Related Experiment Video
Updated: Jul 2, 2026
07:52
Conjunctival Commensal Isolation and Identification in Mice
Published on: May 1, 2021
4.7K
Identification of an intraocular microbiota.
Yuhua Deng1, Xiaofei Ge1, Yan Li1
1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China.
Cell Discovery
|March 22, 2021
Summary
The human eye harbors bacteria, challenging the sterile environment dogma. This intraocular microbiome may be linked to eye diseases like macular degeneration and glaucoma.
Area of Science:
- Ophthalmology
- Microbiology
- Microbiome Research
Background:
- The prevailing view in ophthalmology considers the intraocular environment sterile.
- Emerging evidence suggests bacterial translocation from the gut to internal organs, including the eyes, in animal models.
- This raises the possibility of a microbial community within the human eye.
Purpose of the Study:
- To investigate the presence and nature of a microbial community within human intraocular samples.
- To determine if intraocular bacteria are associated with specific eye diseases.
- To explore the characteristics of the intraocular microbiome in non-human mammals.
Main Methods:
- Analysis of over 1000 human intraocular samples using quantitative PCR, transmission electron microscopy, and direct culture.
- Application of high-throughput sequencing technologies to identify microbial communities.
- Rigorous evaluation to exclude contamination from external sources.
Main Results:
- Demonstrated the presence of intraocular bacteria in human eyes, refuting the sterile environment assumption.
- Identified distinct microbial signatures in patients with age-related macular degeneration and glaucoma.
- Confirmed the existence of an intraocular microbiome in various mammalian species, varying by species and developing postnatally.
Conclusions:
- The human eye is not sterile and contains a distinct intraocular microbiome.
- The intraocular microbiome may play a role in the pathogenesis of common sight-threatening conditions.
- Comparative analysis in mammals provides insights into the establishment and variation of ocular microbiota.
More Related Videos
07:24Intravitreal Injection and Quantitation of Infection Parameters in a Mouse Model of Bacterial Endophthalmitis
Published on: February 6, 2021
12.1K
09:31Visualization of Gut Microbiota-host Interactions via Fluorescence In Situ Hybridization, Lectin Staining, and Imaging
Published on: July 9, 2021
9.0K
Related Concept Videos
01:22Introduction to the Human Microbiota
Microorganisms colonize various regions of the human body, including the mouth, nasal passages, throat, stomach, intestines, urogenital tract, and skin. The total number of microbial cells is estimated to range from 10¹³ to 10¹⁴—comparable to, or exceeding, the number of human somatic cells. This host–microbiome relationship has led to the conceptualization of humans as supraorganisms, wherein microbial communities perform vital roles in development, immunity, and disease...
01:27The Skin Microbiota
The human skin serves as a complex ecosystem inhabited by a diverse community of microorganisms, including bacteria, fungi, and viruses. This microbiome plays a critical role in maintaining skin health and defending against pathogenic invaders. The composition of microbial communities varies significantly across different regions of the body, influenced primarily by the local levels of moisture and sebum.Regional Variation in Skin MicrobiotaCutibacterium acnes predominantly colonizes sebaceous...
01:22Microbiome of the Eye
The human eye has a specialized microbiota that reflects its unique anatomical and immunological environment. This low-biomass microbial community predominantly colonizes the conjunctiva and eyelid margins, playing a vital role in ocular surface homeostasis and defense. Despite its proximity to the richly colonized facial skin, the ocular surface maintains a distinct microbial profile due to continuous mechanical and biochemical defense mechanisms.The conjunctival surface hosts fewer microbial...
01:29Microbiota of the Respiratory Tract
The human respiratory tract, comprising the upper and lower segments, serves as a critical interface with the external environment. The upper respiratory tract (URT)—including the nostrils, sinuses, pharynx, and oropharynx—is heavily colonized by microbes, while the lower respiratory tract (LRT), composed of the larynx, trachea, bronchi, and lungs, was long thought to be sterile. However, recent molecular studies have revealed that the lungs are not devoid of microbes but act more like...
01:27Microbiota of the Large Intestine
The large intestine hosts the most densely populated microbial ecosystem in the human body. This complex community primarily consists of anaerobic bacteria, with Bacillota (formerly Firmicutes) and Bacteroidota (formerly Bacteroidetes) as the predominant groups. The distribution of these microbes varies along different sections of the large intestine, influenced by local environmental factors such as oxygen availability and nutrient composition.The cecum, located at the beginning of the large...
01:28Microbiota of the Urogenital Tract
The human urogenital system, once thought to be sterile in healthy individuals, is now recognized as a complex microbial habitat. Advancements in molecular sequencing techniques have revealed that even in healthy adults, the kidneys and bladder harbor microbial populations similar to those found in the distal urethra, albeit in much lower abundance. These resident microorganisms, while generally innocuous, can become opportunistic pathogens under conditions that alter the urogenital...