Fabry M E, Sengupta A, Suzuka S M, Costantini F, Rubin E M, Hofrichter J, Christoph G, Manci E, Culberson D, Factor S M, Nagel R L
Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Blood. 1995 Sep 15;86(6):2419-28.
We report on a second generation of transgenic mice produced by crossing a transgenic mouse line expressing high levels of human alpha and beta S chains (alpha H beta S [beta MDD]) with a line expressing human alpha and beta S-Antilles (beta SAnt). We hypothesized that mice expressing both hemoglobins (Hbs) would have a more severe phenotype because the reduced oxygen affinity and solubility of the beta S-Antilles might enhance the rate and extent of polymer formation. We obtained mice that expressed both beta S and beta S-Antilles. The doubly transgenic mice that are heterozygous for deletion of mouse beta Major (beta MD) occurred with reduced frequency and those that are homozygous for deletion of mouse beta Major (beta MDD) occurred at a much reduced frequency and suffered early mortality. Human alpha was 58% of all alpha globin for all animals, whereas beta S and beta S-Antilles were 34% and 28% of all beta globins for beta MD mice and 42% and 36% for beta MDD mice. Hematocrit, Hb, and mean corpuscular Hb were normal for all transgenic mice, but reticulocyte levels were higher for the doubly transgenic mice versus alpha H beta S [beta MDD] mice older than 30 days (10.0% +/- 1.0% v 4.3% +/- 0.4%; P < .001, mean +/- SE, n = 20 and n = 10, respectively) and control mice (3.9% +/- 0.4%). Reticulocytosis was more severe in mice less than 30 days old ( > 20% for alpha H beta S beta S-Ant[beta MDD] mice). The median mean corpuscular hemoglobin concentration of doubly transgenic mice was higher than that of alpha H beta S[beta MDD] mice with a variable number of very dense cells. Delay times for polymerization of Hb in red blood cells from alpha H beta S beta S-Ant[beta MDD] mice were shorter than those of alpha H beta S[beta MDD] mice, and there were fewer cells with delay times greater than 100 seconds. Urine-concentrating ability in control mice under ambient conditions is 2,846 +/- 294 mOsm and was reduced 30% to 1,958 +/- 240 mOsm, P < 4 x 10(-8) in all mice expressing both transgenes. We conclude that doubly transgenic mice have a more severe phenotype than either of the two parental lines. These mice may be suitable for validating therapeutic intervention in sickle cell disease.
我们报告了第二代转基因小鼠，它是通过将一个表达高水平人α和β S链（αHβS[βMDD]）的转基因小鼠品系与一个表达人α和β S-安的列斯（βSAnt）的品系杂交产生的。我们推测，表达两种血红蛋白（Hb）的小鼠会有更严重的表型，因为β S-安的列斯较低的氧亲和力和溶解度可能会提高聚合物形成的速率和程度。我们获得了表达β S和β S-安的列斯的小鼠。杂合缺失小鼠β主要（βMD）的双转基因小鼠出现频率降低，而纯合缺失小鼠β主要（βMDD）的双转基因小鼠出现频率大幅降低且早期死亡。对于所有动物，人α占所有α珠蛋白的58%，而对于βMD小鼠，β S和β S-安的列斯分别占所有β珠蛋白的34%和28%，对于βMDD小鼠则分别为42%和36%。所有转基因小鼠的血细胞比容、Hb和平均红细胞Hb均正常，但30天以上的双转基因小鼠的网织红细胞水平高于αHβS[βMDD]小鼠（分别为10.0%±1.0%对4.
