Cellular abnormalities in patients with elevated serum IgE levels

Causal relationship between the blood immune cells and intervertebral disc degeneration: univariable, bidirectional and multivariable Mendelian randomization

Background

Intervertebral disc degeneration (IVDD) is a prominent contributor to chronic low back pain, impacting millions of individuals annually. Current research on disc degeneration is placing a growing emphasis on the role of the immune system in this process. Nevertheless, the precise relationship between immunity and disc degeneration remains to be fully elucidated.

Method

We obtained GWAS data for immune cells from the latest summary-level GWAS, including 6,620 individuals from Sardinian and 746,667 individuals from five global populations. Summary results for IVDD were sourced from the FinnGen consortium, comprising 20,001 cases and 164,682 controls. We conducted a comprehensive univariable Mendelian randomization (MR) analysis to explore the potential causal relationship between immune cells and IVDD. Primary estimation was carried out using Inverse-Variance Weighting (IVW). To ensure robustness, we employed additional MR methods such as MR-Egger, Weighted Median, Weighted Mode, and Simple Mode. Various tests were employed to assess pleiotropy and heterogeneity, including the Cochran Q test, leave-one-out test, MR-Egger intercept analysis and MR-PRESSO test. To account for potential confounding factors among the immune cells, we conducted a multivariable MR analysis. Finally, we investigated the possibility of a reverse association between immune cells and IVDD through bidirectional MR.

Result

In total, our study identified 15 immune cells significantly associated with IVDD through univariable MR. Among these, 9 immune cell types were indicated as potential contributors to IVDD, while 6 were found to have protective effects. Importantly, we observed no evidence of heterogeneity or pleiotropy, signifying the robustness of our results. To mitigate confounding among immune cells, we utilized multivariable MR, leading to the discovery that only 9 immune cell types exerted independent effects on IVDD. These encompassed 7 as risk factors and 2 as protective factors. Additionally, our analysis revealed a bidirectional causal relationship between CD39+ CD4+ T cell %CD4+ T cell and IVDD.

Conclusion

Our findings suggest a connection between immune cells and the risk of IVDD, shedding light on potential therapeutic avenues for modulating immune cell function in individuals with IVDD. However, the specific underlying mechanisms warrant further investigation in future experiments.

Correlation between radiculalgia and counts of T lymphocyte subsets in the peripheral blood of patients with lumbar disc herniation

OBJECTIVE

To determine the correlation between the degree of radiculalgia and counts of T lymphocyte subsets in the peripheral blood of patients with lumbar disc herniation.

METHODS

Forty-nine patients with lumbar disc herniation (group A) were divided into three subgroups according to Visual Analogue Scale (VAS) pain scores (group A(1): n= 12, VAS 0-4.0; A(2): n= 24, VAS 4.1-7.0; A(3): n= 13, VAS 7.1-10.0. Twenty health blood donors who volunteered to be involved in the study comprised the control group (group B). Peripheral blood counts of various T lymphocyte subsets were measured in each group.

RESULTS

(i) The counts of CD4+ T and CD4+/CD8+ lymphocytes were higher in group A than in group B, and the difference between the two groups was statistically significant (P < 0.05). There were also statistically significant differences between group A and group B in the counts of CD3+ and CD8+ T lymphocytes (P < 0.05); (ii) There was no correlation between the VAS scores and the counts of CD3+ T lymphocytes (r= 0.194, P > 0.05). A strong significant correlation was observed between the VAS scores and counts of CD4+ T lymphocytes (r= 0.542, P < 0.05), CD4+/CD8+ (r= 0.468, P < 0.05), which increased with increasing VAS scores in the three subgroups of group A (P < 0.05). However there was a significant negative linear correlation between CD8+ T lymphocyte counts and pain scores (r=-0.462, P < 0.05).

CONCLUSION

Our results suggest that changes in T lymphocyte subsets in peripheral blood take place after prolapse of lumbar intervertebral discs. The current results may provide support for involvement of immunologic mechanisms in low back pain secondary to herniation of the lumbar disc. T lymphocytes may play an important role in the development of symptoms in patients with lumbar intervertebral disc herniation.

Fc epsilon receptor II/CD23+ lymphocytes in atopic dermatitis. III. Aberrant control in the in vitro expression of Fc epsilon RII/CD23 on peripheral blood T cells in atopic dermatitis

In vitro Fc epsilon RII expression was examined in patients with atopic dermatitis, those with non-atopic eczematous dermatitis and normal individuals following stimulation of peripheral blood cells with recombinant IL-4 (rIL-4), phytohaemagglutinin (PHA), or PHA plus rIL-2. At various days cells were stained with MoAbs to human lymphocyte Fc epsilon RII and to lymphoid cell-surface antigens and analysed by flow cytometry. rIL-4, but not rIL-2, specifically induced Fc epsilon RII on T cells as well as B cells in atopic dermatitis, eczematous dermatitis and normal individual groups. Both atopics and non-atopics generated comparable proportions of Fc epsilon RII+ T cells (T epsilon cells), whereas the frequency of B cells bearing Fc epsilon RII(B epsilon cells) was significantly higher in patients with extensive atopic dermatitis than in those with mild atopic dermatitis and other subjects. Comparable levels of T epsilon cells were detected in both atopic and non-atopic donors following stimulation of peripheral blood cells with PHA or pre-activation of the cells with PHA plus subsequent incubation with rIL-2. Whereas both CD8+ and CD4+ subsets were present in T epsilon cell populations induced specifically by rIL-4, PHA and PHA plus rIL-2, patients with atopic dermatitis had a greater tendency for Fc epsilon RII expression on CD8+ T cells compared with patients with eczematous dermatitis and normal individuals. Recombinant interferon-gamma (rIFN-gamma), but not rIFN-alpha or prostaglandin E2 (PGE2), suppressed the generation of T epsilon cells by rIL-4 in atopics and non-atopics to the same degree. These results suggest the aberrant control of Fc epsilon RII expression on T cells, especially those bearing CD8, in atopic dermatitis.

Fc epsilon receptor II/CD23 positive lymphocytes in atopic dermatitis: II. Infiltration of Fc epsilon R II(+) T cells in the skin lesion

Cells expressing Fc receptors for IgE (Fc epsilon R II) were identified in skin from patients with atopic dermatitis (AD), eczematous dermatitis (ED), and in skin from normal nonatopic subjects, with the use of monoclonal antibodies to human lymphocyte Fc epsilon R II, H107, and to lymphoid cell-surface antigens by double immunofluorescence staining. Two to four percent of infiltrating mononuclear cells expressed Fc epsilon R II, and more than half of these cells were T epsilon cells in both acute and chronic AD lesions. Fc epsilon R II(+) T cells (T epsilon cells) bearing CD8 infiltrated preferentially acute lesions, whereas chronic lesions contained either CD8(+) or CD4(+) T epsilon cells, or both. Fc epsilon R II(+) cells rarely were present in ED lesions. There was no significant correlation between % Fc epsilon R II(+) peripheral blood mononuclear cells and the proportion of lesional Fc epsilon R II(+) cells, extent of skin lesions, or serum IgE levels, implying the selective accumulation of Fc epsilon R II(+) cells in the inflammatory infiltrate of AD. These observations suggest that the increased generation of Fc epsilon R II(+) cells in skin lesions, including CD8 (+) T epsilon cells, is involved in the pathogenesis of AD.

Contrasting disease patterns in psoriasis and atopic dermatitis

In this report we investigate the simultaneous occurrence of psoriasis and atopic dermatitis (AD) as well as the association with infectious skin diseases. Among 29,159 patients hospitalized between 1953 and 1983, 8.5% (2,467 patients) were treated for psoriasis, while 1.6% (470 patients) were hospitalized for AD treatment. On the basis of incidence rates for both diseases, 36 patients (0.14%) with both psoriasis and AD were expected to be seen. However, the two conditions were simultaneously present in 2 patients only. Approximately 30% of the AD patients were suffering from either bacterial or viral infection, while this complication occurred in 6.7% of psoriatics. In addition, among 48 patients hospitalized for eczema herpeticatum 39 were atopics and none was psoriatic. The data demonstrate that the occurrence of psoriasis and AD in one and the same patient is quite rare and this may be related to conflicting immune defense patterns. Thus, increased sensitization against foreign protein together with high susceptibility to cutaneous infection present in AD is in contrast to high phagocyte responsiveness in psoriasis, where concurrent infections are rare.