Correlations between insulin antibodies and the HLA system in a group of type I diabetic patients in Bucharest.

Investigations were carried out in Bucharest in 102 patients with insulin-dependent diabetes mellitus (IDDM) in order to verify the possible existence of a relationship between the HLA system and the level of insulin antibodies. The A and B loci were tested with monospecific antisera, using PEC as a separation agent for the determination of the insulin antibody titer. Group I, without antibodies (34 cases), presented: HLA-B7 (18.89% of total specificities), A3 (11.02%), A1 and B5 (8.74% each), etc.: for haplotypes the following were found: HLA-A3/B7 (9.91% of the total haplotypes), A2/B7 (8.26%), A1/B7 (5.78%). Group II (50 cases) with low or medium titers (less than 30% binding) included: HLA-B7 (20.47%), A2 (11.88%), (A1 (9.44%), B5 (8.74%), and haplotypes: HLA-A2/B7 (8.88%), A1/B7 (7.22%), A3/B7 (6.11%). Group III (18 cases), with high antibody titers (greater than 30% binding), presented: HLA-B7 (20.28%), A1 and A2 (11.59% each), A10 (10.14%), and haplotypes: HLA-A1/B7 (10.60%), A2/B7 and A10/B7 (9.09% each), A3 B7, A2 B5 and A10/B5, (6.06% each). Irrespective of the insulin antibody titer, B7 antigen surprisingly appeared predominant in our cases. Moreover, a marked tendency of A1, and to a certain extent of A2, to increase in terms of the titer was noted in parallel with a significant decrease of A3.

Testing histocompatibility antigens (loci A and B) in a group of type 1 (insulin-dependent) diabetic patients in Bucharest.

For a preliminary estimation of the prevalence and significance of HLA antigens, tests were carried out on the A and B loci in an unselected group of 107 patients with type 1 diabetes in Bucharest. Monospecific antisera furnished by NIH, Bethesda were used. For HLA-A the following data were obtained: A2 (20.3% of the total specificities); A1 (18.4%); A3 (14.0%); A28 (10.1%). Provisional estimations in the healthy population also indicated HLA-A2 as being more frequent than followed by A30/31, A1, A9, A3. For HLA-B: B7 (38.2%); B5, B12 and B14 (14.0% each); B8 (11.1%). In the healthy subjects, the order was B12, B35, B5, B8 the same as B18, then B7 (which did not exceed 11%). The most frequently encountered haplotypes in the diabetic patients were: A2/B7 (8.4% of the total haplotypes); A3/B7 (6.9%); A1/B7 (6.6%); A10/B7 (3.8%); A9/B7 and A11/B7 (3.6% each). An unexpectedly high frequency of the HLA-B7 antigen was found in group of diabetic patients investigated, contrasting with its assumed "protector" role in the Caucasian population. The frequency of antigen HLA-A3 and haplotype HLA-A3/B7 infringes their listing in the "resistance axis" to diabetes.

Variation of the HL-A antigens during neoplasm evolution.

The study deals with the tissue antigen frequency in a group of 1648 patients with different clinical forms of cancer, hospitalized in the Oncological Institute, Bucharest. The authors do not find a correlation between a tissue antigen predominance and the occurrence or development of a certain form of cancer. Nevertheless a loss of some tissue antigens was noticed in severe advanced cases with multiple metastases. This fact can be observed also in patients irradiated during serotypings or treated with cortisone. At least 5 weeks after irradiation or in patients with favourable response to the treatment, with temporary important remission, the recurrence of the histocompatibility antigens can be obtained in subsequent examinations.