Probiotics exert specific cell-mediated and humoral immune responses via the immunological gut barrier and play a critical role in modulating T-helper (Th) cell responses and restoring Th1/Th2 balance,¹ which in turn prevents the development of allergies.²

Research has identified a range of specialised probiotic strains to have a preventative effect on atopic dermatitis (AD) in infants and very young children,³ and to provide symptomatic relief in older children with the condition.⁴

 

Clinical Application of Research

Essential take-away messages of the research are detailed below to assist practitioners in their clinical use of specific probiotic strains in AD patients:

• Clinical Use: Atopic Dermatitis
• Clinically Effective Dose for Prevention (a): 3 billion (3 x 109) CFU daily of Bifidobacterium (B.) bifidum W23, B. lactis W51, B. lactis W52, and Lactococcus (Lc.) Lactis W58 in 10 ml of water administered to mothers with a positive family history of allergic disease during the last 6 weeks of pregnancy (prenatally), as well as during breastfeeding and/or in infant formula during the infant’s first year of life (postnatally).³
• Clinically Effective Dose for Treatment (b): 1 billion CFU twice daily (2 x 109) of a formulation containing B. bifidum (W23), L. acidophilus (W55), L. casei (W56), and L. salivarius (W57) in children aged 1-13 years.⁴
• Duration & Expected Results (Prevention) (a): Prenatally during the last 6 weeks of pregnancy and postnatally for the first year of life.³
• Duration & Expected Results (Treatment) (b): Eight weeks of supplementation to reduce atopic dermatitis patients' SCORAD index, serum IL-5, IL-6, IFN-γ, and total serum IgE levels.⁴
• Drug Interactions & Safety Concerns of Probiotics: Probiotics are generally regarded as safe in most populations. However, they should be used with caution or avoided in immune-compromised patients (i.e. in those with AIDS, lymphoma, or those receiving long-term corticosteroid therapy, anti-rejection medication, injectable immunosuppressive drugs, chemotherapy or radiation) as well as the critically ill.^5-8 Avoid in those with cow’s milk allergy.

 

Research Update- Study Details

The trials featured in this research update were both double-blind, randomized, and placebo-controlled that involved specific probiotics with the strain designations W23, W51, W52, W55, W56, W57, W58.

For preventive purposes, these probiotics must be given in the last trimester of pregnancy to mothers whose offspring are at high risk, as well as during breastfeeding, and then in their offspring during the first year of life.³ This particular administration regime is supported by the World Allergy Organisation (WAO) who intends to educate both parents and health care professionals on the most effective use of probiotics for allergy prevention.⁹

Preventive effects on the occurrence of AD were demonstrated using a probiotic mixture consisting of B. bifidum W23, B. lactis W51, B. lactis 52, and Lc. Lactis W58. These specific strains were administered prenatally and postnatally in either 10 ml of water, breast milk or infants’ formula. Out of 156 pregnant women included in the study, 102 completed the three months of follow up, with 98 followed up at 12 and 24 months. Based on weekly diaries, the incidence of parents-reported eczema was slightly higher than that of practitioners. Parents reported an incidence of 15/52 (29%) in the placebo group and 6/50 (12%) in the treatment group, while physician-reported incidence was 11/52 (21%) in the placebo group and 3/50 (6%) in the treatment group. These considerable preventive effects appeared to be established within the first 3 months of life and were sustained during the first 2 years of life.³

Treatment effects of the probiotic strains B. bifidum (W23), L. acidophilus (W55), L. casei (W56), and L. salivarius (W57) were demonstrated in 40 children (23 males and 17 females) with AD aged one 1 to 13 years. Over an 8 week period, supplementation with these strains in soluble powder form effectively reduced the extent and severity of eczema (SCORAD index), as well as serum inflammatory markers, including the cytokines interleukin (IL)-5, IL-6, interferon (IFN)-γ, and total serum IgE levels compared to the placebo group.⁴

The findings of the two studies are of great clinical importance due to a considerable prevalence of AD, especially in the young. According to the Australasian Society of Clinical Immunology and Allergy (ASCIA), AD occurs most commonly in infants, with around one in five effected. It causes unpleasant rashes and dryness on the face, ears and neck, in elbow creases, behind the knees, and across the ankles. In addition, AD often coexists with other allergies such as allergic rhinitis (AR, hay fever), asthma, food allergy or dust mite allergy,10 making prevention and treatment all the more important.

Background- Mechanisms of Action of Probiotics Mitigating Allergic Response

Probiotics exert specific cell-mediated and humoral immune responses via the immunological gut barrier where they stimulate gut associated lymphoid tissue or ‘GALT’ and induce the maturation of antigen-presenting cells or ‘dendritic cells’ (DC). DCs play a critical role in modulating-helper (Th) cell responses and the restoration of Th1/Th2 balance,¹ which in turn prevents the development of allergy.² Probiotics also work via non- or aspecific mechanisms of action.^1,11-15 In summary, specific and non-specific mechanisms of action by which probiotics help to avert allergic responses include:

• Regulating cell-mediated and humoral immune response
  • Inducing CD and Treg cells
  • Stimulating Th1 / suppressing Th2
  • Increasing IgA and decreasing IgE
• Restoring gut wall integrity / intestinal permeability
  • Increasing TJs and decreasing mucins
• Competitively inhibiting adhesion of harmful bacteria
• Modifying the local microenvironment
• Reducing intestinal inflammation

References

• Güvenç IA, Muluk NB, Mutlu FŞ, Eşki E, Altıntoprak N, Oktemer T, Cingi C. Do probiotics have a role in the treatment of allergic rhinitis? A comprehensive systematic review and meta-analysis. Am J Rhinol Allergy. 2016 Sep 1;30(5):157-175.
• Toh ZQ, Anzela A, Tang ML, Licciardi PV. Probiotic therapy as a novel approach for allergic disease. Front Pharmacol. 2012 Sep 21;3:171.
• Niers L, Martín R, Rijkers G, Sengers F, Timmerman H, van Uden N, et al. The effects of selected probiotic strains on the development of eczema (the PandA study). Allergy. 2009 Sep;64(9):1349-58.
• Yeşilova Y, Çalka Ö, Akdeniz N, Berktaş Effect of probiotics on the treatment of children with atopic dermatitis. Ann Dermatol. 2012;24(2):189-193.
• Guarner F, Khan AG, Garisch J, Eliakim R, Gangl A, Thomson A, et al. World Gastroenterology Organization. World Gastroenterology Organisation Global Guidelines: probiotics and prebiotics October 2011. J Clin Gastroenterol. 2012 Jul;46(6):468-81.
• Doron S, Snydman DR. Risk and safety of probiotics. Clin Infect Dis. 2015 May 15;60 Suppl 2(Suppl 2):S129-34.
• Health Canada. Probiotics. Monograph. 2019. Available at: http://webprod.hc-sc.gc.ca/nhpid-bdipsn/atReq.do?atid=probio&lang=eng
• Braun L. and Cohen M. Herbs and Natural Supplements, 4th Edition, Volume 2, Churchill Livingstone, Sydney, 2015, pp.771-796.
• Fiocchi A, Pawankar R, Cuello-Garcia C, Ahn K, Al-Hammadi S, Agarwal A, et al. World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Probiotics. World Allergy Organ J. 2015 Jan 27;8(1):4.
• Australasian Society of Clinical Immunology and Allergy (ASCIA). Eczema (Atopic Dermatitis) Fast Facts. 2019. Available from: https://www.allergy.org.au/images/pcc/ff/ASCIA_Eczema_Fast_Facts_2019.pdf
• Iacono A, Raso GM, Canani RB, Calignano A, Meli R. Probiotics as an emerging therapeutic strategy to treat NAFLD: focus on molecular and biochemical mechanisms. J Nutr Biochem. 2011 Aug;22(8):699-711.
• Sampson HA, O'Mahony L, Burks AW, Plaut M, Lack G, Akdis CA. Mechanisms of food allergy. J Allergy Clin Immunol. 2018 Jan;141(1):11-19.
• Sanders ME, Merenstein DJ, Reid G, Gibson GR, Rastall RA. Probiotics and prebiotics in intestinal health and disease: from biology to the clinic. Nat Rev Gastroenterol Hepatol. 2019 Oct;16(10):605-616.
• Pascal M, Perez-Gordo M, Caballero T, Escribese MM, Lopez Longo MN, Luengo O, Manso L, Matheu V, Seoane E, Zamorano M, Labrador M, Mayorga C. Microbiome and Allergic Diseases. Front Immunol. 2018 Jul 17;9:1584.
• Ipci K, Altıntoprak N, Muluk NB, Senturk M, Cingi C. The possible mechanisms of the human microbiome in allergic diseases. Eur Arch Otorhinolaryngol. 2017 Feb;274(2):617-626.