alphaB-Crystallin regulates expansion of CD11b(+)Gr-1(+) immature myeloid cells during tumor progression

• The molecular chaperone alphaB-crystallin has emerged as a target for cancer therapy due to its expression in human tumors and its role in regulating tumor angiogenesis. alphaB-crystallin also reduces neuroinflammation, but its role in other inflammatory conditions has not been investigated. Here, we examined whether alphaB-crystallin regulates inflammation associated with tumors and ischemia. We found that CD45(+) leukocyte infiltration is 3-fold increased in tumors and ischemic myocardium in alphaB-crystallin-deficient mice. Notably, alphaB-crystallin is prominently expressed in CD11b(+) Gr-1(+) immature myeloid cells (IMCs), known as regulators of angiogenesis and immune responses, while lymphocytes and mature granulocytes show low alphaB-crystallin expression. alphaB-Crystallin deficiency results in a 3-fold higher accumulation of CD11b(+) Gr-1(+) IMCs in tumors and a significant rise in CD11b(+) Gr-1(+) IMCs in spleen and bone marrow. Similarly, we noted a 2-fold increase in CD11b(+) Gr-1(+) IMCs in chronically inflamed livers in alphaB-crystallin-deficient mice. The effect of alphaB-crystallin on IMC accumulation is limited to pathological conditions, as CD11b(+) Gr-1(+) IMCs are not elevated in naive mice. Through ex vivo differentiation of CD11b(+) Gr-1(+) cells, we provide evidence that alphaB-crystallin regulates systemic expansion of IMCs through a cell-intrinsic mechanism. Our study suggests a key role of alphaB-crystallin in limiting expansion of CD11b(+) Gr-1(+) IMCs in diverse pathological conditions.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Cell- och molekylärbiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Cell and Molecular Biology (hsv//eng)

Nyckelord

Animals

Antigens

CD11b/*immunology

Base Sequence

Bone Marrow Cells/*immunology

Cell Differentiation

Crystallins/*physiology

DNA Primers

Disease Progression

Humans

Mice

Mice

Inbred C57BL

Teratocarcinoma/immunology/*pathology

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)