Found this in JAMA:

I need Elizabeth to fully understand it, but I think the matrix
metalloproteinases are somehow related to biofilms. Interesting use of
an antibiotic to treat an auto immune condition:

Combination therapy with interferon beta-1a and doxycycline in
multiple sclerosis: an open-label trial.

Minagar A, Alexander JS, Schwendimann RN, Kelley RE, Gonzalez-Toledo
E, Jimenez JJ, Mauro L, Jy W, Smith SJ.
Department of Neurology, Louisiana State University Health Sciences
Center, 1501 Kings Highway, Shreveport, LA 71130, USA.
aminag@lsuhsc.edu
OBJECTIVE: To evaluate the efficacy, safety, and tolerability of
combination therapy with intramuscular interferon beta-1a and oral
doxycycline, a potent inhibitor of matrix metalloproteinases, in
patients with relapsing-remitting multiple sclerosis (RRMS) having
breakthrough disease activity. DESIGN: Open-label, 7-month trial.
SETTING: Louisiana State University Health Sciences Center,
Shreveport. PATIENTS: Fifteen patients with RRMS taking interferon
beta-1a with breakthrough disease activity took doxycycline for 4
months. Patients underwent monthly neurologic examination, magnetic
resonance imaging of the brain using triple-dose gadolinium, and
safety blood work. INTERVENTIONS: Ongoing treatment with intramuscular
interferon beta-1a plus oral doxycycline, 100 mg daily, for 4 months.
MAIN OUTCOME MEASURES: The primary end point was gadolinium-enhancing
lesion number change, and the secondary end points were relapse rates,
safety and tolerability of the combination of interferon beta-1a and
doxycycline in patients with MS, Expanded Disability Status Scale
score, serum matrix metalloproteinase-9 levels, and transendothelial
migration of monocytes exposed to serum from patients with RRMS.
RESULTS: Combination of doxycycline and interferon beta-1a treatment
resulted in reductions in contrast-enhancing lesion numbers and
posttreatment Expanded Disability Status Scale values (P < .001 for
both). Only 1 patient relapsed. Multivariate analyses indicated
correlations between decreased serum matrix metalloproteinase-9 levels
and enhancing lesion activity reduction. Transendothelial migration of
monocytes incubated with serum from patients with RRMS undergoing
combination therapy was suppressed. Adverse effects were mild; no
adverse synergistic effects of combination therapy or unexpected
adverse events were reported. CONCLUSIONS: Combination of
intramuscular interferon beta-1a and oral doxycycline treatment was
effective, safe, and well tolerated. Controlled clinical trials in
larger cohorts of patients with MS are needed to evaluate the efficacy
and tolerability of this combination

http://www.ncbi.nlm.nih.gov/pubmed/18071030?ordinalpos=4&itool=EntrezSystem2.PEn
trez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

Judy