Disparity for the minor histocompatibility antigen HA-1 is associated with an increased risk of acute graft-versus-host disease (GvHD) but it does not affect chronic GvHD incidence, disease-free survival or overall survival after allogeneic human leucocyte antigen-identical sibling donor transplantation

Disparity for the minor histocompatibility antigen HA-1 between patient and donor has been associated with an increased risk of acute graft-versus-host disease (GvHD) after allogeneic human leucocyte antigen (HLA)-identical sibling donor stem cell transplantation (SCT). However, no data concerning the impact of such disparity on chronic GvHD, relapse or overall survival are available. A retrospective multicentre study was performed on 215 HLA-A2-positive patients who received an HLA-identical sibling SCT, in order to determine the differences in acute and chronic GvHD incidence on the basis of the presence or absence of the HA-1 antigen mismatch. Disease-free survival and overall survival were also analysed. We detected 34 patient-donor pairs mismatched for HA-1 antigen (15.8%). Grades II-IV acute GvHD occurred in 51.6% of the HA-1-mismatched pairs compared with 37.1% of the non-mismatched. The multivariate logistic regression model showed statistical significance (P: 0.035, OR: 2.96, 95% CI: 1.07-8.14). No differences were observed between the two groups for grades III-IV acute GvHD, chronic GvHD, disease-free survival or overall survival. These results confirmed the association between HA-1 mismatch and risk of mild acute GvHD, but HA-1 mismatch was not associated with an increased incidence of chronic GvHD and did not affect relapse or overall survival.

Bullous pemphigoid associated with acute glomerulonephritis

We report an 82-year-old man who presented with bullous pemphigoid and who later developed an acute glomerulonephritis with the histopathological and immunofluorescence pattern of a postinfectious glomerulonephritis. Antibodies directed against 230 and 180 kDa bullous pemphigoid antigens were detected in the patient's serum by means of the immunoprecipitation technique. Staphylococcus aureus and methicillin-resistant S. aureus were isolated from the patient's skin. We consider that in this particular patient the cutaneous infection played a part in the development of the kidney complication.

Genomic typing of minor histocompatibility antigen HA-1 by reference strand mediated conformation analysis (RSCA)

Disparities in minor histocompatibility antigen (mHAg) HA-1 are involved in the development of acute graft-versus-host disease (GvHD) in adult recipient after HLA-identical sibling donor hematopoietic stem cell transplantation. The mHAg HA-1 is an HLA-A*0201-restricted nonapeptide, which derives from the cleavage of a protein encoded at chromosome 19. The sequence analysis of HA-1 cDNA identified two alleles, termed HA-1H and HA-1R, which differ in only two nucleotides at 3' end of exon A, at positions 500 and 504. DNA-based methods for HA-1 typing were developed in 1998, using polymerase chain reaction with sequence-specific primers (PCR-SSP) and restriction fragment length polymorphism (PCR-RFLP). Here, we report the usefulness of reference strand mediated conformation analysis (RSCA), which was developed for mutation detection and typing of polymorphic loci, to discriminate between the two HA-1 alleles. We performed genomic typing of HA-1 locus in 203 HLA-A*0201-positive samples using RSCA and we confirmed these results by PCR-SSP. The results demonstrate the high reproducibility of this method and their strong correlation with the results obtained by PCR-SSP (99%). Only two samples showed disparity between the RSCA typing and the PCR-SSP. Direct sequencing of these samples confirmed that the correct allele assignment was that obtained by the RSCA typing. Furthermore, HA-1- RSCA-based typing provides additional information about the intronic structure of both alleles. With this approach, we describe the almost constant presence (99.2%) of a 5-bp deletion at intronic position 214-218 associated to the HA-1H allele, previously unidentified. We conclude that HA-1 genomic typing by RSCA is easy to perform and that could be used as a routine typing method.

HLA-B44 subtyping in the Catalan population using reference strand mediated conformation analysis. Implications for the selection of unrelated bone marrow donors

Cytotoxic T lymphocytes (CTLs) reactive against the disparity between HLA-B*4402 and HLA-B*4403 have been reported after unrelated donor bone marrow transplantation. These CTLs have been associated with acute graft-versus-host disease and graft rejection. This study describes the HLA-B44-subtyping in the Catalan population using reference-strand mediated conformation analysis. It has been performed on 297 unrelated HLA-B44+ cord blood units from the Barcelona Cord Blood Bank (Barcelona, Spain). We have found a predominance of HLA-B*4403 (66.04%) over HLA-B*4402 (33.02%), whereas the predominant HLA-B44 allele in Northern Europe and the United States is HLA-B*4402. This inverted proportion between HLA-B44 subtypes in Mediterranean populations compared with other Caucasian populations suggests that HLA-B44 subtyping should be performed when an HLA-B44+ unrelated donor marrow is identified.

Follow-up of chimerism status after allogeneic HLA-mismatched stem cell transplantation by detection of non-shared HLA alleles

BACKGROUND AND OBJECTIVES

Chimerism studies after allogeneic transplantation are usually performed using cytogenetic analysis, PCR-VNTR or PCR-STR. Here, we report an alternative method for following the chimerism status after an HLA-mismatched stem cell transplantation (SCT), detecting the presence of non-shared HLA alleles by reference-strand mediated conformation analysis (RSCA).

DESIGN AND METHODS

We tested this new approach on allogeneic related haploidentical SCT, unrelated cord blood transplantation, and HLA-mismatched unrelated donor SCT. The quantification of the chimerism was performed by laser detection of fluorescent-labeled primers on an automated DNA sequencer.

RESULTS

In all cases this technique was able to detect mixed chimeras. The technique detected above 5% of residual cells when the analysis was based on HLA-class I and above 3% for HLA-class II. This sensitivity is similar to that of the PCR-VNTR analysis.

INTERPRETATION AND CONCLUSIONS

This method avoids the need to search for an informative locus (which is essential for PCR-VNTR or -STR). Moreover, we did not find the phenomenon of preferential amplification that is observed with most VNTR, thus avoiding the need for construction of standard curves to quantify mixed chimeras. We conclude that the detection of the non-shared HLA alleles by RSCA is a useful approach for chimerism follow-up after HLA-mismatched SCT.

[Chronic monoarthritis caused by osteoid osteoma]

Osteoid osteoma is a nonmalignant tumour that rarely localizes intraarticularly. When this happens, the tumour provokes arthritis and its recognition is delayed from months to years. We report the case of a 34 year old man with a previously known HIV infection, but no evidence of immunosuppression. He develops a chronic monoarthritis of the left elbow that is initially interpreted as infectious disease. CT provides diagnostic suspicion of osteoma, that is confirmed by pathologic examination two years after the onset of the clinical complaints. CT is the radiologic technique of election in the evaluation of osteoid osteoma. Synovitis is interpreted in the literature as secondary to prostaglandin secretion by the tumour.

[Pulmonary epidermoid carcinoma in a 22-year-old patient with multiple cutaneous metastasis]

The authors present one clinical case of lung epidermoid carcinoma with several concurrent features which are uncommon in relation to this type of neoplasia. Consequently, the age of the patient (22), the lack of known risk factors, the histologic type (little differentiated squamous) and an aggressive biologic behaviour of the tumour, preceded of multiple cutaneous metastasis, are circumstances that make this clinical case exceptional. The more significative aspects present at lung carcinoma included in this age group respect to others are analyzed.