Total IgE at 6 months predicts remittance or persistence of atopic dermatitis at 14 months

Short- and Long-Lived Autoantibody-Secreting Cells in Autoimmune Neurological Disorders

As B cells differentiate into antibody-secreting cells (ASCs), short-lived plasmablasts (SLPBs) are produced by a primary extrafollicular response, followed by the generation of memory B cells and long-lived plasma cells (LLPCs) in germinal centers (GCs). Generation of IgG4 antibodies is T helper type 2 (Th2) and IL-4, -13, and -10-driven and can occur parallel to IgE, in response to chronic stimulation by allergens and helminths. Although IgG4 antibodies are non-crosslinking and have limited ability to mobilize complement and cellular cytotoxicity, when self-tolerance is lost, they can disrupt ligand-receptor binding and cause a wide range of autoimmune disorders including neurological autoimmunity. In myasthenia gravis with predominantly IgG4 autoantibodies against muscle-specific kinase (MuSK), it has been observed that one-time CD20⁺ B cell depletion with rituximab commonly leads to long-term remission and a marked reduction in autoantibody titer, pointing to a short-lived nature of autoantibody-secreting cells. This is also observed in other predominantly IgG4 autoantibody-mediated neurological disorders, such as chronic inflammatory demyelinating polyneuropathy and autoimmune encephalitis with autoantibodies against the Ranvier paranode and juxtaparanode, respectively, and extends beyond neurological autoimmunity as well. Although IgG1 autoantibody-mediated neurological disorders can also respond well to rituximab induction therapy in combination with an autoantibody titer drop, remission tends to be less long-lasting and cases where titers are refractory tend to occur more often than in IgG4 autoimmunity. Moreover, presence of GC-like structures in the thymus of myasthenic patients with predominantly IgG1 autoantibodies against the acetylcholine receptor and in ovarian teratomas of autoimmune encephalitis patients with predominantly IgG1 autoantibodies against the N‐methyl‐d‐aspartate receptor (NMDAR) confers increased the ability to generate LLPCs. Here, we review available information on the short-and long-lived nature of ASCs in IgG1 and IgG4 autoantibody-mediated neurological disorders and highlight common mechanisms as well as differences, all of which can inform therapeutic strategies and personalized medical approaches.

Detection of ovomucoid-specific low-affinity IgE in infants and its relationship to eczema

BACKGROUND

Allergen-specific low-affinity IgE was previously detected in cord blood by a highly sensitive densely carboxylated protein (DCP) chip, but not by ImmunoCAP. Here, we investigated the presence of low-affinity IgE during the early life of infants and observed its relationship with eczema.

METHODS

We conducted a birth cohort study, collecting sera at birth and 6 and 14 months of age (n = 110). We monitored the ovomucoid (OM)- and egg white (EW)-specific IgE (sIgE) by ImmunoCAP or DCP chip and analyzed the antigen affinity of sIgE by binding inhibition assays in the presence or absence of a mild chaotropic agent, diethyl amine (DEA). The low- and high-affinity OM-sIgEs and sensitization risk factors were analyzed by a multivariate logistic analysis.

RESULTS

The OM-sIgE measured by DCP chip significantly correlated with that measured by ImmunoCAP, but some samples assessed as OM-sIgE positive by DCP chip were considered OM-sIgE negative by ImmunoCAP. Binding inhibition analysis after DEA treatment was performed for participants judged as OM-sIgE positive by DCP chip at 14 M. The group assessed as negative for OM- and EW-sIgE by ImmunoCAP at 6 and 14 months showed a larger binding inhibition curve shift after DEA treatment than did the group assessed as positive at these times, indicating the presence of low-affinity sIgE antibodies at 14 months. The logistic regression analysis found that persistent eczema from 6 to 14 months is a significant risk factor for developing high-affinity, but not low-affinity, sIgE.

CONCLUSIONS

Human infant peripheral blood contains allergen-specific low-affinity sIgE. Persistent eczema is related to the development of high-affinity, but not low-affinity, IgE.

Persistence of atopic dermatitis (AD): A systematic review and meta-analysis

BACKGROUND

Previous studies found conflicting results about whether childhood atopic dermatitis (AD) persists into adulthood.

OBJECTIVE

We sought to determine persistence rates and clinical factors associated with prolonged AD.

METHODS

A systematic review was performed in MEDLINE, EMBASE, Scopus, GREAT, LILACS, Web of Science, Academic Search Complete, and Cochrane Library. Meta-analysis was performed using Kaplan-Meier plots and random-effects proportional hazards regression.

RESULTS

In total, 45 studies including 110,651 subjects spanning 434,992 patient-years from 15 countries were included. In pooled analysis, 80% of childhood AD did not persist by 8 years and less than 5% persisted by 20 years after diagnosis (mean ± SE: 6.1 ± 0.02 years). Children with AD that persisted already for more than 10 years (8.3 ± 0.08 years) had longer persistence than those with 3 (3.2 ± 0.02 years) or 5 (6.8 ± 0.06 years) years of persistence. Children who developed AD by age 2 years had less persistent disease (P < .0001). Persistence was greater in studies using patient-/caregiver-assessed versus physician-assessed outcomes, female versus male patients (P ≤ .0006), but not in those with sensitivity to allergens (P = .90). Three studies found prolonged persistence with more severe AD.

LIMITATIONS

Some studies did not capture recurrences later in life.

CONCLUSIONS

Most childhood AD remitted by adulthood. However, children with already persistent disease, later onset, and/or more severe disease have increased persistence.

Predictive factors of persistent infantile atopic dermatitis up to 6 years old in Taiwan: a prospective birth cohort study

BACKGROUND

Atopic dermatitis affects 15-30% of children worldwide. Onset of disease usually occurs within the first year of life, over half of which regress by 6 years of age. The aim of this study was to investigate the risk factors related to the persistence of infantile atopic dermatitis.

METHODS

In this birth cohort study, patients were enrolled prenatally and followed until 6 years of age; 246 patients had infantile atopic dermatitis at 6 months of age. Family history, maternal and paternal total and specific Immunoglobulin E (IgE) levels, and cord blood IgE were recorded. Clinical examination, questionnaire survey, and blood samples for total and specific IgE of the children were collected at each follow-up visit.

RESULTS

Of the 246 patients with infantile atopic dermatitis at 6 months of age, 48 patients had persisted atopic dermatitis at 6 years of age (19.5%). Risk factors associated with persistent infantile atopic dermatitis included egg white sensitization (odds ratio: 3.801, P = 0.020), and atopic dermatitis involving two or more areas at 6 months old (odds ratio: 2.921, P = 0.018) after multivariate analysis with logistic regression. Patients with persistent infantile atopic dermatitis had a higher risk of asthma before 6 years old (39.6% vs 24.2%, P = 0.032).

CONCLUSION

Egg white sensitization and the initial involvement of two or more areas at 6 months of age were associated with the persistent infantile atopic dermatitis. Patients with persistent infantile atopic dermatitis are more likely to develop asthma by 6 years of age.

Association between egg and staphylococcal superantigen IgE sensitizations in atopic dermatitis

Patients with moderately severe atopic dermatitis (AD) suffer from significant morbidity including secondary infections and psychosocial disturbances. However, there is currently no laboratory test for identifying these patients to implement early treatments. Because IgE sensitization to foods is frequently an early manifestation in infants with AD, this study aims to examine if food IgE levels may identify AD patients with more severe disease, and whether IgE sensitization to food may predict IgE sensitization to staphylococcal superantigens. Fifty-one young children with AD were included in the study. Eczema severity was measured by objective scoring AD. The levels of food and staphylococcal superantigen-specific IgE were measured by Phadia ImmunoCAP system. Of the five common food allergens (cow's milk, egg white, soybean, wheat, and peanut), only IgE levels to egg white correlated significantly with eczema severity in young children with AD. IgE sensitization to egg white was significantly associated with IgE sensitization to staphylococcal superantigens in older children.