![Figure 1. Efficient deletion of β1 integrin in the hematopoietic system does not affect cellularity of lymphoid organs. (A) Bone marrow of mice with a conditional knockout of β1 integrin, an Mx-cre transgene, and a constitutive knockout of β7 integrin (β1fl/–β7–/–Mx cre) was transplanted into lethally irradiated wild-type host mice. In bone marrow chimeras, donor and host cells could be distinguished by expression of Ly-5.1/Ly-5.2 surface marker. After repopulation of the hematopoietic system (4 weeks), polyIC was injected to induce expression of the cre recombinase in the donor cells and deletion of the β1 integrin gene. (B) Percentages of β1 integrin–negative platelets isolated from control and β1β7 mutant BM chimeric mice are shown at indicated time points after the first of 3 polyIC injections (day 0). Error bars show the standard deviation (n [control BM chimera]/[β1β7 mutant BM chimera]: 9/6). (C) DNA was isolated from single-cell suspensions from BM, thymus, and spleen from β1β7 mutant BM chimeras 10 months after polyIC treatment. Southern blot analysis detecting the conditional and the null allele was performed (a representative result is shown on the right panel). Band intensities were quantified and visualized in a bar graph. Error bars show the standard deviation. (n [control BM chimera]/[β1β7 mutant BM chimera]: 3/3). (D) Left panel: Single-cell suspensions were made from BM (2 femurs), thymus, spleen, and lymph nodes (2 inguinal, 2 axial, 1 para-aortic) of control and β1β7 mutant BM chimeric mice 2 months after the gene deletion. Cells were counted using a hemacytometer. The bar graph shows the absolute cell number in the respective tissues. Error bars show the standard deviation (n [control BM chimera]/[β1β7 mutant BM chimera]: 4/4). Right panel: Whole blood was collected retro-orbitally from control and β1β7 mutant BM chimeric mice 6 months after the gene deletion. The blood was diluted 1:10 with Türk stain and differentially counted in a hemacytometer. The bar graph shows the concentration of mononuclear (M) and polymorphonuclear (PMN) cells in the blood. Error bars show the standard deviation (n [control BM chimera]/[β1β7 mutant BM chimera]: 4/4).](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/108/6/10.1182_blood-2005-10-007658/4/zh80180601020001.jpeg?Expires=1723413450&Signature=3neG280Zm8GYPGPsRVqSh6F2-zFo2Ojqv005~ZIvMrn0UUIQJE1mSxNAYDOWk8cxCHyURhHt54t8E8ffV2dMb7jhRct3IV3c9~wjTeEJionr51006NNW9aomEjT1SIRrn1nNkADlv9XFPmkNf9i~67uafykQ7jAZvP0N5zuzs6~pANLNt7sckkloONPxqteLT13kQgF5RJUiIiiW-I1HcT42SNauBI7yFbFe0nC9yLTZIQrHa41ur4tboHk18plhdnQooztkMhtaJcElLyj8Z2b3Qih56a7EGHObRK8JwVLjQusIs3vWN4Y20RtdS~nDo~LqKlBXmO9HoqIAnNpsjA__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Efficient deletion of β1 integrin in the hematopoietic system does not affect cellularity of lymphoid organs. (A) Bone marrow of mice with a conditional knockout of β1 integrin, an Mx-cre transgene, and a constitutive knockout of β7 integrin (β1fl/–β7–/–Mx cre) was transplanted into lethally irradiated wild-type host mice. In bone marrow chimeras, donor and host cells could be distinguished by expression of Ly-5.1/Ly-5.2 surface marker. After repopulation of the hematopoietic system (4 weeks), polyIC was injected to induce expression of the cre recombinase in the donor cells and deletion of the β1 integrin gene. (B) Percentages of β1 integrin–negative platelets isolated from control and β1β7 mutant BM chimeric mice are shown at indicated time points after the first of 3 polyIC injections (day 0). Error bars show the standard deviation (n [control BM chimera]/[β1β7 mutant BM chimera]: 9/6). (C) DNA was isolated from single-cell suspensions from BM, thymus, and spleen from β1β7 mutant BM chimeras 10 months after polyIC treatment. Southern blot analysis detecting the conditional and the null allele was performed (a representative result is shown on the right panel). Band intensities were quantified and visualized in a bar graph. Error bars show the standard deviation. (n [control BM chimera]/[β1β7 mutant BM chimera]: 3/3). (D) Left panel: Single-cell suspensions were made from BM (2 femurs), thymus, spleen, and lymph nodes (2 inguinal, 2 axial, 1 para-aortic) of control and β1β7 mutant BM chimeric mice 2 months after the gene deletion. Cells were counted using a hemacytometer. The bar graph shows the absolute cell number in the respective tissues. Error bars show the standard deviation (n [control BM chimera]/[β1β7 mutant BM chimera]: 4/4). Right panel: Whole blood was collected retro-orbitally from control and β1β7 mutant BM chimeric mice 6 months after the gene deletion. The blood was diluted 1:10 with Türk stain and differentially counted in a hemacytometer. The bar graph shows the concentration of mononuclear (M) and polymorphonuclear (PMN) cells in the blood. Error bars show the standard deviation (n [control BM chimera]/[β1β7 mutant BM chimera]: 4/4).
