The effects of immune protein CD3ζ development and degeneration of retinal neurons after optic nerve injury

<div><p>Major histocompatibility complex (MHC) class I molecules and their receptors play fundamental roles in neuronal death during diseases. T-cell receptors (TCR) function as MHCI receptor on T-cells and both MHCI and a key component of TCR, CD3ζ, are expressed by mouse retinal ganglion cells (RGCs) and displaced amacrine cells. Mutation of these molecules compromises the development of RGCs. We investigated whether CD3ζ regulates the development and degeneration of amacrine cells after RGC death. Surprisingly, mutation of CD3ζ not only impairs the proper development of amacrine cells expressing CD3ζ but also those not expressing CD3ζ. In contrast to effects of MHCI and its receptor, PirB, on other neurons, mutation of CD3ζ has no effect on RGC death and starburst amacrine cells degeneration after optic nerve crush. Thus, unlike MHCI and PirB, CD3ζ regulates the development of RGCs and amacrine cells but not their degeneration after optic nerve crush.</p></div

RGC death after ONC is associated with quick dendritic reorganization of SACs/DSACs.

<p>(<b>A</b>) Optic nerve exposing and crushing. (<b>B</b>) An image of the longitude cross section of the proximal portion of the optic nerve and the posterior portion of the eye. RGCs and their axons are labeled with CTB conjugated with Alexa Fluor 594 (yellow) and the section was co-labeled with DAPI (red). Please note that the axonal transport of CTB along RGC axons is completely blocked at the crush site. (<b>C</b>) Magnification from whole mount retina of a mouse without ONC showing the density of DAPI stained nuclei in the GCL (C1, blue), the density of anti-ChAT stained DSACs (C2, red) and the overlay of the DAPI and anti-ChAT stainings (C3). (<b>D</b>) Magnification from whole mount retina of a mouse with ONC showing the density of DAPI stained nuclei in the GCL (D1, blue), the density of anti-ChAT stained DSACs (D2, red) and the overlay of the DAPI and anti-ChAT stainings (D3). (<b>E</b>) Representative maximum projection images of DSACs without (E1) and with (E2) ONC. (<b>F</b>) The tracing results of the DSACs shown in panel E.</p

Quantify dendritic structure of mouse SACs/DSACs.

<p>(<b>A</b>) Whole mount retina of a CreER-ChAT:Stop-YFP mouse stained with anti-GFP (green) and DAPI (blue). The four dashed-line boxes indicate the areas used for cell density calculation. (<b>B</b>) An enlarged area of the retinal ganglion cell layer showing YFP staining of Cre activated DSACs (green), anti-ChAT antibody staining of all DSACs (red) and DAPI (blue) staining of the GCL. (<b>C</b>) A cross section of the retina of a CreER-ChAT:Stop-YFP mouse showing YFP staining of Cre activated SACs and DSACs (green) and anti-ChAT antibody staining of SACs and DSACs (red) in the retina. (<b>D</b>) A maximum projection of the dendrites of a DSAC. (<b>E</b>) The tracing results of the DSAC shown in panel D (green, dendrites; red, soma; blue, dendritic field). (<b>F</b>) The dendrogram of the DSAC shown in panel D. The total length of dendrites, the number of dendritic branches, the order of each dendritic branch and the length of each dendritic branch were derived from this dendrogram. (<b>G</b>) Average size of dendritic field of SACs and DSACs. (<b>H</b>) Average length of dendrites of SACs and DSACs. (<b>I</b>) Average density of SACs and DSACs. (<b>J</b>) The number of dendritic branch as a function of dendritic order of SACs and DSACs. (<b>K</b>) The average number of dendritic branch of SACs and DSACs. (<b>L</b>) The length of dendritic branch as a function of dendritic order of SACs and DSACs. (<b>M</b>) The average length of dendritic branch of SACs and DSACs. The numbers in the columns of panels G, H, K and M indicate number of cells analyzed. The numbers in the columns of panel I indicate the numbers of images analyzed. In this figure and all following figures, * indicates 0.01</p

Mutation of CD3ζ impairs the development of SACs/DSACs.

<p>(<b>A</b>) Representative maximum projection images with the dendritic tracing of SACs and DSACs of WT and CD3ζ-/- mice. (<b>B</b>) A cross section of the retina of a WT mouse showing the co-labeling of ChAT (red) and CD3ζ (green) antibody staining (scale bar: 20μm). (<b>C</b>) A cross section of the retina a CD3ζ-/- mouse showing anti-ChAT antibody staining of SACs/DSACs (red) and DAPI (blue) staining of the retina (scale bar: 20μm). (<b>D</b>) Average size of the dendritic field of SACs and DSACs in both WT and CD3ζ-/- mice. (<b>E</b>) The total dendritic length of SACs and DSACs in both WT and CD3ζ-/- mice. (<b>F</b>) The average densities of DAPI stained nuclei of GCL in both WT and CD3ζ-/- mice. (<b>G</b>) The average densities of SACs in both WT and CD3ζ-/- mice. (<b>H</b>) The average densities of DSACs in both WT and CD3ζ-/- mice. The numbers in the columns of panels D-E indicate the number of cells analyzed. The numbers in the columns of panels F-H indicate the numbers of images analyzed.</p

Virtual reality method to analyze visual recognition in mice

<div><p>Behavioral tests have been extensively used to measure the visual function of mice. To determine how precisely mice perceive certain visual cues, it is necessary to have a quantifiable measurement of their behavioral responses. Recently, virtual reality tests have been utilized for a variety of purposes, from analyzing hippocampal cell functionality to identifying visual acuity. Despite the widespread use of these tests, the training requirement for the recognition of a variety of different visual targets, and the performance of the behavioral tests has not been thoroughly characterized. We have developed a virtual reality behavior testing approach that can essay a variety of different aspects of visual perception, including color/luminance and motion detection. When tested for the ability to detect a color/luminance target or a moving target, mice were able to discern the designated target after 9 days of continuous training. However, the quality of their performance is significantly affected by the complexity of the visual target, and their ability to navigate on a spherical treadmill. Importantly, mice retained memory of their visual recognition for at least three weeks after the end of their behavioral training.</p></div

Quantitative analysis of the dendritic structure of SACs/DSACs after ONC.

<p>(<b>A</b>) The average densities of DAPI stained nuclei of GCL of mice with and without ONC. (<b>B</b>) The average densities of anti-ChAT antibody stained SACs and DSACs before and after ONC. (<b>C</b>) Average total length of dendrites of SACs and DSACs of mice before and after ONC. (<b>D</b>) Average size of dendritic field of SACs and DSACs of mice before and after ONC. (<b>E</b>) The number of dendritic branch as a function of dendritic order of SACs before and 10 days after ONC. (<b>F</b>) The number of dendritic branch as a function of dendritic order of DSACs before and 10 days after ONC. (<b>G</b>) The length of dendritic branch as a function of dendritic order of SACs before and 10 days after ONC. (<b>H</b>) The length of dendritic branch as a function of dendritic order of DSACs before and 10 days after ONC. The numbers in the columns of panels A-B indicate number of images analyzed. The numbers in the columns of panels C-D indicate the numbers of cells analyzed.</p

Dopamine D1 receptors mediate the light-sensitive response gain of outer retina.

<p>The b-wave/a-wave ratios and OPs/b-waves ratios of WT and D1−/− mice raised under cyclic light/dark conditions and constant darkness were used to assess the effects of light deprivation on the response gains of ERG. <b>A:</b> The b-wave/a-wave ratios of WT mice raised under cyclic light/dark conditions and constant darkness were plotted as a function of the light intensity showing a significant increase of the outer retina response gain at the light intensities of 0.008–0.08 cd*s/m². <b>B:</b> The OPs/b-wave ratios of WT mice raised under cyclic light/dark conditions and constant darkness. <b>C:</b> The b-wave/a-wave ratios of D1−/− mice raised under cyclic light/dark conditions and constant darkness showing a significant decrease of the outer retina response gain at the light intensities of 0.08–0.25 cd*s/m². <b>D:</b> The OPs/b-wave ratios of D1−/− mice raised under cyclic light/dark conditions and constant darkness. <b>E:</b> The b-wave/a-wave ratios of D1−/− mice raised in constant dark were normalized to D1−/− mice raised in cyclic light/dark conditions while the b-wave/a-wave ratios of WT mice raised in constant dark were normalized to WT mice raised in cyclic light/dark conditions. The two normalized b-wave/a-wave curves were plotted as functions of light intensities and showed that light deprivation significantly increased the b-wave/a-wave ratios of light responses evoked by low light intensities in WT but not D1−/− mice. <b>F:</b> The OPs/b-wave ratios of D1−/− and WT mice raised in constant dark were normalized to control mice raised in cyclic light/dark conditions, respectively, and plotted as functions of light intensities.</p

Mutation of CD3ζ does not alter the dendritic reorganization of SACs/DSACs after ONC.

<p>(<b>A</b>) Magnification from whole mount retina of a CD3ζ-/- mouse without ONC showing the density of DAPI stained nuclei in the GCL (A1), the density of anti-ChAT stained DSACs (A2) and the overlay of the DAPI and anti-ChAT stainings (A3). (<b>B</b>) Magnification from whole mount retina of a CD3ζ-/- mouse with ONC showing the density of DAPI stained nuclei in the GCL (B1), the density of anti-ChAT stained DSACs (B2) and the overlay of the DAPI and anti-ChAT stainings (B3). (<b>C</b>) The densities of DAPI stained nuclei of GCL of WT and CD3ζ-/- mice before and 10 days after ONC. (<b>D</b>) The densities of SACs of WT and CD3ζ-/- mice before and 10 days after ONC. (<b>E</b>) The densities of DSACs of WT and CD3ζ-/- mice before and 10 days after ONC. (<b>F</b>) The size of dendritic field of SACs of WT and CD3ζ-/- mice before and 10 days after ONC. (<b>G</b>) The size of dendritic field of DSACs of WT and CD3ζ-/- mice before and 10 days after ONC. (<b>H</b>) The total length of dendrites of SACs of WT and CD3ζ-/- mice before and 10 days after ONC. (<b>I</b>) The total length of dendrites of DSACs of WT and CD3ζ-/- mice before and 10 days after ONC. The numbers in the columns of panels B-D indicate number of images analyzed. The numbers in the columns of panels E-H indicate the numbers of cells analyzed.</p

Light deprivation suppresses the OPs amplitudes of WT but not D1−/− mice.

<p>To determine the effects of light deprivation on ERG amplitudes, WT and D1−/− mice were raised in constant darkness from birth and the ERGs were recorded at P30. <b>A:</b> Average intensity-response curves of a-wave amplitude of WT mice raised in cyclic light/dark conditions (WT Light, 20 mice, 40 eyes) and constant darkness (WT Dark, 7 mice, 14 eyes). <b>B:</b> Average intensity-response curves of b-wave amplitude of WT mice raised in cyclic light/dark conditions and constant darkness. <b>C:</b> Average intensity-response curves of OPs of WT mice raised in cyclic light/dark conditions and constant darkness showing significant decrease of the OPs amplitudes of dark-reared mice. <b>D:</b> Average intensity-response curves of a-wave amplitude of D1−/− mice raised in cyclic light/dark conditions (D1−/− Light, 10 mice, 20 eyes) and constant darkness (D1−/− Dark, 6 mice, 12 eyes). <b>E:</b> Average intensity-response curves of b-wave amplitude of D1−/− mice raised in cyclic light/dark conditions and constant darkness. <b>F:</b> Average intensity-response curves of OPs of D1−/− mice raised in cyclic light/dark conditions and constant darkness showing no significant difference between the OPs amplitudes of dark-reared mice and mice raised under cyclic light/dark conditions.</p

D1−/− mice have selective increase of ERG b-wave amplitude at the time of eye opening.

<p>ERGs were recorded from dark-adapted WT and D1−/− mice at the age of P13. The amplitudes of a-wave, b-wave and OPs were plotted as a function of intensity of light stimuli and the amplitudes of ERG a-wave, b-wave and OPs of P13 WT and D1−/− mice were compared with that of P30 mice to reveal the developmental changes of ERG amplitudes. <b>A:</b> Average intensity-response curves of a-wave amplitude of WT (n = 12 eyes of 6 mice) and D1−/− (n = 12 eyes of 6 mice) mice. <b>B:</b> The P30/P13 ratios of ERG a-wave amplitudes of WT and D1−/− mice as a function of light intensity. <b>C:</b> Average intensity-response curves of b-wave amplitude of the same groups WT and D1−/− mice. <b>D:</b> The P30/P13 ratios of b-wave amplitudes of WT and D1−/− mice as a function of light intensity. <b>E:</b> Average intensity-response curves of OPs of WT and D1−/− mice. <b>F:</b> The P30/P13 ratios of OPs amplitudes of WT and D1−/− mice as a function of light intensity.</p