β - 2 - Microglobulin. Part of the HL-A Molecule in the Cell Membrane

Human lymphocytes were reacted with antisera against β-2-microglobulin (β-2-m) or HL-A antigens, and with xenogeneic anti-lymphocyte sera under conditions where redistribution and aggregation of the corresponding cell-membrane components were induced. The results demonstrate that:

• 1) 

  Treatment with anti-β-2-m antisera aggregated and completely removed the HL-A anti-genic structures from the cell membrane, but not, however, the structures reactive with anti-lymphocyte sera.
• 1) 

  Treatment with anti-HL-A antisera also aggregated some of the β-2-m carrying structures, but left others undisturbed.
• 1) 

  Treatment with anti-lymphocyte sera did not disturb expression of HL-A antigens or β-2-m structures.
• 1) 

  Anti-β-2-m and anti-HL-A antisera inhibited antigen activation of lymphocytes, but this was not so in the case of the anti-lymphocyte sera used.
• 1) 

  The anti-β-2-m antiserum and the anti-lymphocyte sera were mitogenic for normal lymphocytes.

Taken together, our results strongly suggest that β-2-m is also part of native cell-membrane bound HL-A antigens, and that the antigenic structures which react with xenogeneic anti-lymphocyte sera may reside on molecules separate from those carrying HL-A and β-2-m activity. Furthermore, the results indicate that the two sub-unit molecules consisting of HL-A alloantigenic determinants and β-2-m are closely associated — structurally or functionally — with lymphocyte receptor structures.     

Cohen syndrome: the clinical symptoms and stigmata at a young age

We present the clinical findings and follow-up data of four female children with Cohen syndrome, two sisters and one pair of dizygotic female twins. The most characteristic findings from birth on were as follows:

• 1. 

  Low-normal growth parameters at birth.
• 2. 

  Mild hypotonia and evidence of progressive microcephaly with narrow forehead in the first year of life.
• 3. 

  Neutropenia was present from the beginning, remained unchanged over the years and is not associated with higher susceptibility to infections.
• 4. 

  Autistic behavior and severe psychomotor retardation up to the age of 2 years. At that age the ocular anomalies with high-grade myopia and chorioretinal dystrophy were diagnosed. Correction of the myopia resulted in a marked catch-up in psychomotor development.
• 5. 

  After the age of 6 years facial stigmata became more evident with short philtrum of the upper lip and broad and large upper incisors.
• 6. 

  Tendency to truncular obesity with rest hypotonia and poor muscle development after the ages of 6 to 8 years.

The clinical findings and follow-up data in the present four children with Cohen syndrome illustrate that the diagnosis of Cohen syndrome in infancy is very difficult.     

HISTOCHEMICAL STUDIES ON ACHD MUCOPOLYSACCHARIDES

Some new methods for demonstration and differentiation of acid mucopolysaccharides were described.

• 1) 

  Cationic surfactive resin-azo dye method could be used for all kinds of acid mucopolysaccharide demonstration.
• 2) 

  Neutral red method was found to differentiate sulfated and non-sulfated groups on one section.
• 3) 

  Two principles to identify keratosulfate in mesenchymal tissues were studied;

• (1) 

  Hyaluronidase-methylation-saponification method can differentiate keratosulfate B which are both sensitive to testicular hyaluronidase.
• (2) 

  Sugar reactions: Molisch reaction, carbazol-sulfuric acid reaction, etc. can demonstrate the presence of galactose-containing keratosulfate in the frozen sections.

By using these together with well established methods a differential table was made.
The author is deeply grateful to Dr. SHIDA and Dr. KUSHIDA of the General Institute for Medical Biochemistry, Kyoto, Kowa Co., Kaken Yakukako Co., and Hodogaya Chemical Industry Co. for the supply of several kinds of samples.     

The atopy trait in hypersensitivity to nonsteroidal anti-inflammatory drugs

The prevalence of atopy was evaluated in two groups of subjects with hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAID):

• 1)

  78 patients with aspirin-induced asthma (AIA) confirmed by oral or bronchial provocation challenges
• 2)

  42 subjects with hypersensitivity to pyrazolone drugs (case history and positive skin tests to noramidopyrine/aminophenazone) who tolerated aspirin well.

Fifty sex- and age-matched persons from an unselected general population, with no hypersensitivity to NSAID, formed the control group. Atopy was estimated from the results of the following clinical and biologic parameters:

• 1)

  personal and family history of atopic diseases
• 2)

  skin prick tests with 16 aeroallergens
• 3)

  serum levels of specific IgE to five aeroallergens
• 4)

  total serum IgE level.

Different definitions of atopy were used, consisting of constellations of two or three of the above-mentioned features. The results of the study revealed that the prevalence of atopy varied according to the criteria used for its definition. Irrespective of the definition used, a similar distribution of atopy was observed in both groups of patients with hypersensitivity to NSAID. Atopy was more frequent in either group of patients with intolerance of NSAID than in the control group. Thus, atopy is related to adverse drug reactions to NSAID.     

Natural selection associated with birth weight I. Selection intensity and selective deaths from birth to one month of life

Differential mortality as a function of birth weight was studied up to the 4th week of life in all single births in Italy in 1974.

• (i) 

  Both selection intensity and selective mortality are much higher with increasing immaturity.
• (ii) 

  For babies born at term or after 8 months of pregnancy selection intensity tends io relax as early as one week after birth, while for those born after 7 months selection is at work for a longer period.
• (iii) 

  Selective mortality, on the other hand, keeps increasing after birth but its relevance is relatively decreasing since average mortality after birth continues to decrease.

     

Cytogenetic studies on cultured fibroblast-like cells derived from basal cell carcinoma tissue

Chromosomal investigations were performed on fibroblast cultures established from tumour tissue of six patients with multiple basal cell carcinoma, and from one patient with a solitary basal cell carcinoma. In four instances, fibroblast cultures from specimens of unaffected skin areas Were examined simultaneously. Metaphases of peripheral blood lymphocytes were analysed in all patients. Three individuals showed increased rates of chromosomal breakage and rearrangement; the possibility of a relationship between these findings and the Occurrence of multiple basal cell carcinoma is discussed:

• 1). 

  The chromosomal aberrations noted in one patient with multiple arsenic-induced basal cell carcinoma probably reflect the long-term effect of exposure to arsenic.
• 2). 

  In the second case, the aberrations found in cultures from unaffected skin and blood lymphocytes may be due to repeated X-ray therapy of multiple nevoid basal cell carcinoma
• 3). 

  In the third patient, likewise affected by multiple nevoid basal cell carcinoma, the etiology of the increased frequency of chromosomally altered cells remains obscure. Taken together with two other observations (Happle et al. 1971, Happle & Kupferschmid 1972), the aberrations could indicate that in some patients with nevoid basal cell carcinoma syndrome the incidence of spontaneous chromosomal breakage tends to increase.

     

Age at symptom onset and distribution by sex and symptoms in patients sensitized to different allergens

The aim of our study was to analyze the clinical features, particularly the age at symptom onset, of allergic subjects (asthma and/or rhinitis) on the basis of the etiologic elements (sensitization to various allergens). We identified a group of monosensitized patients and a group of polysensitized patients. Within these groups, we identified subgroups of subjects monosensitized to one of the five main allergenic mixes (mites, Gramineae, trees, Parietaria, and Artemisia) and five subgroups of patients sensitized nonexclusively, that is, polysensitized, to the same allergens. The comparison between the two groups and among the various subgroups enabled us to conclude that:

• 1)

  mono- and polysensitized patients present some clinical features so different as to constitute two clearly distinct clinical groups
• 2)

  analysis of the clinical features associated with the sensitization to a specific allergen brings us to significantly different conclusions when we consider subgroups of monosensitized or polysensitized patients
• 3)

  the parameter "age at symptom onset" shows great heterogeneity among both the mono- and the polysensitized subgroups - in particular, the great differences in mean age among the monosensitized subgroups (trees>y4rtemi.s(fl>Pflrie/flria>Gramineae>mites) appear very interesting and are open to various interpretative hypotheses
• 4)

  unlike the polysensitized group, in the monosensitized group and subgroups, mean age is similar between men and women and, only for tree- and parietaria -monosensitive patients, also between asthmatic and rhinitic subjects.

     

Electron Microscopic and Histochemical Studies on Vacuolar Alteration of Proximal Convoluted Tubules of Rat Kidney after Hypertonic Sucrose Administration

Changes of the proximal convoluted tubular epithelium of the rats which were sacrificed instantaneously at 5, 15, 30 minutes, 1, 3, 6, and 8 hours after intraperitoneal injections of 40 to 52 cc per kg of a 50 % aquenous solution of sucrose, were observed by electron microscopic and histochemical methods. The results obtained can be summarized as follows:

• 1) 

  The vacuoles begin to appear 15 minutes after the injection in the apical portion of the tubular cytoplasm and become distinct in 30 minutes. After 6 hours, it is observed in the entire cytoplasm which is filled with large vacuoles.
• 2) 

  The vacuoles originate from dilatation of simple pinocytotic vesicles which exist physiologically beneath the brush border microvilli. The small vacuoles of 1 to 1.5 microns in diameter reveal heavy acid phosphatase activity and have temporarily a character of so-called lysosome or cytosome. With the enlargement of vacuoles, the surrounding single limiting membrane reveals discontinuity or rupture at numerous sites. At this stage, the vacuoles aggregate and fuse with each other to form larger ones of 4 to 4.5 microns in diameter and lose their acid phosphatase activity.
• 3) 

  Vacuolar alteration of the proximal convoluted tubules and the role of lysosome and FCD are discussed.

     

Effects of various vacuum cleaners on the airborne content of major cat allergen (Fel d 1)

Background It has been shown that a vacuum cleaner (VC) can increase airborne cat allergen levels. This study aimed to compare the degree of leakage of airborne Fel d 1 levels among five different VCs, both under laboratory conditions and in an apartment with cats.
Methods Three of the VCs were marketed as antiallergic: a HEPA filter VC (VC A), a water impingement and HEPA filter VC (VC B), and a foam fabric filter VC (VC C). The other two were standard VCs: VC D and VC E. VCs were tested in a 20 m', airtight, experimental room and in a 53 m²* living room in an apartment with three cats. Air was sampled with a glass-fiber filter and an impinger at 20 1/min for 30 min before, during, and after vacuuming. Airborne Fel d 1 was measured with a two-site monoclonal ELISA assay.
Results In the experimental room, no airborne Fel d 1 level was measured before using the VCs. After introducing a dust sample containing Fel d 1 in the VCs. we found that VCs A, B, and E did not provoke any increase in airborne Fel d I. In contrast, VCs C and D significantly increased airborne Fel d 1 levels (GM: 4.9 and 5.3 ng/m, respectively). In the apartment, all VCs induced an increase in airborne Fel d 1, which was carried by particles greater than 5 nm. However, VCs C and D provoked significantly greater increases in airborne Fel d 1 than VCs A, B, and E (P=0.0001).
Conclusions Our results suggest that:

• 1)

  The two VCs with leakage in the experimental room had greater leakages in the apartment.
• 2)

  In the apartment with cats, all VCs provoked increases in airborne Fel d 1, primarily carried by large particles.
• 2)

  Given the increased marketing of "antiallergic" VCs, further studies are needed to standardize methods for testing airborne allergen leakage by VCs.

     

HLA haplotype study of 53 juvenile insulin-dependent diabetic (I.D.D.) families

Fifty-three families with at least one IDD patient were genotyped for 5 markers of the HLA complex including Bf and DR. In 8 families one of the parents was also affected and in 12 families more than two children were diseased. In total, 76 patients were genotyped. Their haplotypes were compared with those of 106 unrelated controls (the parents of 53 genotyped families).

• 1) 

  Three haplotypes or segments of them (A2, Cw3, B15, BfS, DR4; Aw30, Cw5, B18, BfF I, DR3; and Al, Cw7, B8, BfS, DR3) were found more frequently in IDD patients.
• 2) 

  Measured by the 6 formula, the association of the postulated IDD susceptibility gene was very strong with the D-end of two of these haplotypes: BfF1, DR3 and BfS, DR4. However, the association was weak with the DR3 of the haplotype Al, Cw7, B8, BfS, DR3.
• 3) 

  An excess of HLA-identical affected siblings was found.
• 4) 

  An excess of DR3/DR4 heterozygotes was observed. By contrast, the observed frequency of patients homozygous for DR3 or DR4 was not increased, but even slightly decreased.

The data support a model of inheritance comprising at least two closely linked specifically "diabetic" loci (most of the time marked by B18, BfFl, DR3 and B15, BfS, DR4) and a non-specifically "diabetic" haplotype favouring auto-immunisation (most of the time marked by B8, BfS, DR3). This model is discussed in the light of the presented data and of those of the literature.     

On the dynamics of HLA-A2 antigen-antibody complexes on the cell membrane of human peripheral blood lymphocytes. A biochemical and electron microscopical autoradiographic study

This report deals with some dynamic aspects of membrane bound immune complexes of HLA antigens and antibodies. Radiolabelled HLA antibodies were used to sensitize peripheral blood lymphocytes. Upon in vitro incubation of these cells, two different events were detected:

• 1) Immune complexes and a limited amount of free antibody were shed into the culture supernate; from the immune complexes specific antibodies could be regenerated.

• 2) Immune complexes were also internalized by means of endocytosis as visualized by electron microscopical autoradiography. Antibodies were found above dense bodies (lysosomes) and above multivesicular bodies.

The results are discussed in relation to the biology of membrane bound HLA molecules.     

Recent insights into the signals that control αβ/γδ-lineage fate

Summary:  During thymopoiesis, two major types of mature T cells are generated that can be distinguished by the clonotypic subunits contained within their T-cell receptor (TCR) complexes: αβ T cells and γδ T cells. Although there is no consensus as to the exact developmental stage where αβ and γδ T-cell lineages diverge, γδ T cells and precursors to the αβ T-cell lineage (bearing the pre-TCR) are thought to be derived from a common CD4⁻CD8⁻ double-negative precursor. The role of the TCR in αβ/γδ lineage commitment has been controversial, in particular whether different TCR isotypes intrinsically favor adoption of the corresponding lineage. Recent evidence supports a signal strength model of lineage commitment, whereby stronger signals promote γδ development and weaker signals promote adoption of the αβ fate, irrespective of the TCR isotype from which the signals originate. Moreover, differences in the amplitude of activation of the extracellular signal-regulated kinase- mitogen-activated protein kinase-early growth response pathway appear to play a critical role. These findings will be placed in context of previous analyses in an effort to more precisely define the signals that control T-lineage fate during thymocyte development.     

Thymic differentiation of TCRαβ+ CD8αα+ IELs

Summary:  Intraepithelial lymphocytes (IELs) contain several subsets, but the origin of the T-cell receptor (TCR)αβ⁺ CD8αα⁺ IELs has been particularly controversial. Here we provide a synthesis, based on recent work, that attempts to unify the divergent views. The intestine has a primordial function in lymphopoiesis, and precursors with the potential to differentiate into T cells are found both in the epithelium and underlying lamina propria. Moreover, the thymus has been reported to export cells to the intestine that are not fully differentiated. TCRαβ⁺ CD8αα⁺ IELs can differentiate in the intestine from each of these sources, but in normal euthymic mice, the thymus appears to be the major source for TCRαβ⁺ CD8αα⁺ IELs. This unique IEL subset is a self-reactive population that requires exposure to self-agonists for selection in the thymus, similar to other regulatory T-cell populations. IELs transition through a double-positive (DP) intermediate in the thymus, but they originate from a subset of the DP cells that can be identified by its expression of CD8αα homodimers. The agonist-selected cells in the thymus are TCRβ⁺ but CD4 and CD8 double negative. The evidence suggests that reacquired expression of CD8αα and downregulation of CD5 occur after thymus export, perhaps in the intestine under the influence of interleukin-15. As a result of agonist exposure, a new gene expression program is activated. Therefore, the increased understanding of the developmental origin of TCRαβ⁺ CD8αα⁺ IELs may help us to understand how they participate in immune regulation and protection in the intestine.     

γδ T-Cell Precursor-Derived CD4− CD8−αβ T Cells Retain γδ Cell Function

We have previously shown that some of the DNαβ⁺ T cells arising in TcRα-chain transgenic mice are of γδ T cell origin, based on phenotypic data and on their status of TcR gene rearrangements. In the present report we investigated the impact of αβ TcR expression on the functional programme of the mature γδ precursor-derived DNαβ⁺ T cells. Our results demonstrate that both their proliferative capacity and their cytokine production profile are similar to that of γδ T cells. Furthermore, both transgenic DNαβ⁺ T cells and DNγδ⁺ T cells up-regulate CD8α expression after activation, but, in contrast to CD4⁺αβ T cells, are unable to induce proliferation of naive B cells. Thus, our results suggest that the effector functions of mature T cells are determined independently of the TcR isotype, probably at an early stage of differentiation, and thereby have important implications for current models of T-cell lineage commitment.     

CD8alpha+beta(low) effector T cells in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder characterized by the loss of self-tolerance to nuclear antigens. Aberrant T-cell function plays a central role in lupus pathogenesis. We and others previously demonstrated that peripheral TCRαβ⁺CD3⁺ T cells express CD8β either at a high (CD8β^high) or low density (CD8β^low), thereby defining two functionally distinct subsets. CD8β^low T cells express predominantly CD8αα and less CD8αβ as a coreceptor, display a differentiated phenotype and exert effector function. CD8β^high T cells appear to be the precursors expressing predominantly the heterodimeric efficient CD8αβ coreceptor, exhibiting a naïve phenotype and high proliferative capacity. In the present study, the distribution and functional properties of CD8β^high and CD8β^low T cells of SLE patients were compared ( n  = 20) with those of healthy subjects ( n  = 16). It was found that expansion of CD8β^low T-cell subset correlated with disease activity indicating chronic antigenic stimulation leading to a major lack of naïve CD8β^high precursor T cells in SLE. Functional characteristics of CD8β^low T cells including production of cytokines and cytotoxic granules were not significantly different between patients with SLE and healthy individuals. We speculate that unbalanced CD8β^high/CD8β^low T-cell relation reflects a skewed homeostasis within the CD8⁺ T-cell compartment towards fully differentiated effector T cells possibly due to persistent antigen stimulation in SLE.     

γδ T cells: firefighters or fire boosters in the front lines of inflammatory responses

Summary:  Intradermal inoculation of cloned self-reactive αβ T cells into the footpads of mice induced cutaneous graft-versus-host disease (GVHD), and after recovery from GVHD, the epidermis became resistant to subsequent attempts to induce GVHD. Resistance to GVHD was not induced in the epidermis of T-cell receptor δ-deficient (TCRδ^−/−) mice that lacked γδ T cells bearing canonical Vγ5/Vδ1⁺γδTCRs, known as dendritic epidermal T cells (DETCs), and resistance was restored by reconstitution of these mutant mice with precursors of Vγ5⁺ DETCs. Pulmonary infection by Cryptococcus neoformans induced an increase of γδ T cells in the lung, and in comparison with wildtype mice, TCRδ^−/− mice eliminated C. neoformans more rapidly and synthesized more interferon-γ in the lung. In the mouse small intestine, the absence of γδ T cells is associated with a reduction in epithelial cell turnover and downregulation of the expression of major histocompatibility complex class II molecules. The protective role of γδ T cells was verified in a dextran sodium sulfate-induced inflammatory bowel disease (IBD) model, whereas in a spontaneous model of IBD, γδ T cells were involved in the exacerbation of colitis in TCRα^−/− mice. Taken together, in addition to the homeostatic regulation of epithelial tissues, γδ T cells appear to play a pivotal role in the modification of inflammatory responses induced in many organs containing epithelia.     

Oestrogen Treatment Depletes Extrathymic T Cells from Intestinal Lymphoid Tissues

Different lineages of thymic and extrathymic T cells are found in the epithelial layer and in the lamina propria of the small and large intestine of euthymic and athymic mice. A single subcutaneous injection of oestradiolvalorat (Progynon^®-Depot-10, Schering, Berlin, Germany) into athymic mice led to a dose-dependent depletion of extrathymic T cells from the intraepithelial and lamina propria compartments of the small and large intestine. TCRαβ and TCRγδ, CD4⁺ and CD8α⁺ T cell subsets were affected. The depletion of intraepithelial, extrathymic T cells by oestradiol treatment was striking. Oestrogen, therefore, has an effect not only on genital mucous membranes, but also on the large, diffuse lymphoid tissues of the gut, in that it selectively depletes the intestinal, extrathymic T-cell subsets.     

Cellular damage and prevention in childhood hydrocephalus

The literature concerning brain damage due to hydrocephalus, especially in children and animal models, is reviewed. The following conclusions are reached:

• 1. 

  Hydrocephalus has a deleterious effect on brain that is dependent on magnitude and duration of ventriculomegaly and modified by the age of onset.