Associations between HL-A histocompatibility antigens and non-malignant diseases

Biological predictors of lithium response in bipolar disorder

In order to prescribe lithium appropriately to patients with bipolar disorder, predictors of lithium response are helpful. The present paper reviews the biological predictors of lithium response. As a positive predictor of lithium response, the following have been reported: strong loudness dependence of the auditory-evoked N1/P2-response; higher brain lithium concentration; lower inositol monophosphatase (IMPase) mRNA expression; higher serotonin-induced calcium mobilization; increased N-acetyl-aspartate peak and decreased myo-inositol peak; white matter hyperintensity; decreased intracellular pH; higher frequency of phospholipase C gamma-1 (PLCG1)-5 repeat and PLCG1-8 repeat; and C973A polymorphism in the inositol polyphosphate 1-phosphatase gene. In contrast the following have been reported as a predictor of negative lithium response: epileptiform abnormality of electroencephalography; human leukocyte antigen type A3; decreased phosphocreatine peak area after photic stimulation; and homozygotes for the short variant of the serotonin transporter gene. Most of the possible biological predictors of better lithium response, such as lower IMPase mRNA levels, white matter hyperintensity, lower brain intracellular pH, enhanced calcium response, and PLCG1-5 repeat had been detected as risk factors for bipolar disorder, suggesting that bipolar disorder responding well to maintenance lithium treatment is a distinct category having a certain neurobiological basis, although these findings need further replication. The search for biological predictors of lithium response is still in its infancy. Most of the laboratory or neuroimaging techniques used in these studies are not easily performed in clinical settings, so the development of an easy and useful laboratory test is needed.

An association study of Huntington's disease and HLA

HLA antigens were determined in a sample of 47 patients with the diagnosis and family history of Huntington's disease (HD). Two groups consisting of 20 and 11 unrelated patients respectively were investigated. In the first group an increased frequency of HLA-Bw44 (p less than 0.05) and of HLA-A11 (p less than 0.05) was found, but after correcting for multiple inferences the differences were no longer statistically significant. No correlation was found between sex, age of onset, initial symptom, and HLA type. In order to find out if the increased frequency of HLA-Bw44 was real or due to chance, the second group of patients was investigated. In this group the frequency of HLA-Bw44 did not differ from the normal population and a strong association between HLA and HD could be excluded.

HLA and alopecia areata in Jerusalem

A study of 46 patients with Alopecia areata in Jerusalem showed a significant increase in the frequency of HLA-B18 (23.9%) as compared to the control population (7.4%) with a relative risk of 3.9%. This association of HLA-B18 with AA was independent of the origin of patients, sex, age of onset and type of alopecia areata.

Role of thymectomy in the surgical treatment of myasthenia gravis

Of the 26 patients with myasthenia gravis undergone thymectomy, 11 cases had either benign or malignant thymoma as judged not only by hitological examination but also by their clinical and operative findings. Age of initial onset ranged from 13 to 64 years old. Fifteen out of 26 (58 per cent) benefited from thymectomy. Duration of the symptom from the onset to the operation and the presence or absence of the thymoma are not related to their outcome. Benign or malignant nature of thymoma should not be determined by histological examination alone but by combined evaluation of clinical and operative findings. Serial studies of serum immunoglobulin levels before and after thymectomy suggested that this disorder could be associated with humoral antibody (IgG). HLA typing of the patients with myasthenia gravis did not indicate the presence of any specific antigens.

Cystic fibrosis and HLA

In 94 children suffering from cystic fibrosis, no abnormal frequencies of HLA markers of the A and B locus were observed in comparison with the distribution of these antigens in control series. Furthermore, the HLA genotypes of seven pairs of diseased sibs are incompatible with the hypothesis of a closed linkage between CF--an autosomal recessive transmitted disease--and HLA.

Tuberculosis associated with HLA--B8, BfS in a Newfoundland community study

In three adjacent Newfoundland communities comprising some 1500 people, 589 people have been HLA typed. Forty-six of the typed people gave a history of previous clinical tuberculosis which required treatment. Fifty-six percent of the TB patients carried HLA B8 compared with 20% of the remainder of the population. This is a highly significant difference (P less than 0.01). In each community the frequency of B8 as an epidemiological marker correlated with the incidence of tuberculosis. B8 is associated with TB in ths study with a relative risk of 5.2 which compares with combined relative risks in the literature for coeliac disease and Addison's disease of 9.5 and 6.4, respectively, and which is greater than the risks for all the other B8-related diseases. The factor B allele, Bf S, was found on all the B8 haplotypes, but the overall Bf gene frequencies in tuberculosis patients did not deviate from expected values.

HLA and mycobacterial infection: increased frequency of B8 in Japanese leprosy

A total of 60 leprosy patients, 28 of lepromatous and 32 of tuberculoid form, and 70 active tuberculosis patients was compared with a control of 184 for 34 HLA specificities. The most interesting finding was an increased frequency (10.0%) for HLA-B8 (corrected P = 0.062, relative risk = 20.3) in the leprosy patients as compared with the control group, despite the fact that the frequency of HLA-B8 was extremely low in Japanese. Furthermore, all leprosy patients with B8 had leprous member(s) in their family.

HLA antigens and myxedema

In 22 cases of myxedema 22 HLA-A and B antigens were typed. In six out of eight patients with a history of subacute thyroiditis Bw35 antigen was demonstrated, while in none of 14 patients free from this disease in anamnesis could this antigen be found. This difference is statistically significant, and suggests classifying of myxedema patients into two groups according to pathogenesis of the disease.

HLA-antigen b27 in cases with joint affections in an outbreak of salmonellosis

An outbreak of infection with Salmonella typhi murium occurred in southern Sweden in the summer of 1974. About 330 persons were infected; 91 were hospitalized. 13 of the 91 patients (9 men and 4 women) had symptoms of aseptical polyarthritis. The 13 patients with arthritis were HLA typed with a standard microlymphocytotoxicity test. 13 salmonellosis patients from the same epidemic but without arthritis and 446 healthy blood donors served as controls. Nine (69%) of the 13 patients with arthritis had HLA-B27 compared to 1 (8%) of the control patients and 44 (10%) of the blood donors. The observed association between HLA antigen B27 and reactive arthropathy following salmonella infection could be due to a function of a disease predisposing gene closely linked to HLA-B27.

Association of Sjögren's syndrome with HLA-B8

HLA antigens were examined by microdroplet lymphocyte cytotoxicity in 31 patients with Sjögrens syndrome. Fifty percent of 22 Causcasian patients (7 of 17 females and 4 of 5 males) had HLA-B8, as compared to 21% of 1205 controls (P=0.002). The presence of HLA-B8 was not correlated with parotid salivary flow, keratoconjunctivitis sicca, or focus score. Because of its association with a number of autoimmune diseases, including Sjögren's syndrome, it is suggested that HLA-B8 is genetically liked to an immune response gene(s) that predisposes the individual to autoimmune phenomena. The expression of autoimmunity may be determined by infectious or environmental factors.

HL-A antigens in lichen planus

A study of fifty-seven patients with lichen planus showed a significant increase in the frequency of HL-A3 (54% compared with 29.7% in a control population). It is likely that there is a gene in the HL-A chromosomal region increasing the susceptibility to lichen planus. No correlation was found between HL-A3 and age of onset, sex, and presence or absence of mucosal lesions.

The HLA linkage group and disease susceptibility

The HLA linkage group, located on chromosome 6, is composed of serologically defined (SD-) loci (HLA-A, -B and -C) and of a MLC (= mixed lymphocyte culture-) or lymphocyte defined (LD-) locus (HLA-D). Different alleles of these loci are linked together as well as with loci for the synthesis of some complement components and the properdin factor B (= Bf-system) by strong positive linkage disequilibria (gametic association). The indication of a HLA linked genetic control of immunoresponsiveness makes the HLA system one of the biologically most important immunogenetic systems in man. The associations, found between single HLA determinants and diseases, can be explained in different ways, but may contribute to a better understanding of the etiopathogenesis of diseases and of the biological role of the HLA linkage group.

The HL-A7 histocompatibility antigen in sarcoidosis in relation to tuberculin sensitivity

Eighty cases of sarcoidosis have been investigated. In all except eight patients a histological verification of the diagnosis was obtained by mediastinoscopy or liver biopsy. The HL-A7 antigen was not increased in the entire group. However, in the group of patients with a negative sensitivity to tuberculin after the appearance of the disease there was a significant increase compared with controls. In the patients with a positive reaction, there was a complete absence of HL-A7. The HL-A system therefore does not seem to influence the liability to contract sarcoidosis, but once this condition has developed HL-A7 positives are more likely to lose cellular immunity to tuberculin and to reveal symptoms.