Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1995-12-28
pubmed:abstractText
Members of the Janus family (JAK) of protein tyrosine kinases are critical enzymes in signaling pathways via hematopoietin receptors. We have cloned JAK3, which unlike other known family members (JAK1, JAK2, and TYK2) is preferentially expressed in hematopoietic cells but not in a variety of other cells. Functionally, JAK3 and JAK1 are coupled to the receptors for IL-2, IL-4, IL-7, IL-9, and IL-15 in T cells and NK cells. Because of the importance of IL-2, IL-4, and IL-7 in B cell physiology, we sought to determine whether JAK3 was also present in B lymphocytes and whether it was involved in signaling via cytokines that are important for B cell development and function. In this report, we demonstrate that JAK3 is expressed in normal human peripheral blood B cells at levels that are comparable to those in T cells. In addition, the levels were found to be markedly up-regulated following stimulation with staphylococcal protein A Cowan and anti-CD40 Abs. In addition, IL-4 and IL-7 induced the rapid tyrosine phosphorylation of JAK3 and JAK1, and IL-4 activated both JAK3 and JAK1 phosphotransferase activity. JAK3 protein was also detected in immature B cell lines, but not in more well differentiated cell lines. Additionally, JAK3 was detected in lysates from bone marrow lymphoblasts of patients with B cell precursor acute lymphocytic leukemia and cell lines derived from human B cell lymphomas. Together, these data suggest that the regulation of JAK3 expression and activity is likely to be important in B cell development and function.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
155
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5220-6
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Regulation of JAK3 expression and activation in human B cells and B cell malignancies.
pubmed:affiliation
Lymphocyte Cell Biology Section, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, MD 20892, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't