The advancement of tissue clearing technology has significantly propelled neuroscience research. Nevertheless, the fluorescent proteins used in traditional transgenic mouse strains were not specifically optimized for tissue clearing procedures, resulting in a substantial decrease in fluorescent intensity after clearing. In this study, we developed the Ci1 reporter mouse strain (where Ci stands for the Chinese Institute for Brain Research, CIBR) based on the bright red fluorescent protein mScarlet. The Ci1 reporter exhibits no fluorescence leakage in various organs or tissue types and can be readily crossed with multiple tissue-specific Cre lines. Compared to the Ai14 mouse strain, the Ci1 reporter strain demonstrates lower non-specific leakage, stronger fluorescence intensity in different tissues, and better preservation of fluorescence following tissue clearing treatment. The creation of the Ci1 reporter provides a more effective tool for both neuroscience and other biomedical research applications.
Animals ; Luminescent Proteins/metabolism* ; Mice, Transgenic ; Mice ; Red Fluorescent Protein ; Brain/metabolism* ; Genes, Reporter ; Fluorescence

A 58-yr-old man presented with leg edema and subacute weakness of his bilateral lower extremities. Urinary and serum immunoelectrophoresis revealed the presence of lambda-type Bence Jones proteins. He was ultimately diagnosed with monoclonal gammopathy of undetermined significance (MGUS). A renal biopsy specimen showed fibrillary glomerulonephritis (FGN), which was randomly arranged as 12-20 m nonbranching fibrils in the basement membranes. Immunofluorescence studies were negative for immunoglobulin (Ig)G, IgM, IgA, C3, and kappa light chains in the capillary walls and mesangial areas. A Congo red stain for amyloid was negative. Electromyography and nerve conduction velocity examinations results were compatible with the presence of demyelinating polyneuropathy. This case showed a rare combination of FGN, without Ig deposition, and MGUS combined with chronic inflammatory demyelinating polyneuropathy (CIDP).
Amyloid ; Basement Membrane ; Bence Jones Protein ; Biopsy ; Capillaries ; Congo Red ; Edema ; Electromyography ; Fluorescent Antibody Technique ; Glomerulonephritis* ; Immunoelectrophoresis ; Immunoglobulin A ; Immunoglobulin M ; Immunoglobulins ; Leg ; Lower Extremity ; Monoclonal Gammopathy of Undetermined Significance ; Neural Conduction ; Paraproteinemias ; Polyneuropathies*