HLA-DRB1*01 allele and low plasma immunoglobulin G1 concentration may predispose to herpes-associated recurrent lymphocytic meningitis

Lower serum AMH concentration is correlated with serum IgG1 decreased in the infertile woman: A real-world retrospective study

OBJECTIVES

In this real-world approach, we examined the serum Anti-Mullerian Hormone (AMH) level and the relationship with serum IgG subclass in the infertile women.

METHODS

A total of 574 female participants were recruited for this study. The serum AMH, IgG subclass(IgG1, IgG2, IgG3, IgG4) and immunoglobulin (Ig) G、IgM、IgA、IgE as well as complement C3, C4 were analyzed. The difference in serum AMH level was assessed according categorized as above or below the median of the ratio of serum IgG subclass(IgG1, IgG2, IgG3, IgG4) to total IgG (RIgG subclass/IgG).

RESULTS

The serum AMH level of the low RIgG1/IgG group is significantly decreased than that high RIgG1/IgG group (p < 0.05). The Spearman correlation analysis showed that the serum AMH level was significantly negatively correlated with age and significantly positively correlated with serum IgG1 levels respectively (p < 0.05). GLMMs multivariate model showed that after adjusting the covariate and possible mixed factors including age, serum immunoglobulin, complement C3 and C4, the serum AMH level was significantly positively correlated with IgG1 level (p < 0.01).

CONCLUSIONS

Decreased serum IgG1 may significantly affect the ovarian reserve function of women. Confirmation of this association and elucidation of its underlying mechanisms are needed to place these results in a clinical perspective.

High-resolution HLA genotyping identifies risk alleles in both class I and II for primary autoimmune neutropenia in early childhood in a Danish cohort

HLA studies in patients with autoimmune neutropenia (AIN) have shown very consistent results for the association with HLA class II alleles at low resolution. This study aimed to examine the association of both HLA class I and class II at high resolution to clarify the contribution of risk alleles to the disease. A total of 107 AIN patients were genotyped for six loci of HLA class I (HLA-A, -B and -C) and class II (HLA-DRB1, -DQB1, and -DPB1) genes by a high-resolution (3-field, 6-digit) analysis and compared with HLA typing of 1000 healthy controls. Compared with the controls, the allele frequencies were significantly higher in AIN patients for A*02:17:01G, C*01:02:01G, DRB1*10:01:01G, DRB1*14:01:01G, DRB1*16:01:01G, DQB1*05:02:01G, and DQB1*05:03:01G but lower significant for C*03:04:01G, DRB1*04:01:01G, DRB1*13:02:01G, DQB1*03:02:01G, and DQB1*06:04:01G. Frequently associated two-locus haplotypes were found to be DRB1*10:01:01G-DQB1*05:01:01G and DRB1*16:01:01G-DQB1*05:02:01G, while the S2 (Q- or D-KRAA) shared epitope (SE) was associated with lower risk. A unique association with HLA alleles was observed between patients with specific anti-HNA-1a antibodies and broad-reacting anti-FcγRIIIb. Anti-HNA-1a antibody-positive patients were associated with C*01:02:01G, DRB1*01:01:01G, DRB1*16:01:01G, DQB1*05:01:01G, DQB1*05:02:01G, DQB1*06:04:01G, and DPB1*10:01:01G; the two-locus haplotypes DRB1*01:01:01G-DQB1*05:01:01G and DRB1*16:01:01G-DQB1*05:02:01G; and the S3P (Q- or R-RRAA) SE. Anti-FcγRIIIb antibody-positive patients were associated with the alleles A*02:17:01G, DRB1*10:01:01G, and DQB1*05:02:01G; the haplotypes DRB1*10:01:01G-DQB1*05:01:01G and DRB1*11:01:02G-DQB1*05:02:01G; and the S3D (DRRAA) SE. The different associations regarding FcγRIIIb antibody specificities could indicate disease heterogeneity.

Mollaret Meningitis Caused by Varicella-Zoster Virus: A Case Report

Mollaret meningitis is a recurrent aseptic meningitis mostly caused by herpes simplex virus type 2. Other causes of the disease rarely exist, and its pathology is not well understood. Herein, we present a 57-year-old man who had been admitted to our hospital eight times with recurrent aseptic meningitis. Although the deoxyribonucleic acid (DNA) of varicella-zoster virus (VZV) was not detected in the cerebrospinal fluid (CSF), his genetic analysis, measurement of anti-VZV immunoglobulin-G (IgG) in the CSF, the VZV IgG index, IgG in the serum, and interleukin-1 beta in the CSF revealed that the Mollaret meningitis had been caused by the VZV. This case demonstrates that Mollaret meningitis can be caused by the VZV when specific factors are associated with decreased immune response. This case is valuable in elucidating the pathophysiology of Mollaret meningitis.

The relevance of complement in pemphigoid diseases: A critical appraisal

Pemphigoid diseases are autoimmune chronic inflammatory skin diseases, which are characterized by blistering of the skin and/or mucous membranes, and circulating and tissue-bound autoantibodies. The well-established pathomechanisms comprise autoantibodies targeting various structural proteins located at the dermal-epidermal junction, leading to complement factor binding and activation. Several effector cells are thus attracted and activated, which in turn inflict characteristic tissue damage and subepidermal blistering. Moreover, the detection of linear complement deposits in the skin is a diagnostic hallmark of all pemphigoid diseases. However, recent studies showed that blistering might also occur independently of complement. This review reassesses the importance of complement in pemphigoid diseases based on current research by contrasting and contextualizing data from in vitro, murine and human studies.

Interplay of Environmental, Individual and Genetic Factors in Rheumatoid Arthritis Provocation

In this review, we explore systemization of knowledge about the triggering effects of non-genetic factors in pathogenic mechanisms that contribute to the development of rheumatoid arthritis (RA). Possible mechanisms involving environmental and individual factors in RA pathogenesis were analyzed, namely, infections, mental stress, sleep deprivation ecology, age, perinatal and gender factors, eating habits, obesity and smoking. The non-genetic factors modulate basic processes in the body with the impact of these factors being non-specific, but these common challenges may be decisive for advancement of the disease in the predisposed body at risk for RA. The provocation of this particular disease is associated with the presence of congenital loci minoris resistentia. The more frequent non-genetic factors form tangles of interdependent relationships and, thereby, several interdependent external factors hit one vulnerable basic process at once, either provoking or reinforcing each other. Understanding the specific mechanisms by which environmental and individual factors impact an individual under RA risk in the preclinical stages can contribute to early disease diagnosis and, if the factor is modifiable, might be useful for the prevention or delay of its development.

Recurrent Herpes Simplex Virus 2 Lymphocytic Meningitis in Patient with IgG Subclass 2 Deficiency

We report a case of a patient with a lifetime history of 8 episodes of recurrent lymphocytic meningitis. Our findings suggest that susceptibility to recurrent lymphocytic meningitis might be caused by low serum IgG subclass 2 immunodeficiency.

HLA Class I and II alleles, heterozygosity and HLA-KIR interactions are associated with rates of genital HSV shedding and lesions

Variation at HLA and KIR loci is associated with the severity of viral infections. To assess associations of genital HSV-2 infection with human HLA and KIR genetic loci, we measured the frequencies of genital HSV DNA detection and of genital lesions in HSV-2 seropositive persons. We followed 267 HSV-2 seropositive persons who collected daily genital swabs and recorded lesions for ≥30 days. All persons were laboratory- documented as HIV-seronegative, and all were Caucasian by self-report. HSV detection rate and lesion frequency were compared by genotype using Poisson regression. Overall, HSV was detected on 19.1% of days and lesions on 11.6% of days. The presence of HLA-A*01 was directly associated with HSV detection frequency while the presence of HLA-C*12 was inversely associated with HSV detection frequency. The presence of HLA-A*01 was directly associated with lesion rate, while HLA-A*26, -C*01 and -DQB1*0106 were associated with decreased lesions. We observed an interaction between the absence of both 2DS4del and HLA-Bw4 and higher lesion rate. Heterozygosity of HLA was also associated with reduced lesion frequency. Immune control of genital HSV infection relies on multiple interacting immunogenetic elements, including epistatic interactions between HLA and KIR.

How Rheumatoid Arthritis Can Result from Provocation of the Immune System by Microorganisms and Viruses

The pathogenesis of rheumatoid arthritis (RA), similar to development of a majority of inflammatory and autoimmune disorders, is largely due to an inappropriate or inadequate immune response to environmental challenges. Among these challenges, infectious agents are the undisputed leaders. Since the 1870s, an impressive list of microorganisms suspected of provoking RA has formed, and the list is still growing. Although a definite causative link between a specific infectious agent and the disease has not been established, several arguments support such a possibility. First, in the absence of a defined pathogen, the spectrum of triggering agents may include polymicrobial communities or the cumulative effect of several bacterial/viral factors. Second, the range of infectious episodes (i.e., clinical manifestations caused by pathogens) may vary in the process of RA development from preclinical to late-stage disease. Third, infectious agents might not trigger RA in all cases, but trigger it in a certain subset of the cases, or the disease onset may arise from an unfortunate combination of infections along with, for example, psychological stress and/or chronic joint tissue microtrauma. Fourth, genetic differences may have a role in the disease onset. In this review, two aspects of the problem of “microorganisms and RA” are debated. First, is there an acquired immune deficiency and, in turn, susceptibility to infections in RA patients due to the too frequent and too lengthy infections, which at last break the tolerance of self antigens? Or, second, is there a congenital deficiency in tolerance and inflammation control, which may occur even with ordinary infection frequency and duration?

Complement system in dermatological diseases - fire under the skin

The complement system plays a key role in several dermatological diseases. Overactivation, deficiency, or abnormality of the control proteins are often related to a skin disease. Autoimmune mechanisms with autoantibodies and a cytotoxic effect of the complement membrane attack complex on epidermal or vascular cells can cause direct tissue damage and inflammation, e.g., in systemic lupus erythematosus (SLE), phospholipid antibody syndrome, and bullous skin diseases like pemphigoid. By evading complement attack, some microbes like Borrelia spirochetes and staphylococci can persist in the skin and cause prolonged symptoms. In this review, we present the most important skin diseases connected to abnormalities in the function of the complement system. Drugs having an effect on the complement system are also briefly described. On one hand, drugs with free hydroxyl on amino groups (e.g., hydralazine, procainamide) could interact with C4A, C4B, or C3 and cause an SLE-like disease. On the other hand, progress in studies on complement has led to novel anti-complement drugs (recombinant C1-inhibitor and anti-C5 antibody, eculizumab) that could alleviate symptoms in diseases associated with excessive complement activation. The main theme of the manuscript is to show how relevant the complement system is as an immune effector system in contributing to tissue injury and inflammation in a broad range of skin disorders.

Diversity of extended HLA-DRB1 haplotypes in the Finnish population

The Major Histocompatibility Complex (MHC, 6p21) codes for traditional HLA and other host response related genes. The polymorphic HLA-DRB1 gene in MHC Class II has been associated with several complex diseases. In this study we focus on MHC haplotype structures in the Finnish population. We explore the variability of extended HLA-DRB1 haplotypes in relation to the other traditional HLA genes and a selected group of MHC class III genes. A total of 150 healthy Finnish individuals were included in the study. Subjects were genotyped for HLA alleles (HLA-A, -B, -DRB1, -DQB1, and -DPB1). The polymorphism of TNF, LTA, C4, BTNL2 and HLA-DRA genes was studied with 74 SNPs (single nucleotide polymorphism). The C4A and C4B gene copy numbers and a 2-bp silencing insertion at exon 29 in C4A gene were analysed with quantitative genomic realtime-PCR. The allele frequencies for each locus were calculated and haplotypes were constructed using both the traditional HLA alleles and SNP blocks. The most frequent Finnish A∼B∼DR -haplotype, uncommon in elsewhere in Europe, was A*03∼B*35∼DRB1*01∶01. The second most common haplotype was a common European ancestral haplotype AH 8.1 (A*01∼B*08∼DRB1*03∶01). Extended haplotypes containing HLA-B, TNF block, C4 and HLA-DPB1 strongly increased the number of HLA-DRB1 haplotypes showing variability in the extended HLA-DRB1 haplotype structures. On the contrary, BTNL2 block and HLA-DQB1 were more conserved showing linkage with the HLA-DRB1 alleles. We show that the use of HLA-DRB1 haplotypes rather than single HLA-DRB1 alleles is advantageous when studying the polymorphisms and LD patters of the MHC region. For disease association studies the HLA-DRB1 haplotypes with various MHC markers allows us to cluster haplotypes with functionally important gene variants such as C4 deficiency and cytokines TNF and LTA, and provides hypotheses for further assessment. Our study corroborates the importance of studying population-specific MHC haplotypes.

HLA-DRB1 allele frequencies and C4 copy number variation in Finnish sarcoidosis patients and associations with disease prognosis

Sarcoidosis is a multiorgan immune-mediated disease of unknown etiology with varying clinical pictures. We studied 3 genes in the major histocompatibility complex region (HLA-DRB1 and complement C4A and C4B) in patients with resolved disease after a 2-year follow-up (n = 90) and in patients whose disease was still active at that time point (n = 98) and compared them with controls (n = 150). Our primary aim was to detect genetic differences between the patient groups. We observed that the susceptibility allele for sarcoidosis was HLA-DRB1*15:01 (p = 0.011; odds ratio [OR] = 1.67) and the protective allele was HLA-DRB1*01:01 (p = 0.001; OR = 0.43). HLA-DRB1*03:01 was associated with resolving disease when compared with the persistent group (p = 0.011; OR = 2.22). The probability of having resolving disease was even greater if the patient had HLA-DRB1*03:01 and did not have extrapulmonary lesions (p = 0.001; OR = 3.39). By evaluating amino acid variants of the HLA-DRB1 gene, we determined that specific amino acids in pockets 4, 7, and 9 were associated with the prognosis of sarcoidosis. Our results support the importance of HLA-DRB1 as a predisposing gene for sarcoidosis. Particularly, HLA-DRB1*03:01 and polymorphisms of DRB1 pocket residues were associated with a favorable prognosis. Thus, accurate categorization of disease phenotype and HLA-DRB1 sequencing offer a basis for disease course estimation of sarcoidosis.