Summary of the histological scores.

<p>Summary of the histological scores.</p

A comparative study of the characterization of miR-155 in knockout mice

<div><p>miR-155 is one of the most important miRNAs and plays a very important role in numerous biological processes. However, few studies have characterized this miRNA in mice under normal physiological conditions. We aimed to characterize miR-155 in vivo by using a comparative analysis. In our study, we compared miR-155 knockout (KO) mice with C57BL/6 wild type (WT) mice in order to characterize miR-155 in mice under normal physiological conditions using many evaluation methods, including a reproductive performance analysis, growth curve, ultrasonic estimation, haematological examination, and histopathological analysis. These analyses showed no significant differences between groups in the main evaluation indices. The growth and development were nearly normal for all mice and did not differ between the control and model groups. Using a comparative analysis and a summary of related studies published in recent years, we found that miR-155 was not essential for normal physiological processes in 8-week-old mice. miR-155 deficiency did not affect the development and growth of naturally ageing mice during the 42 days after birth. Thus, studying the complex biological functions of miR-155 requires the further use of KO mouse models.</p></div

Abdominal ultrasound parameter data.

<p>Abdominal ultrasound parameter data.</p

Changes in body weight.

<p>Changes in body weight.</p

Blood physiological values of the control and model groups.

<p>Blood physiological values of the control and model groups.</p

Representative echocardiography parameters.

<p>Cardiac functions were evaluated by echocardiography. (A and B) Length of the left ventricular outflow tract (LVOT); (C and D) Measurement and recording of the left ventricular short axis view; (E and F) Ventricular diastolic function detection: the ratio of the peak E and A wave velocities of the mitral valve rheography (E/A); and (G and H) IVS depth. The parameters showed no significant differences in the main evaluation indices. (Mice were 8 weeks old.).</p

Summary of reproductive performance.

<p>Summary of reproductive performance.</p

Representative photomicrographs of the vital organs.

<p>Sections fixed with paraformaldehyde were stained with haematoxylin and eosin (HE). Slides were observed with a light microscope (200×), and representative photomicrographs of sections of (A and B) lungs, (C and D) hearts, (E and F) livers, and (G and H) spleens from both the model and control groups are shown. No significant differences were observed for any of the evaluation indices. (Mice were 8 weeks old.).</p

Serum biochemical values of the control and model groups.

<p>Serum biochemical values of the control and model groups.</p

Summary of pertinent miR-155(-/-) mouse modelling studies.

<p>Summary of pertinent miR-155(-/-) mouse modelling studies.</p