Role of serum soluble Fas receptors (APO-1, CD95)‎ in some rheumatic diseases

Abstract EN

Serum soluble Fas Apo-1 was measured in the sera of 49 patients: 20 with rheumatoid arthritis, 16 with SLE and 13 with systemic sclerosis.

This was compared to the level in the sera of ten apparently healthy individuals matched for age and sex.

For all patients, careful history taking and thorough clinical examination for manifestations of different rheumatic diseases were done.

Immunological investigations were done namely RF and ANA for suspected cases of RA, ANA and anti-double stranded DNA antibodies for suspected cases of SLE and anticentromere antibodies and anti-Scl 70 antibodies for suspected cases of SSc.

The level of serum soluble Fas receptors was measured for all groups using the sandwich ELISA kit.

All the sixteen cases with SLE were females with a mean age of 27.8 ± 11.0.

The cases of SSc were 3 males and 10 females with a mean age of 39.1 ± 4.9.

Cases with RA were 3 males and 17 females with a mean age of 46.9 ± 5.4.

Serum soluble Fas receptors level was statistically significantly increased in cases of SLE as compared to controls (p < 0.05).

It was also increased in cases of RA but with no statistical significance (p > 0.05).

In SSc, there was no difference as compared to controls (p > 0.05).

Comparing the level of sFas receptors among the different groups, there was a high statistical significant increase in cases of SLE versus SSc (p < 0.01), a statistical significant increase in cases of RA versus SSc (p < 0.05), but comparing the sFas level in cases of RA to SLE, no statistical difference was observed (p > 0.05).

The relationship between the presence and absence of different clinical, laboratory and X-ray findings in different groups and the level of sFas receptors was assessed.

In cases of SLE, sFas levels were significantly lower in patients with skin rash and higher in cases with positive anti-dsDNA antibodies.

The level of sFas was higher in those with CNS and renal affection but it did not reach statistical significant values.

Using Spearman correlation, there was a significant positive correlation between sFas and SLEDAI score (r = 0.875).

In RA, patients with positive RF and those with erosive Xray changes had a statistical significant increase in sFas level than those who did not.

There was no statistical significant difference in comparing the level of sFas and any of the clinical, laboratory or X-ray findings in cases of SSc.

In conclusion, serum sFas receptors might have an important role in the pathogenesis and might serve as an indicator of disease activity in SLE.

In RA, their level can reflect the severity of joint destruction.

A further study is needed to compare synovial fluid level and serum level of sFas receptors in cases of RA.

As regards SSc, another study with larger number of cases is needed to determine the role of sFas receptors in such cases.