Detection of antibodies to HIV-1 gp41- and HLA class II antigen-derived peptides in SLE patients

IgM Repertoire Biodiversity is Reduced in HIV-1 Infection and Systemic Lupus Erythematosus

Background: HIV-1 infection or systemic lupus erythematosus (SLE) disrupt B cell homeostasis, reduce memory B cells, and impair function of IgG and IgM antibodies.

Objective: To determine how disturbances in B cell populations producing polyclonal antibodies relate to the IgM repertoire, the IgM transcriptome in health and disease was explored at the complementarity determining region 3 (CDRH3) sequence level.

Methods: 454-deep pyrosequencing in combination with a novel analysis pipeline was applied to define populations of IGHM CDRH3 sequences based on absence or presence of somatic hypermutations (SHM) in peripheral blood B cells.

Results: HIV or SLE subjects have reduced biodiversity within their IGHM transcriptome compared to healthy subjects, mainly due to a significant decrease in the number of unique combinations of alleles, although recombination machinery was intact. While major differences between sequences without or with SHM occurred among all groups, IGHD and IGHJ allele use, CDRH3 length distribution, or generation of SHM were similar among study cohorts. Antiretroviral therapy failed to normalize IGHM biodiversity in HIV-infected individuals. All subjects had a low frequency of allelic combinations within the IGHM repertoire similar to known broadly neutralizing HIV-1 antibodies.

Conclusion: Polyclonal expansion would decrease overall IgM biodiversity independent of other mechanisms for development of the B cell repertoire. Applying deep sequencing as a strategy to follow development of the IgM repertoire in health and disease provides a novel molecular assessment of multiple points along the B cell differentiation pathway that is highly sensitive for detecting perturbations within the repertoire at the population level.

Expression of human endogenous retrovirus clone 4-1 may correlate with blood plasma concentration of anti-U1 RNP and anti-Sm nuclear antibodies

The transcription of human endogenous retrovirus E (HERV-E) clone 4-1 was determined in peripheral blood mononuclear cells (PBMC) of patients with systemic lupus erythematosus (SLE). However, the contribution of HERV-E clone 4-1 expression in the development of SLE remains unclear. Blood plasma and PBMC from 55 patients with SLE and a control group of 35 healthy individuals were collected. Blood plasma concentration of five antinuclear antibodies including anti-U1 ribonucleoprotein (RNP), anti-Sm, anti-Scl-70, anti-single-stranded DNA (ssDNA), and anti-double-stranded DNA (dsDNA) was analyzed by enzyme-linked immunosorbent assay (ELISA). Total RNA was isolated from PBMC and reverse transcribed into cDNA. The number of copies of HERV-E clone 4-1 gag transcript in PBMC was determined by real-time quantitative polymerase chain reaction (RQ-PCR) analysis. Spearman statistical analysis indicated that blood plasma concentrations of anti-U1 RNP and anti-Sm antibodies may correlate with PBMC transcript levels of HERV-E clone 4-1 gag sequence (R = 0.775, p < 0.000001; R = 0.698, p < 0.000001, respectively). Our observations suggest that the expression of HERV-E clone 4-1 might be associated with production of anti-U1 RNP and anti-Sm antibodies in patients with SLE.

Autoantibody explosion in systemic lupus erythematosus: more than 100 different antibodies found in SLE patients

OBJECTIVE

Description of the various autoantibodies that can be detected in patients with systemic lupus erythematosus (SLE).

METHODS

A literature review, using the terms "autoantibody" and "systemic lupus erythematosus", was conducted to search for articles on autoantibodies in SLE, their target antigens, association with disease activity, or other clinical associations.

RESULTS

One hundred sixteen autoantibodies were described in SLE patients. These include autoantibodies that target nuclear antigens, cytoplasmic antigens, cell membrane antigens, phospholipid-associated antigens, blood cells, endothelial cells, and nervous system antigens, plasma proteins, matrix proteins, and miscellaneous antigens. The target of autoantibody, the autoantigen properties, autoantibody frequencies in SLE, as well as clinical associations, and correlation with disease activity are described for all 116 autoantibodies.

CONCLUSIONS

SLE is the autoimmune disease with the largest number of detectable autoantibodies. Their production could be antigen-driven, the result of polyclonal B cell activation, impaired apoptotic pathways, or the outcome of idiotypic network dysregulation.

Identification of retroviral conserved pol sequences in serum of mixed connective tissue disease and systemic sclerosis patients

Human endogenous retroviruses (HERVs) expression has been suspected as a factor participating in the development of autoimmune diseases. Employing the dot blot hybridisation, we observed that 90.9% of mixed connective tissue disease (MCTD) (n = 22) patients exhibited the presence of human immunodeficiency virus type 1 (HIV-1) conserved pol sequence in DNA isolated from serum. The same investigation conducted in the group of systemic sclerosis (SSc) (n = 79) patients identified a conserved retroviral pol sequence in 34.6% of antinuclear antibodies (ANA) positive (n = 52) and 40.7% of ANA negative (n = 27) patients. However, 100% of anti-U1-ribonucleoprotein (RNP) positive SSc (n = 9) patients exhibited the presence of HIV-1 conserved pol sequence. Our findings suggest that the presence of retroviral sequence in serum of MCTD and SSc patients may correlate with development of autoimmune response directed against U1-70 kDa polypeptide antigen.

Lessons from similarities between SLE and HIV infection

OBJECTIVE

We attempted to obtain deeper understanding of systemic lupus erythematosus (SLE) and human immunodeficiency virus (HIV) infection through comparative studies between both diseases.

METHOD

For this purpose, we reviewed and discussed lessons from similarities in both diseases based on our own and reported findings in literatures.

RESULT

Such comparative studies may contribute to the progress in understanding the clinical or pathogenetic features of these diseases.

CONCLUSION

Further studies into the relationship between SLE and HIV infection may bring to light important clues to assist in the development of better treatments for each disease.

Sequence analysis of human endogenous retrovirus clone 4-1 in systemic lupus erythematosus

Human endogenous retroviruses (HERV) have emerged as a possible cause of systemic lupus erythematosus (SLE). We previously detected serum antibodies to the gag region of HERV clone 4-1 in patients with SLE, but not in normal volunteers. In the present study, we detected clone 4-1 messenger RNA (mRNA) in peripheral blood mononuclear cells (PBMC) from SLE patients and performed sequence analysis of the cDNA or genomic DNA from clone 4-1 in these patients. Clone 4-1 mRNA was detected in all of the SLE patients tested, although it was not found in normal controls. Sequence analysis of clone 4-1 in these SLE patients revealed inactivation of the stop codons in part of the gag region. In addition, a computer search of current sequence libraries revealed that the clone 4-1 gag genomic DNA from SLE patients was more highly homologous with the clone 4-1 sequence in chromosome 11 from normal individuals when compared with the sequence of clone 4-1 integrated in the other chromosomes. It is possible that transcription of clone 4-1 from chromosome 11 occurs in SLE, and that the stop codon inactivation contributes to the translation of clone 4-1 gag proteins in patients with this disease.

Exacerbation of systemic lupus erythematosus related to cytomegalovirus infection

We report two patients with systemic lupus erythematosus (SLE) in whom cytomegalovirus (CMV) infection may have played a significant role in the exacerbation or onset of symptoms. The first patient had thrombocytopenia and the second had proteinuria. CMV infection was observed in both patients when their symptoms developed.

The HIV/AIDS epidemic: its evolutionary implications for human ecology with special reference to the immune system

The epidemiology of AIDS in Africa is discussed. Serological and clinical data on virology and population genetics are related to current theories of heterosexual transmission and to cultural practices involving the exchange or transmission of body fluids between individuals, such as female and male genital mutilation and indigenous or 'folk' medicine, as well as non-Western medical uses of medical syringes. A review of the relationship of autoimmune conditions, graft-vs-host disease and the retrovirus/oncogene involvement is presented. These data place in a new perspective concepts of widespread heterosexual infection and transmission of HIVs as well as their relation to AIDS in the context of the evolution of the human immune system.