Macrophage heterogeneity generated by differential gene expression
Yang, Sung-Don
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/20589
Description
Title
Macrophage heterogeneity generated by differential gene expression
Author(s)
Yang, Sung-Don
Issue Date
1995
Doctoral Committee Chair(s)
Gaskins, H. Rex
Department of Study
Animal Sciences
Discipline
Animal Sciences
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Biology, Molecular
Biology, Cell
Language
eng
Abstract
Macrophages (mos) exist as functionally heterogeneous populations. Mos derived from bone marrow precursor cells using either colony-stimulating factor-1 (CSF-1) or granulocyte/macrophage colony-stimulating factor (GM-CSF) have been studied to determine the distinct functional phenotypes both constitutively and after stimulation. In the present study, mo heterogeneity was examined by a subtraction cDNA library to identify genes differentially expressed by distinct mo populations constitutively and after activation by IFN-$\gamma.$ Cultures of bone marrow-derived mos were treated with 50 U/ml IFN-$\gamma$ for 40, 70 and 140 min to induce or enhance expression of early responsive genes regulated by IFN-$\gamma,$ and these stimulated mos were pooled. Poly(A)$\sp+$ RNA was prepared from both unactivated and IFN-$\gamma$-stimulated mos, and cDNA libraries were constructed in ZAP-II. Genes commonly expressed by both untreated and activated mo populations were removed by subtraction using biotin-avidin precipitation of hybrid complexes. Further selection was performed using differential screening of cDNAs prepared from mRNA from unactivated mos, followed by colony hybridization to remove sister clones.
Of 31 clones randomly selected from the subtraction library, five clones showed intrinsic differential expression between GM-CSF- and CSF-1-derived mos, and another five clones revealed induced or enhanced expression by IFN-$\gamma$ in GM-CSF-derived mos. In CSF-1-derived mos, these ten cDNA clones were either not expressed (GM2B1 and the small RNA species of GM3E1) or constitutively expressed (GM3A2, large mRNA species of GM3E1, GM4A12, GM2A12 and GM2B8). Four clones (GM3D7, GM1A2, GM1B4 and GM1F2) even showed reduced expression following IFN-$\gamma$ stimulation in CSF-1-derived mos. These cDNAs, except GM2B1 and GM3A2, were not significantly homologous with known DNA sequences, implying that they represent novel cDNAs differentially expressed by distinct mo populations before or after treatment with IFN-$\gamma.$ These data imply that the functional heterogeneity of bone marrow-derived mos (BMDMs) may be due to differential expression of as yet unidentified genes. Additional analysis of these cDNAs and their deduced amino acid sequences are discussed on the basis of the possible implication of these cDNAs in mo heterogeneity induced by different hematopoietic stimuli.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
