NOV 17, 2016 1:03 PM PST

Antiphospholipid Syndrome may be Triggered by gut Bacteria

WRITTEN BY: Carmen Leitch
Researchers studying antiphospholipid syndrome (APS) found that patients with the disease have high levels of bacteria that make phospholipids.  It has been previously established that antiphospholipid antibodies have pathogenic roles, so the scientists decided to assay fecal samples of patients with the disease to look for a source of the perpetual stimulation of those antibodies. Their findings indicate that microbes are a likely cause of APS, a life-threatening condition. To know more about APS, watch the following video.
 


APS is an autoimmune disease that primarily affects young women. There are antiphospholipid antibodies in those suffering from deep vein thrombosis, as well as in those who have experienced a stroke while under the age of 50. The antibodies are also a cause of complications during pregnancy and recurrent miscarriages.

"Transient antiphospholipid antibodies have long been associated with infections, but are not considered disease-related," said Martin A. Kriegel, MD, PhD, Assistant Professor of Immunology and Medicine and the study's lead author. "We hypothesized that commensals (microbes that normally reside in the gut) that chronically colonize us, instead of acute infections that resolve over time, might be the persistent triggers of APS in patients."

The cause of APS is not yet known, and blood thinners are the only treatment option, used to target the blood clots that appear in the final stage of disease, explained Kriegel. In this work, presented this week at the American College of Rheumatology Annual Scientific Meeting in Washington, the researchers wanted to investigate early triggers of the disease in an effort to prevent strokes and miscarriages.

"There's still significant mortality associated with this syndrome compared to other rheumatic diseases in which we can largely prevent mortality nowadays. So there is a huge need to better understand and treat this syndrome," Kriegel said.

For this study, the following were collected: 60 stool samples of 22 APS patients, 13 samples of six control subjects with thrombophilic (likely to form blood clots) and non-autoimmune states. For comparison, 49 samples of 19 healthy donors, each at baseline, at four and eight weeks, were sampled.

Peripheral blood mononuclear cells (PBMCs) from the APS patients responded preferentially to β2-glycoprotein I (GPI), a major auto-antigen in APS, compared to the controls. An assay of the fecal microbiomes of APS patients indicated an increase in Slackia bacteria, which can make phospholipids, and a decrease in Bilophilia bacteria. Those altered bacteria levels correlated with the production of antibodies.

"The study's findings are early, but suggest that certain gut microbes are enriched across time in APS patients compared to control subjects. Since we performed not only a cross-sectional microbiome study, but sampled our patients at thee monthly time points and tested how much microbes are coated with IgA antibodies from the patients, we believe that the gut microbes we identified as promising candidates should be studied further," said Kriegel. "These eventually may become biomarkers of disease or even treatment targets, but we're still far away from these goals."

"The immediate next step is to culture the candidate bacteria that emerged from the study and put them together with immune cells from the patients," he said. "In particular, we would like to test if cardiolipin could be derived from our candidate bacteria and, therefore, be recognized by the patients' immune cells that are known to target these lipids," concluded Kriegel.

Read more about APS here.

Sources: Lupus, AAAS/Eurekalert! via American College of Rheumatology
 
About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
SEP 11, 2020
Microbiology
Bat Ticks Are Discovered in New Jersey
SEP 11, 2020
Bat Ticks Are Discovered in New Jersey
While only about 25 of 900 species of tick spread disease, ticks are responsible for an estimated 95 percent of vector-b ...
SEP 22, 2020
Cardiology
Mosquito-Borne Illnesses are Linked to Stroke
SEP 22, 2020
Mosquito-Borne Illnesses are Linked to Stroke
Mosquitoes are major disease vectors; they are considered the world's deadliest animal because they kill so many people.
OCT 04, 2020
Microbiology
A Virus Can Disrupt a Carb-Consuming Gut Microbe
OCT 04, 2020
A Virus Can Disrupt a Carb-Consuming Gut Microbe
Not all viruses affect animal cells; some viruses can infect bacteria. Humans are known to carry vast numbers of microor ...
OCT 06, 2020
Microbiology
Scarlet Fever 'Superclones' Pose Rising Public Health Threat
OCT 06, 2020
Scarlet Fever 'Superclones' Pose Rising Public Health Threat
More than 100 years ago, the world faced waves of scarlet fever epidemics; between around 1820 and 1880 there were sever ...
NOV 17, 2020
Immunology
6 Injections a Year Prevent HIV Infections
NOV 17, 2020
6 Injections a Year Prevent HIV Infections
Last year, around 1.7 million people became infected with HIV, with around half of these being women. Encouraging result ...
NOV 16, 2020
Genetics & Genomics
Hidden Genes in the SARS-CoV-2 Genome
NOV 16, 2020
Hidden Genes in the SARS-CoV-2 Genome
It's essential for organisms to use their genomes to make proteins, and the processes of transcription and translation a ...
Loading Comments...