Margit Hørup Larsen

Human leukocyte antigen-G polymorphism in relation to expression, function, and disease

Human leukocyte antigen-G (HLA-G) is a nonclassical class Ib molecule belonging to the major histocompatibility complex. HLA-G appears to play a role in the suppression of immune responses and contribute to long-term immune escape or tolerance. The focus of this review is polymorphism in the HLA-G gene and protein and its possible importance in expression, function, and disease associations.

Soluble human leukocyte antigen-G isoforms in maternal plasma in early and late pregnancy.

Problem Human Leukocyte Antigen (HLA)‐G is a class Ib gene located in the human major histocompatibility complex (MHC). Several lines of investigation indicate that the HLA‐G molecule is involved in the maternal acceptance of the semi‐allogenic fetus during pregnancy and in the development of tolerance. Expression of soluble HLA‐G (sHLA‐G) is positively correlated with successful in vitro fertilization (IVF) treatments, and aberrant expression of HLA‐G in certain complications of pregnancy, such as pre‐eclampsia and spontaneous abortion, has been reported. The main purpose of this study was to investigate the levels of different soluble HLA‐G isoforms in maternal plasma in early and late pregnancy.

ORIGINAL ARTICLE: Soluble Human Leukocyte Antigen-G Isoforms in Maternal Plasma in Early and Late Pregnancy

Problem Human Leukocyte Antigen (HLA)‐G is a class Ib gene located in the human major histocompatibility complex (MHC). Several lines of investigation indicate that the HLA‐G molecule is involved in the maternal acceptance of the semi‐allogenic fetus during pregnancy and in the development of tolerance. Expression of soluble HLA‐G (sHLA‐G) is positively correlated with successful in vitro fertilization (IVF) treatments, and aberrant expression of HLA‐G in certain complications of pregnancy, such as pre‐eclampsia and spontaneous abortion, has been reported. The main purpose of this study was to investigate the levels of different soluble HLA‐G isoforms in maternal plasma in early and late pregnancy.

Human leukocyte antigen-G in the male reproductive system and in seminal plasma

One of the non-classical human leukocyte antigen (HLA) class Ib proteins, HLA-G, is believed to exert important immunoregulatory functions, especially during pregnancy. The presence of HLA protein in paternal seminal fluid has been suggested to have an influence on the risk of developing pre-eclampsia. We have investigated whether HLA-G protein is present in human seminal plasma and in different tissue samples of the male reproductive system. Western blot technique and a soluble HLA-G (sHLA-G) assay were used to detect sHLA-G in human seminal plasma samples. Immunohistochemical staining was performed on paraffin-embedded tissue samples. We detected sHLA-G protein in seminal plasma, and HLA-G expression in normal testis and in epididymal tissue of the male reproductive system but not in the seminal vesicle. Furthermore, the results indicated a weak expression of HLA-G in hyperplastic prostatic tissue. In summary, several of the findings reported in this study suggest an immunoregulatory role of HLA-G in the male reproductive system and in seminal plasma.

HLA-G 3′ Untranslated Region 14–Base Pair Deletion: Association With Poor Survival in an HIV-1–Infected Zimbabwean Population

We aimed to evaluate whether the HLA-G 14-base pair (bp) polymorphism (rs16375) has an impact on human immunodeficiency virus HIV progression and survival in an antiretroviral therapy-naive Zimbabwean cohort (n = 312). Rs16375 was genotyped using a competitive allele-specific polymerase chain reaction system; CD4 cell counts and HIV RNA were measured with flow cytometry and commercially available polymerase chain reaction; survival was followed up for 4.3 years. The homozygous HLA-G -14-bp genotype is associated with higher viral load (P = .004), lower CD4 cell count (P = .01), and increased mortality (hazard ratio, 1.9; 95% confidence interval, 1.033-3.522; P = .04) compared with HLA-G +14-bp carriers.

CCL3L gene copy number and survival in an HIV-1 infected Zimbabwean population

The C-C motif chemokine ligand 3-like (CCL3L) protein is a potent chemoattractant which by binding to C-C chemokine receptor type 5 (CCR5) inhibits human immunodeficiency virus (HIV) entry. Copy number variation (CNV) of the CCL3L has been shown to be associated with HIV susceptibility and progression to AIDS, but these results have been inconsistent. We examined a Zimbabwean study population for an association of CCL3L CNV with HIV status, progression (CD4 T-cells and viral load), and survival. Another aim was to investigate the possible effects of CCL3L CNV on CCL3 protein concentration. A treatment-naïve cohort, which included 153 HIV infected and 159 HIV uninfected individuals, was followed for up to 4.3 years. The CNV of the CCL3L was determined by duplex real-time polymerase chain reaction. We found no association between four CCL3L CNV strata and HIV status (P=0.7), CD4 T-cell count (P=0.9), viral load (P=0.9), or CCL3 protein levels (P=1.0). Survival among the HIV infected individuals did not differ according to CCL3L copy number. In this cohort, CCL3L CNV did not affect HIV status, pathogenesis, or survival.

Genome-Wide Association Study of Genetic Variants in LPS-Stimulated IL-6, IL-8, IL-10, IL-1ra and TNF-α Cytokine Response in a Danish Cohort

Background Cytokine response plays a vital role in various human lipopolysaccharide (LPS) infectious and inflammatory diseases. This study aimed to find genetic variants that might affect the levels of LPS-induced interleukin (IL)-6, IL-8, IL-10, IL-1ra and tumor necrosis factor (TNF)-α cytokine production. Methods We performed an initial genome-wide association study using Affymetrix Human Mapping 500 K GeneChip® to screen 130 healthy individuals of Danish descent. The levels of IL-6, IL-8, IL-10, IL-1ra and TNF-α in 24-hour LPS-stimulated whole blood samples were compared within different genotypes. The 152 most significant SNPs were replicated using Illumina Golden Gate® GeneChip in an independent cohort of 186 Danish individuals. Next, 9 of the most statistical significant SNPs were replicated using PCR-based genotyping in an independent cohort of 400 Danish individuals. All results were analyzed in a combined study among the 716 Danish individuals. Results Only one marker of the 500 K Gene Chip in the discovery study showed a significant association with LPS-induced IL-1ra cytokine levels after Bonferroni correction (P<10−7). However, this SNP was not associated with the IL-1ra cytokine levels in the replication dataset. No SNPs reached genome-wide significance for the five cytokine levels in the combined analysis of all three stages. Conclusions The associations between the genetic variants and the LPS-induced IL-6, IL-8, IL-10, IL-1ra and TNF-α cytokine levels were not significant in the meta-analysis. This present study does not support a strong genetic effect of LPS-stimulated cytokine production; however, the potential for type II errors should be considered.

Human Leukocyte Antigen-G and Regulatory T Cells during Specific Immunotherapy for Pollen Allergy

Background: T_H2-biased immune responses are important in allergy pathogenesis. Mechanisms of allergen-specific immunotherapy (SIT) might include the induction of regulatory T cells (Tregs) and immunoglobulin (Ig) G₄ blocking antibodies, a reduction in the number of effector cells, and skewing of the cytokine profile towards a T_H1-polarized immune response. We investigated the effects of SIT on T cells, on immunomodulation of human leukocyte antigen (HLA)-G, which has been associated with allergy, on regulatory cytokine expression, and on serum allergen-specific antibody subclasses (IgE and IgG₄). Methods: Eleven birch and/or grass pollen-allergic patients and 10 healthy nonatopic controls were studied before and during SIT. Tregs, chemokine receptors, soluble HLA-G (sHLA-G), Ig-like transcript (ILT) 2, specific IgE, and IgG₄ were studied. Peripheral blood mononuclear cells (PBMCs) were stimulated with pollen extract in vitro and immune factors were evaluated. Results: During SIT, the main changes in the peripheral blood were an increase in CXCR3⁺CD4⁺CD25⁺CD127^low/- Tregs and a decrease in CCR4⁺CD4⁺CD25⁺CD127^low/- Tregs, an increase in allergen-specific IgG₄, and a decrease in sHLA-G during the first half of the treatment period. In the PBMC in vitro experiments, the following changes were observed upon allergen-stimulation: an increase in CD4⁺CD25⁺CD127^low/- Tregs and ILT2⁺CD4⁺CD25⁺CD127^low/- Tregs, an increase in IL-10 and IL-2 levels, and an increase in sHLA-G that was most pronounced at the start of SIT. Conclusions: The changes in CXCR3⁺CD4⁺CD25⁺CD127^low/- Treg, IgG₄, and sHLA-G levels in the peripheral blood and in ILT2⁺ Treg, IL-10, IL-2, and sHLA-G levels upon in vitro allergen stimulation suggest an upregulation in immunomodulatory factors and, to some degree, a shift towards T_H1 during SIT.

Shift work at young age is associated with increased risk of multiple sclerosis in a Danish population

BACKGROUND Epidemiological studies suggest an important role for environmental factors in developing multiple sclerosis (MS). Furthermore several studies have indicated that the effect of environmental factors may be especially pronounced in adolescents. Recently only one study investigated and found that shift work at young age is associated with an increased risk of developing MS. In this study we focused on the effect of shift work in the vulnerable period between 15-19 years. OBJECTIVE The aim of this study was to investigate the association between shift work at young age and the risk of developing MS. METHODS We performed a large case-control study including 1723 patients diagnosed with MS and 4067 controls. MS patients were recruited from the Danish Multiple Sclerosis Biobank and controls from The Danish Blood Donor Study. Information on working patterns and lifestyle factors was obtained using a comprehensive lifestyle-environmental factor questionnaire with participants enrolled between 2009 and 2014. Logistic regression models were used to investigate the association between shift work at age 15-19 years and the subsequent risk of MS and were controlled for effects due to established MS risk factors. RESULTS We found a statistically significant association when total numbers of night shifts were compared with non-shift workers. For every additional 100 night shifts the odds ratio (OR) for MS was 1.20 (95% confidence interval (CI), 1.08-1.34, p=0.001). Increasing intensity of shift work also increased MS risk. For every additional night per month the OR was 1.04 (95% CI, 1.01-1.06, p=0.002). Duration of shift work in years was not associated with risk of MS. CONCLUSION This study supports a statistically significant association between shift work at age 15-19 years and MS risk.

ORIGINAL ARTICLE: Soluble Human Leukocyte Antigen-G Isoforms in Maternal Plasma in Early and Late Pregnancy: MATERNAL SOLUBLE HLA-G ISOFORMS IN A PREGNANCY COHORT

Problem Human Leukocyte Antigen (HLA)‐G is a class Ib gene located in the human major histocompatibility complex (MHC). Several lines of investigation indicate that the HLA‐G molecule is involved in the maternal acceptance of the semi‐allogenic fetus during pregnancy and in the development of tolerance. Expression of soluble HLA‐G (sHLA‐G) is positively correlated with successful in vitro fertilization (IVF) treatments, and aberrant expression of HLA‐G in certain complications of pregnancy, such as pre‐eclampsia and spontaneous abortion, has been reported. The main purpose of this study was to investigate the levels of different soluble HLA‐G isoforms in maternal plasma in early and late pregnancy.