I found this probiotic writing my post on Lactose Intolerance . There were some interesting characteristics of it, so I thought a deeper dive was warranted. It is also known as Lactobacillus acidophilus strain LA1.
- The effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance – a randomized, double-blind, placebo-controlled, crossover clinical trial . “The DDS-1 strain of Lactobacillus acidophilus, discovered in 1959 by Dr. Khem Shahani at the University of Nebraska, is a unique strain of L. acidophilus on deposit with the FDA Agricultural Research Service (ARS) with the catalog number B-3208. It is currently manufactured by Nebraska Cultures, Inc. A recent study demonstrated the DDS-1 strain of L. acidophilus to be superior to other strains of lactobacillus in the ability to establish in the human gastrointestinal (GI) tract …can provide symptom benefit compared with placebo among individuals who consume the product for a course of 4 weeks.”
- ” LA1 induced the production of higher levels of IL-1 alpha and TNF-alpha than other lactobacilli and bifidobacteria.”  Both IL-1 and TNF-alpha are HIGH with CFS so not a good choice.  
- “These results do not support a beneficial effect of Lactobacillus acidophilus strain DDS-1 and Bifidobacterium longum strain UABL-14 on plasma lipids” 
- “The administration of a probiotic mixture containing L. acidophilus DDS-1, B. lactis UABLA-12, and fructo-oligosaccharide was associated with significant clinical improvement in children with atopic dermatitis (AD), with corresponding lymphocyte subset changes in peripheral blood. The efficacy of probiotic therapy in adults with AD requires further investigation.” 
This “best of class” lactobacillus acidophilus is NOT what you want to take with CFS or any condition with high TNF-Alpha or IL-1. My ongoing advice to avoid all lactobacillus acidophilus appears to have some basis.