All
  • All
  • Insight
  • Research Services
  • Preclinical CRO
  • Animal Resource Bank
CN
中文 English
Latest News

Latest News

Focusing on cutting-edge technologies and research advancements,
sharing Aniphe BioLab’s achievements in scientific innovation, Professional insights
and practical experience in the fields of laboratory animals and preclinical research.

Key Insights | Pathological Analysis of Partially Stained Specimens

Introduction:

Pathological analysis investigates the disease processes occurring in organs, tissues, or cells, examining the etiology, pathogenesis, and the course of lesion development, ultimately leading to a pathological diagnosis.

In this issue, we’ll walk you through the pathological analysis of selected staining techniques.

 

 

Pathomorphological examination methods ： First, examine the gross pathological changes of the specimen; then, excise a tissue sample of appropriate size, prepare a histopathological section using standard histological techniques, and further evaluate the lesion under a microscope or perform whole‑slide scanning.

Pathomorphological description by Aniphe BioLab: 50 yuan per slide.

For different tissue conditions, staining is used to assess pathological changes by comparing the staining patterns of the control and experimental groups; additionally, software can be employed to quantify the area fraction of the affected tissue (the stained region).

 

 

Hematoxylin–Eosin staining (H&E staining)

Hematoxylin–eosin (HE) staining is one of the most commonly used techniques in paraffin‑section histology. Hematoxylin, an alkaline dye, stains nuclear chromatin and cytoplasmic nucleic acids a purplish‑blue color; eosin, an acidic dye, imparts a red hue to cytoplasmic components and extracellular matrix constituents. HE staining is the most fundamental and widely employed method in teaching and research across histology, embryology, and pathology.

Aniphe BioLab HE Staining Test: 7 yuan per slide

HE staining of the liver in normal mice

Human thyroid carcinoma xenograft in nude mice

 

As shown in the figure, the tumor cells in the control group exhibit diffuse growth, with a dense and disorganized arrangement and no discernible tissue architecture. The cancer cells have abundant cytoplasm, nuclei that overlap one another, and marked nuclear atypia; typical pathological mitotic figures are also observed, consistent with the features of papillary thyroid carcinoma.

In the experimental group, the transplanted tumors exhibited a reduced cellular density, with pale cytoplasm, lightly stained nuclei, small nucleoli, and diminished mitotic activity. The nucleus-to-cytoplasm ratio was decreased, and some cells showed nuclear pyknosis, karyolysis, cellular disintegration, and loss of tissue architecture.

 

As shown in the figure, the number of neuronal cells in the brain tissue of rats in the heatstroke model group was lower than that in the blank control group; in the drug‑treatment group, the number of neuronal cells was higher than in the heatstroke model group.

By comparing with the blank/control group, observe changes in cell morphology, as well as alterations in the nucleus or cytoplasm.

 

 

Masson’s trichrome stain (Masson staining)

Masson’s trichrome stain is a method for staining connective tissue, commonly used to examine the proliferation and distribution of fibrous connective tissue in pathological tissues. Collagen fibers serve as a cushioning structure, protecting the surrounding blood vessels and nerves. Collagen fiber hyperplasia typically arises in response to local skin inflammation or tissue overgrowth.

The staining results show collagen fibers as blue, muscle fibers as red, and nuclei as bluish-black.

Aniphe BioLab Masson’s Trichrome Staining Test: 15 yuan per slide

Masson’s trichrome staining of the kidney in normal rats

The figure shows staining of the kidneys from a normal rat; we are required to examine the following parameters:

(1) Observation of organ sclerotic diseases: For example, in the case of hepatic cirrhosis and myocardial scarring, collagen staining facilitates more accurate observation and diagnosis.

(2) Differentiation between scars and amyloid deposits: collagen fibers stain positive in the former, whereas they are negative in the latter.

(3) Differentiation between fibrous dysplasia and fibrosis: Collagen fiber staining facilitates the visualization of disorganized, interwoven collagen fibers in the former, whereas the latter exhibits a more regular arrangement.

As shown in the figure, under light microscopy, the tunica albuginea of a normal canine testis exhibits prominent collagen fibers (Fig. D); in cryptorchid testes, the seminiferous tubule walls are folded, and the collagen fibers in the tubular walls are markedly thickened compared with those in normal testes (Fig. E); in testicular tumors, collagen fiber proliferation is observed locally (Fig. F).

Masson’s trichrome staining can be used to visualize the distribution of collagen and muscle fibers, and software can be employed for the semi-quantitative analysis of collagen fiber content.

Following treatment, the experimental group exhibited a fine reticular distribution of blue collagen fibers, whereas the control group showed a lamellar arrangement of collagen fibers. Collagen deposition was significantly greater in the control group than in the experimental group. Using ImageJ software to quantify collagen content in the tissues, the experimental group demonstrated a markedly lower collagen content compared with the control group, with a statistically significant difference between the two groups (p < 0.05).

These findings indicate that treatment in the experimental group can reduce the collagen fiber content in tumor tissue, thereby decreasing the distance and resistance to drug delivery and enabling more of the drug to reach tumor cells located far from the vasculature, thus enhancing the efficacy of chemotherapy.

 

Oil Red O staining

Because Oil Red O is a lipophilic dye that dissolves readily in lipids, it specifically stains neutral lipids such as triglycerides in tissues red. Since lipids are readily soluble in organic solvents, Oil Red O staining requires the use of fresh frozen sections.

Oil Red O staining is primarily used to visualize fatty degeneration and abnormal lipid deposition in tissues and organs. Such conditions frequently occur as fatty degeneration in parenchymal organs such as the liver, kidneys, and heart.

Aniphe BioLab Oil Red O Staining Test: 15 yuan per slide

Fatty liver, Oil Red O staining

The figure shows Oil Red O–stained sections of atherosclerotic mice and control mice. As can be seen, the aortic atherosclerotic plaque area in the atherosclerosis (AS) model group was significantly larger than that in the normal control group. Compared with the model group, treatment with Sal B or ATO markedly reduced plaque area (p<0.05). In the control mice, hepatic tissue architecture was normal and well‑defined; by contrast, MOD mice exhibited disorganized liver architecture, with foci of inflammatory cell infiltration and ballooning steatosis. Compared with the MOD group, the Sal B– and ATO‑treated mice showed significant amelioration of hepatic histopathological changes.

 

Oil Red O staining can be used to visualize the distribution of lipids, and software can be employed for semi-quantitative analysis of lipid content.

 

General Analytical Methods

1. When conducting pathological analysis, a control group is required, and the experimental group should be compared with the control group.

2. Determine an appropriate staining method based on the research objectives.

3. Perform semi-quantitative analysis using software.

 

Quantitative Analysis

 

 

References:

[1] Cheng Ran, Wei Feng, Zhang Yuan, et al. Study on the inhibitory effect of 5-azadeoxyuridine on human thyroid cancer xenografts in nude mice and its underlying mechanism [J]. Tianjin Medicine, 2022, 50(5):476–481. DOI:10.11958/20212422.

[2] Wang Linan, Wang Hong, Shi Qian, et al. Mechanism of the protective effect of urinary trypsin inhibitor on neurological damage in rats with heatstroke [J]. Journal of Trauma and Critical Care Medicine, 2022, 10(2): 83–87. DOI: 10.16048/j.issn.2095-5561.2022.02.02.

[3] Ren Jianming, Wei Yanming, Yuan Ligang, et al. Comparative distribution of PGP9.5 and NPY in cryptorchidism and testicular tumors in dogs [J]. Chinese Journal of Animal Husbandry & Veterinary Medicine, 2020, 47(9): 2741–2750. DOI: 10.16431/j.cnki.1671-7236.2020.09.006.

[4] Zhang Shiyu. Study on the Enhancement of Chemotherapy Efficacy through Oxygen-Carrying Fluorocarbon Nanodroplets Combined with Ultrasound-Induced Tumor Vasculature Normalization [D]. Guangdong: Southern Medical University, 2020.

[5] Zhang Yifan, Han Xianghui, Liu Ping. Salvianolic Acid B attenuates hepatic inflammation in an atherosclerosis mouse model by inhibiting the MAPKs/NF-κB signaling pathway [J]. Chinese Pharmacological Bulletin, 2022, 38(4): 525–530. DOI: 10.12360/CPB202108008.

 

For more professional, cutting-edge, and engaging scientific insights, look no further than Aniphe BioLab!

 

Organizer  |  Aniphe BioLab Marketing Department

Supervising Producer  |  Solar wind

Editor-in-chief  |  Lemon

Submission  |  Always

Editor-in-chief  |  Swallow

Editor  |  Lemon

 

 

 

PREVIOUS:

Key Insights | What Are the Animal Models of Rheumatoid Arthritis?

NEXT:

Key Insights | Tumor Models: Growth, Metastasis, and Recurrence Models