HLA-DR3 and immunoresponsiveness

[CD8 hyperlymphocytosis syndrome and human immunodeficiency virus infection: 5 cases]

A retrospective study on 202 consecutive patients with HIV infection was reviewed. A particular syndrome with blood CD8 lymphocytosis > 1 500/mm3, associated with a diffuse lymphocytic infiltrate histologically proved in the tissue of different organs was present in five patients. Clinical findings were variable, depending on the location of visceral infiltrate by activated, polyclonal lymphocytes of CD8 phenotype: interstitial pneumonia (n = 3), parotid gland enlargement with sicca syndrome (n = 2), pseudo-tumoral splenomegaly (n = 1), peripheral neuropathy (n = 1), superficial generalized lymphadenopathy (n = 5). This syndrome occurred early during HIV infection. All patients had a blood CD4 lymphocyte count > 200/mm3. This disorder is a host immune response, sometimes associated with the presence of some HLA antigens: HLA-DR5 or HLA A1 B8 DR3. Whether this immune response is specific or not, whether outcome of HIV infection depends on hyper CD8 lymphocytosis remains to be proved.

Diabetes can be prevented by reducing insulin production

Hypersecretion of insulin increases the chance of the incidence of diabetes type I and II, while inhibiting insulin secretion helps prevent diabetes. Trace elements like zinc and vanadium prevent hyperinsulinemia, partly because of their own insulin activity, which is also a property of interleukin-1 (IL-1), particularly during periods of illness and stress. Like vanadium, IL-1 can replace insulin for many hours and regulate glucose metabolism. Vanadium, zinc and IL-1 ensure that insulin-producing beta-cells in the pancreas do not lose too much zinc, which leaves the beta-cells together with insulin. Zinc forms a complex with metallothionein in beta-cells that provides protection against free (oxygen) radicals, which become active during immune responses triggered by bacteria and viruses, for instance. In addition, zinc is the only non-toxic trace element in the body that regulates concentration-dependent immune responses on many levels. Avoiding deficiencies of trace elements will enable the reduction of the incidence of diabetes.

HLA-B8,DR3 phenotype and the antibody response against Epstein-Barr virus

Antibodies against the viral capsid antigen (VCA) and nuclear antigens (EBNAs) of the Epstein-Barr virus (EBV) were determined in a sample of Sicilian population. A significant correlation was observed between HLA-B8,DR3 phenotype and reduced titres of antibodies to EBNAs, whereas HLA-B8,DR3 positive individuals displayed levels of antibodies to VCA comparable to those of HLA-B8,DR3 negative ones. These results further strengthen the suggestion that HLA-B8,DR3 positive subjects are low responders and that the depth of immune response depends on the fashion of antigenic challenge.

Transient IgG subclass deficiencies in newly diagnosed diabetic children

In 27 children (15 males and 12 females) with insulin-dependent diabetes mellitus (IDDM), aged 1.2-13.5 years (mean 9.9 +/- 3.6 years) we investigated immunoglobulins (IgG, IgA, IgM), IgG subclass levels and islet-cell antibodies (ICA) at diagnosis and at 6 and 12 months after disease onset. At diagnosis, IgG levels were lower than -2SD in 7 patients (26%), IgA in 1 (3.7%), IgM in 1 (3.7%). IgG subclass levels were below the 3rd percentile in 13 patients (48.1%); in particular IgG1 in 7 (26%), IgG2 in 3 (11.1%), IgG3 in 2 and IgG4 undetectable in 1 case. In 3 out of the 13 patients combined IgG1-IgG3, IgG1-IgG2 and IgG1-IgG4-IgA deficiencies were observed. ICA were greater than 20 Juvenile Diabetes Foundation units in 17/27 patients. The HLA-DR2 frequency was higher in patients with IgG subclass deficiency than in patients with normal IgG subclass levels. During follow up, IgG levels normalized in 6 patients while IgA and IgM did not change. IgG1 normalized in 5 out of the 7 patients, IgG2 in all patients while IgG3 and IgG4 did not change. One year later ICA were still present in 8/27 patients. The hypogammaglobulinaemia and IgG subclass deficiencies observed in our patients could have either a genetic or an acquired basis.

Soluble interleukin-2 receptor release defect in vitro in elderly subjects

The evidence from several studies indicates that as individuals age, they may display immune dysfunctions, mostly T cell dysfunctions. Recently, a soluble form of the receptor for interleukin-2 (IL-2) (sIL-2R) has been demonstrated in human sera and in vitro stimulated culture supernatants from human T lymphocytes. In the present paper, we report in vitro sIL-2R production from peripheral blood mononuclear cells in elderly subjects. The results show that no difference exists for unstimulated cultures, whereas after mitogen stimulation the elderly subjects showed the lowest values compared with young ones. These findings suggest that sIL-2R may provide a new tool for the study of T lymphocyte dysfunctions in old age.