Comparative analysis of HLA class I antigens in pulmonary sarcoidosis and tuberculosis in the same ethnic group

Mycobacterial Heat Shock Proteins in Sarcoidosis and Tuberculosis

Pathological similarities between sarcoidosis (SA) and tuberculosis (TB) suggest the role of mycobacterial antigens in the etiopathogenesis of SA. The Dubaniewicz group revealed that not whole mycobacteria, but Mtb-HSP70, Mtb-HSP 65, and Mtb-HSP16 were detected in the lymph nodes, sera, and precipitated immune complexes in patients with SA and TB. In SA, the Mtb-HSP16 concentration was higher than that of Mtb-HSP70 and that of Mtb-HSP65, whereas in TB, the Mtb-HSP16 level was increased vs. Mtb-HSP70. A high Mtb-HSP16 level, induced by low dose-dependent nitrate/nitrite (NOx), may develop a mycobacterial or propionibacterial genetic dormancy program in SA. In contrast to TB, increased peroxynitrite concentration in supernatants of peripheral blood mononuclear cell cultures treated with Mtb-HSP may explain the low level of NOx detected in SA. In contrast to TB, monocytes in SA were resistant to Mtb-HSP-induced apoptosis, and CD4+T cell apoptosis was increased. Mtb-HSP-induced apoptosis of CD8+T cells was reduced in all tested groups. In Mtb-HSP-stimulated T cells, lower CD8+γδ+IL-4+T cell frequency with increased TNF-α,IL-6,IL-10 and decreased INF-γ,IL-2,IL-4 production were present in SA, as opposed to an increased presence of CD4+γδ+TCR cells with increased TNF-α,IL-6 levels in TB, vs. controls. Mtb-HSP modulating the level of co-stimulatory molecules, regulatory cells, apoptosis, clonal deletion, epitope spread, polyclonal activation and molecular mimicry between human and microbial HSPs may also participate in the induction of autoimmunity, considered in SA. In conclusion, in different genetically predisposed hosts, the same antigens, e.g., Mtb-HSP, may induce the development of TB or SA, including an autoimmune response in sarcoidosis.

HLA-B*13, B*35 and B*39 Alleles Are Closely Associated With the Lack of Response to ART in HIV Infection: A Cohort Study in a Population of Northern Brazil

Introduction

Immune reconstitution failure after HIV treatment is a multifactorial phenomenon that may also be associated with a single polymorphism of human leukocyte antigen (HLA); however, few reports include patients from the Brazilian Amazon. Our objective was to evaluate the association of the immunogenic profile of the “classical” HLA-I and HLA-II loci with treatment nonresponse in a regional cohort monitored over 24 months since HIV diagnosis.

Materials and Methods

Treatment-free participants from reference centers in the state of Pará, Brazil, were enrolled. Infection screening was performed using enzyme immunoassays (Murex AG/AB Combination DiaSorin, UK) and confirmed by immunoblots (Bio-Manguinhos, FIOCRUZ). Plasma viral load was quantified by real-time PCR (ABBOTT, Chicago, Illinois, USA). CD4⁺/CD8⁺ T lymphocyte quantification was performed by immunophenotyping and flow cytometry (BD Biosciences, San Jose, CA, USA). Infection was monitored via test and logistics platforms (SISCEL and SICLOM). Therapeutic response failure was inferred based on CD4⁺ T lymphocyte quantification after 1 year of therapy. Loci A, B and DRB1 were genotyped using PCR-SSO (One Lambda Inc., Canoga Park, CA, USA). Statistical tests were applied using GENEPOP, GraphPad Prism 8.4.3 and BioEstat 5.3.

Results

Of the 270 patients monitored, 134 responded to treatment (CD4⁺ ≥ 500 cells/µL), and 136 did not respond to treatment (CD4⁺ < 500 cells/µL). The allele frequencies of the loci were similar to heterogeneous populations. The allelic profile of locus B was statistically associated with treatment nonresponse, and the B*13, B*35 and B*39 alleles had the greatest probabilistic influence. The B*13 allele had the highest risk of treatment nonresponse, and carriers of the allele had a detectable viral load and a CD4+ T lymphocyte count less than 400 cells/µL with up to 2 years of therapy. The B*13 allele was associated with a switch in treatment regimens, preferably to efavirenz (EFZ)-based regimens, and among those who switched regimens, half had a history of coinfection with tuberculosis.

Conclusions

The allelic variants of the B locus are more associated with non-response to therapy in people living with HIV (PLHIV) from a heterogeneous population in the Brazilian Amazon.

Mycobacterium tuberculosis as a sarcoid factor? A case report of family sarcoidosis

PATIENT

Male, 26 FINAL DIAGNOSIS: Sarcoidosis Symptoms: Disseminated lung parenchymal changes Medication: - Clinical Procedure: - Specialty: Pulmonology.

OBJECTIVE

Rare disease.

BACKGROUND

Sarcoidosis is a granulomatous inflammatory disease that is induced by unknown antigen(s) in a genetically susceptible host. Although the direct link between Mycobacterium tuberculosis (MTB) infection and sarcoidosis can be excluded on the basis of a current knowledge, the non-infectious mechanisms may explain the causative role of mycobacterial antigens. The co-incidence of tuberculosis (TB) and sarcoidosis, and higher incidence of mycobacterial DNA in biological samples of sarcoid patients, have been reported by many authors.

CASE REPORT

We present a case in which MTB infection in 1 family member triggered a sarcoid reaction in the infected subject and 2 other non-infected family members. We discuss different aspects of diagnosis and differentiation, as well as up-to-date hypotheses on the possible mechanisms leading to sarcoid inflammation in patients exposed to MTB.

CONCLUSIONS

This case series documents the possibility of familial spreading of sarcoidosis, and points to MTB as a potential etiological factor.

Microbial and human heat shock proteins as 'danger signals' in sarcoidosis

In the light of the Matzinger's model of immune response, human heat shock proteins (HSPs) as main 'danger signals' (tissue damage-associated molecular patterns-DAMPs) or/and microbial HSPs as pathogen-associated molecular patterns (PAMPs) recognized by pattern recognition receptors (PRR), may induce sarcoid granuloma by both infectious and non-infectious factors in genetically different predisposed host. Regarding infectious causes of sarcoid models, low-virulence strains of, e.g. mycobacteria and propionibacteria recognized through changed PRR and persisting in altered host phagocytes, generate increased release of both human and microbial HSPs with their molecular and functional homology. High chronic spread of human and microbial HSPs altering cytokines, co-stimulatory molecules, and Tregs expression, apoptosis, oxidative stress, induces the autoimmunity, considered in sarcoidosis. Regarding non-infectious causes of sarcoidosis, human HSPs may be released at high levels during chronic low-grade exposure to misfolding amyloid precursor protein in stressed cells, phagocyted metal fumes, pigments with/without aluminum in tattoos, and due to heat shock in firefighters. Therefore, human HSPs as DAMPs and/or microbial HSPs as PAMPs produced as a result of non-infectious and infectious factors may induce different models of sarcoidosis, depending on the genetic background of the host. The number/expression of PRRs/ligands may influence the occurrence of sarcoidosis in particular organs.

Human leukocyte antigen-A, -B, and -DRB1 alleles and sarcoidosis in Chinese Han subjects

Human leukocyte antigens (HLA) play a key role in antigen presentation. HLA genes, especially HLA-A, -B, and -DRB1, which are highly polymorphic, have been thought to be candidate loci for the etiology of sarcoidosis. This study aimed to assess the association between the polymorphism of HLA-A, -B, and -DRB1 alleles and sarcoidosis in Chinese Han subjects. Genomic DNA was extracted from 131 patients with sarcoidosis and 122 healthy controls. The polymorphisms of the HLA-A, -B, and -DRB1 alleles were determined using a polymerase chain reaction sequence-specific primer method. The frequency of allele HLA-DRB1*11 in sarcoidosis patients was significantly higher than that in controls (24.43% vs 4.92%, p/p(c) = 0.0001/0.002), whereas the frequencies of allele HLA-B*13 and HLA-DRB1*07 were markedly lower in sarcoidosis patients than in controls (12.21% vs 27.87%, p/p(c) = 0.002/0.045; 7.63% vs 22.95%, p/p(c) =0.001/0.009). HLA-B*51 was overrepresented in patients with erythema nodosum and Löfgren's syndrome (p < 0.001 [p(c) = 0.015], p < 0.0001 [p(c) < 0.001], respectively). These results support the hypothesis that HLA-A, -B, and -DRB1 polymorphisms may play a role in susceptibility and manifestation of sarcoidosis.

HLA class I and class II frequencies in patients with sarcoidosis from Croatia: role of HLA-B8, ?DRB1*0301, and ?DQB1*0201 haplotype in clinical variations of the disease

Sarcoidosis is an immune-mediated, multiorgan, granulomatous disease triggered by a combination of environmental and genetic factors. Numerous studies have reported about an association of human leukocyte antigen (HLA) alleles with sarcoidosis, with variation of alleles in different ethnic groups. Therefore, we investigated 142 Croatian sarcoidosis patients treated at the University Hospital for Lung Diseases Jordanovac, Zagreb, Croatia. Diagnosis was based on the presence of typical clinical features, chest X-ray findings and biopsy evidence of granuloma. Patients and control subjects (n = 190) were typed for HLA class I antigens by serology, while for HLA class II, they were tested by the polymerase chain reaction-sequence specific primers (PCR-SSP) method. Results indicated that HLA-B8, -DRB1*0301, and -DQB1*0201 positive patients have a significantly higher risk of acute onset of the disease (AOD), radiological stage I erythema nodosum (EN), Löfgren's syndrome, no-medicament therapy, and pulmonary sarcoidosis. On the other hand, the group of non-treated patients (corticosteroids and/or immunosuppressive) showed a significantly lower presence of HLA-B15 antigen in comparison to controls and treated patients (P = 0.0490 and P = 0.0379, respectively) and for DRB1*04 specificity (P = 0.0078 and P = 0.0065, respectively). In the group of patients with AOD, those who were positive for DRB1*16 specificity have a statistically significant chance to develop EN, as opposed to those who are positive for DRB1*15 specificity.

Role of HLA-B51 and HLA-B52 in susceptibility to pulmonary tuberculosis

MHC class I-restricted CD8+ T cells are important for the generation of protective immune responses in MTB infection. CD8+ CTL (cytotoxic T-lymphocyte)-derived IFN-g may be especially important both for cells lacking MHC class II molecules, e.g. in the lung and for macrophages where mycobacteria can evade recognition during chronic infection by sequestering their antigens away from sensitized CD4+ T cells. This study was designed to detect any association of MHC class I (HLA-B) molecules with pulmonary tuberculosis. A total of 75 individuals, comprising of 33 patients with pulmonary tuberculosis; 12 HIV patients who developed tuberculosis and 30 healthy controls, were included in the study. They were typed for HLA-B by the PCR-SSP method. The results of only HLA-B alleles, which are highly significant, are presented here. The number of healthy individuals with HLA-B52 was significantly high when compared to the patient groups (healthy versus TB: 21.2% versus 0.0%, OR=0.0, P<0.0001, P(c)=0.003; healthy versus HIV-TB: 21.2% versus 16.7%; OR=0.74; P<0.001; P(c)=0.003). In contrast, the number of patients, both TB- and HIV-TB-positive, with HLA-B51 was significantly high when compared to the healthy group of individuals (TB versus healthy: 36.7% versus 3%; OR=18.53; P<0.0001; P(c)=0.001; HIV-TB versus healthy: 41.7% versus 3%; OR=22.86; P<0.0001; P(c)=0.001). Only one healthy control was positive to HLA-B51; however this individual also had HLA-B52. The results of this study suggest that HLA-B52(5) has a negative, i.e. a protective association and HLA-B51(5) has a positive (susceptible) association, for pulmonary tuberculosis. Studies on HLA-B51 and HLA-B52 in a larger population to assess their role in tuberculosis may be useful for TB-vaccination strategies, since HLA profiles are likely to be related to vaccine efficacy.

[Human leukocyte antigens A and B in Turkish patients with sarcoidosis]

OBJECTIVE

Associations between human leukocyte antigens (HLA) and sarcoidosis have been reported in several studies. We aimed to investigate these associations in Turkish patients.

PATIENTS AND METHOD

We performed HLA-A, HLA-B, HLA-C, and HLA-D typing in 83 patients with sarcoidosis and in 250 healthy controls using a microlymphocytotoxicity method to investigate genetic susceptibility to the disease.

RESULTS

Because of significant violation of Hardy-Weinberg equilibrium at HLA-C and HLA-DQB1 loci, only results obtained at other HLA loci were used. Although HLA-A9, HLA-B5, and HLA-B8 allele frequencies were significantly higher in the patient group compared to the controls (odds ratio [OR]= 21.8, P= .015; OR= 9.34, P= .049; OR= 2.26, P= .031, respectively), none of the differences remained significant after applying the Bonferroni correction. HLA-A24, HLA-A26, and HLA-B62 alleles were significantly less frequent in the patient group compared to the controls (OR= 0.48, P= .018; OR= 0.19, P= .003; OR= 0.11, P= .044, respectively). However, the differences also failed to remain significant after Bonferroni correction.

CONCLUSIONS

These results suggest that both HLA may play significant roles (either increasing or reducing risk) in the pathogenesis of sarcoidosis and in its distinct clinical forms and laboratory findings.

Consideration of the risk and treatment of tuberculosis in patients who have rheumatoid arthritis and receive biologic treatments

Evidence supports the association of tuberculosis (TB) with tumor necrosis factor inhibitor therapy in patients who have rheumatoid arthritis. There seem to be differential risks of TB with the currently available inhibitors. Screening for latent TB infection with purified protein derivative is indicated for patients who are being considered for treatment; it seems to be effective in reducing the occurrence of TB in treated patients.