, Kuylenstierna C, Moll M, D Jordö E, Winqvist O, Lundeberg L, et al
Eur. J. Immunol. 2009 Aug;39(8):2293-301

AIRE regulates T-cell-independent B-cell responses through BAFF.
Lindh E, Lind S, Lindmark E, Hässler S, Perheentupa J, Peltonen L, et al
Proc. Natl. Acad. Sci. U.S.A. 2008 Nov;105(47):18466-71

Class A scavenger receptors regulate tolerance against apoptotic cells, and autoantibodies against these receptors are predictive of systemic lupus.
Wermeling F, Chen Y, Pikkarainen T, Scheynius A, Winqvist O, Izui S, et al
J. Exp. Med. 2007 Oct;204(10):2259-65