Human complement factor H. Tissue specificity in the expression of three different mRNA species.
Using cDNA clones H-19 and H-46, we have shown previously that three different mRNA species (4.3 kb, 1.8 kb and 1.4 kb) for complement factor H are expressed constitutively in human liver. Here we report data suggesting that the expression of these different factor-H mRNA species is regulated by tissue-specific control mechanisms. Total RNA and poly(A)-enriched RNA from various human tissues (heart, lung, temporal cortex, kidney, spleen, bone marrow and muscle) various cell lines (HepG2, HepG3, HepG4, Hep3B, H-4, Jurkat, Molt4, H-9, KHos24Os, A-431, U937, Mono Mac 6 and Raji) and from primary cultures of peripheral blood monocytes, fibroblasts and human umbilical vein endothelial cells (HUVEC) were investigated for the expression of factor-H mRNA. In RNA preparations from extrahepatic tissue, factor-H mRNA was only detected in biopsies from the lung. Using 20 micrograms total RNA isolated from all 13 cell lines it was not possible to detect any factor-H mRNA, while mRNA for factor H was expressed in monocytes, HUVEC and fibroblasts. When expressed in extrahepatic tissues, only the 4.3-kb and the 1.8-kb mRNA species were detected, while the 1.4-kb mRNA is expressed abundantly in liver. Interferon-gamma did not induce the expression of factor-H mRNA in any of the cell lines tested. On the other hand, tumour necrosis factor-alpha induced the expression of the 4.3-kb mRNA species in U937 cells. In HUVEC and fibroblasts the relative quantities of the 4.3-kb and the 1.8-kb mRNA species and the regulatory effects of interferon-gamma, interleukin-1, dexamethasone and retinoic acid on their expression showed significant tissue specificity.
Schwaeble
W
W
Institut für Hygiene, Innsbruck, Austria.
Schwaiger
H
H
Brooimans
R A
RA
Barbieri
A
A
Möst
J
J
Hirsch-Kauffmann
M
M
Tiefenthaler
M
M
Lappin
D F
DF
Daha
M R
MR
Whaley
K
K
D015152:Blotting, Northern; D002460:Cell Line; D003180:Complement C3b Inactivator Proteins / Q000235:genetics*; D017242:Complement Factor H; D015342:DNA Probes; D003907:Dexamethasone / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D009000:Monocytes / Q000502:physiology; D009928:Organ Specificity; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000494:pharmacology; D014212:Tretinoin / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
C493495:CFH protein, human; D003180:Complement C3b Inactivator Proteins; D015342:DNA Probes; D007375:Interleukin-1; D012333:RNA, Messenger; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D014212:Tretinoin; D003907:Dexamethasone; D017242:Complement Factor H; D007371:Interferon-gamma