Targeting the leukemic stem cell: the Holy Grail of leukemia therapy

Since the discovery of leukemic stem cells (LSCs) over a decade ago, many of their critical biological properties have been elucidated, including their distinct replicative properties, cell surface phenotypes, their increased resistance to chemotherapeutic drugs and the involvement of growth-promoting chromosomal translocations. Of particular importance is their ability to transfer malignancy to non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice. Furthermore, numerous studies demonstrate that acute myeloid leukemia arises from mutations at the level of stem cell, and chronic myeloid leukemia is also a stem cell disease. In this review, we will evaluate the main characteristics of LSCs elucidated in several well-documented leukemias. In addition, we will discuss points of therapeutic intervention. Promising therapeutic approaches include the targeting of key signal transduction pathways (for example, PI3K, Rac and Wnt) with small-molecule inhibitors and specific cell surface molecules (for example, CD33, CD44 and CD123), with effective cytotoxic antibodies. Also, statins, which are already widely therapeutically used for a variety of diseases, show potential in targeting LSCs. In addition, drugs that inhibit ATP-binding cassette transporter proteins are being extensively studied, as they are important in drug resistance-a frequent characteristic of LSCs. Although the specific targeting of LSCs is a relatively new field, it is a highly promising battleground that may reveal the Holy Grail of cancer therapy.

Impaired p53 function leads to centrosome amplification, acquired ERalpha phenotypic heterogeneity and distant metastases in breast cancer MCF-7 xenografts

In this study, we establish an MCF-7 xenograft model that mimics the progression of human breast carcinomas typified by loss of p53 integrity, development of centrosome amplification, acquired estrogen receptor (ERalpha) heterogeneity, overexpression of Mdm2 and metastatic spread from the primary tumor to distant organs. MCF-7 cells with abrogated p53 function (vMCF-7(Dnp53)) maintained nuclear ERalpha expression and normal centrosome characteristics in vitro. However, following mitogen stimulation, they developed centrosome amplification and a higher frequency of aberrant mitotic spindles. Centrosome amplification was dependent on cdk2/cyclin activity since treatment with the small molecule inhibitor SU9516 suppressed centriole reduplication. In contrast to the parental MCF-7 cells, when introduced into nude mice as xenografts, tumors derived from the vMCF-7(DNp53) cell line developed a strikingly altered phenotype characterized by increased tumor growth, higher tumor histopathology grade, centrosome amplification, loss of nuclear ERalpha expression, increased expression of Mdm-2 oncoprotein and resistance to the antiestrogen tamoxifen. Importantly, while MCF-7 xenografts did not develop distant metastases, primary tumors derived from vMCF-7(DNp53) cells gave rise to lung metastases. Taken together, these observations indicate that abrogation of p53 function and consequent deregulation of the G1/S cell cycle transition leads to centrosome amplification responsible for breast cancer progression.

[Airborne contact dermatitis]

A comprehensive bibliographical retrieval of case reports on "airborne contact dermatitis" (ACD) was performed. The present review deals with the first cases published in 1986, 1991, 2001 by Huygens as well as by Dooms-Goossens, and continues with the other pertaining clinical presentations until to day. Solid particles, rather than gases or droplets, are the most frequently reported causes of ACD.

Analysis of G(-174)C IL-6 polymorphism and plasma concentrations of inflammatory markers in patients with type 2 diabetes and peripheral arterial disease

AIMS

To determine whether the G(-174)C interleukin 6 (IL-6) polymorphism influences the development of peripheral arterial disease (PAD) in individuals with type 2 diabetes. This was investigated by comparing the distribution of G(-174)C genotypes between patients with type 2 diabetes and PAD (PAD+) and those with type 2 diabetes but without PAD (PAD-). Plasma concentrations of IL-6, fibrinogen, C reactive protein (CRP), and vascular endothelial growth factor (VEGF) were also compared in PAD+ and PAD- patients.

METHODS

Blood samples were collected from 146 PAD+ and 144 PAD- patients. SfaNI was used to determine the G(-174)C genotype. Plasma concentrations of IL-6, fibrinogen, CRP, and VEGF were measured by an enzyme linked immunosorbent assay.

RESULTS

The GG genotype was more common in PAD+ patients than in PAD- patients. PAD+ patients also had increased mean plasma concentrations of IL-6, fibrinogen, CRP, and VEGF compared with PAD- patients. Mean plasma concentrations of IL-6, fibrinogen, and CRP in both PAD+ and PAD- patients were higher in those with the GG genotype than in those with the GC or CC genotypes. In contrast, mean plasma concentrations of VEGF in PAD+ and PAD- patients were not significantly different between those with different G(-174)C genotypes.

CONCLUSIONS

These results support a model in which the GG genotype promotes PAD development among individuals with type 2 diabetes by inducing increased release of IL-6. Higher concentrations of IL-6 among those with the GG genotype is associated with increased plasma concentrations of fibrinogen and CRP.

Frequency of bcl-2/IgH translocation in patients with non-Hodgkin's lymphoma and chronic hepatitis C virus infection

AIM

It has been previously suggested that t(14;18) translocation of bcl-2 to the immuno-globulin heavy chain (IgH) locus may contribute to pathogenesis of lymphoproliferative disorders related to hepatitis C virus (HCV) infection, including type II mixed cryoglobulinemia (MC).

METHODS

In this study, the presence or absence of t(14;18) translocation was determined in tumor biopsy specimens and peripheral blood mononuclear cells (PBMCs) for 48 NHL patients with chronic HCV infection.

RESULTS

In tumor biopsy specimens from 32 HCV-positive NHL patients, bcl-2/IgH translocation was detected in 1 of 13 patients with MC syndrome (7.7%) and 3 of 19 patients without MC syndrome (15.8%). In PBMCs from 23 HCV-positive NHL patients, this translocation was observed in 3 of 6 patients with MC syndrome (50%) and 4 of 17 patients without MC syndrome (23.5%). Interestingly, bcl-2/IgH translocation was found in 2 extranodal marginal zone B-cell lymphoma tissues from HCV-infected patients.

CONCLUSIONS

However, additional studies are required to better clarify the relationship between this translocation and extranodal marginal zone B-cell lymphoma development. Although the frequency of bcl-2/IgH translocation in PBMCs from patients with chronic HCV infection is higher than that of other NHL patients, this increased translocation rate remains to be elucidated.

GFP-centrin as a marker for centriole dynamics in the human breast cancer cell line MCF-7

Centrosome duplication plays an important role in genomic stability through bipolar spindle formation and equal chromosome segregation during mitosis. Defects in centrosome duplication and centrosome amplification correlate with aggressive tumors and aneuploidy. Cyclin-dependent cell cycle regulators play a key role in signaling centrosome duplication and the tumor suppressor genes p53, BRCA1 and BRCA2 are suspected to function at mitotic checkpoints that monitor centrosome duplication. The relationship between loss of hormone dependence in breast cancer, and signaling of centrosome duplication in tumor progression is not known. We have developed a MCF-7 cell line expressing GFP-centrin that allows direct visualization of centriole duplication during the cell cycle in living cells. GFP-centrin is expressed and selectively incorporated into the structure of both centrioles making them clearly visible in living cells. Our studies demonstrate three important aspects of recombinant GFP-centrin incorporation into centrioles. 1) GFP-centrin transfected cells grow normally in culture and show no adverse effect associated with GFP-centrin expression; 2) newly duplicated centrioles incorporate centrin during their genesis; and 3) GFP-centrin incorporation into centrioles does not grossly affect cell cycle progression, or centrosome function.

Effect of 17-beta estradiol and epidermal growth factor on DNA and RNA labeling in astroglial cells during development, maturation and differentiation in culture

Growth factors stimulate astroglial and neuronal proliferation and differentiation in culture. Estrogens markedly influence astroglia, and are key factors participating in neurodegeneration. The aim of the present study was to investigate interactions between estradiol (E2) and epidermal growth factor (EGF) during astroglia development, maturation and differentiation in culture. DNA or RNA labeling in 16 or 40 or 60 days in vitro (DIV) astrocyte cultures treated for 24 or 48 h with EGF and/or E2 was evaluated. A significant increase in DNA labeling in 16 DIV astrocyte cultures treated for 24 h with EGF (5 ng/ml) and E2 (1 nM) was found. EGF (5 or 10 ng/ml) addition in the last 24 h in 48 h E2 (1 or 5 nM)-treated astrocyte cultures at 16 DIV caused a slight, but significant increase in DNA labeling. No differences in RNA labeling were observed in 16 DIV astrocyte cultures treated for 24 or 48 h with EGF (5 or 10 ng/ml) in the presence of E(2) (1 or 5 nM). A significant stimulation in DNA labeling was shown in 40 DIV astrocyte cultures treated for 48 h with E2 (1 or 5 nM) in the presence of EGF (5 or 10 ng/ml) added in the last 24 h. In well differentiated astroglial cell cultures (60 DIV), DNA labeling was remarkably increased after 24 h treatment with 1 nM E2 or 5 ng/ml EGF. Co-addition of 1 nM E2 and 5 ng/ml EGF for 24 h reduced [methyl-(3)H]thymidine incorporation, when data are compared to E2- or EGF-treated cultures. Addition of EGF in the presence of E2 for 48 h or only in the last 24 h caused a significant decrease of [methyl-(3)H]thymidine incorporation in comparison with EGF-treated cultures at 60 DIV or with untreated cultures. Treatment of cultures for 24 h with EGF (5 or 10 ng/ml) alone or in combination with E2 (1 or 5 nM) induced a strong increase of RNA labeling in 60 DIV astrocyte cultures. Addition for 48 h of E2 (1 or 5 nM) or EGF (5 or 10 ng/ml) alone or in association stimulated significantly RNA labeling in astrocyte cultures at 60 DIV. When 60 DIV astrocyte cultures were treated for 48 h with E2 (1 or 5 nM) in the presence of EGF (5 or 10 ng/ml) added only in the last 24 h, a potentiating effect of RNA labeling was observed. The above results suggest that interaction between growth factors and estrogens may contribute to regulate astroglia development, maturation and differentiation.

Rapid screening of the LDL receptor point mutation FH-Genoa/Palermo. Mutation in brief no. 238. Online

The LDL-receptor gene point mutation FH-Genoa/Palermo is the most frequent mutation responsible for Familial Hypercholesterolemia in Sicily. The mutation does not introduce or abolish any useful restriction site. We establish a GeneComb-based strategy to identify this mutation in a population of Sicilian unrelated clinically diagnosed FH probands. The method was very sensitive and specific; 12 out of 90 (13.3%) unrelated FH probands were found to carry the FH-Genoa/Palermo mutation. According to these results, the FH-Genoa/Palermo is the more frequent LDL-receptor gene mutation among the Sicilian FH patients. Moreover FH-Genoa/Palermo is the mutation cluster to date more represented in Southern Italy.

Immunolocalization of CD44 adhesion molecules in human periradicular lesions

OBJECTIVE

The hyaluronate receptor CD44 is a cell surface protein that is involved in several functions. To elucidate whether CD44 plays a role in periapical lesions, an immunohistochemical technique was used to study its distribution.

STUDY DESIGN

Twenty periapical lesions-16 periapical granulomas and 4 radicular cysts-constituted the sample. Formalin-fixed/paraffin-embedded tissue sections were studied by means of immunohistochemistry for the presence of the standard CD44H form and its V3 splicing variant.

RESULTS

Immunohistochemical staining for CD44H and CD44V3 was observed on epithelial, endothelial, and connective tissue cells. The cells of the fibrous lining around each granuloma were positive, showing an immune reactive pattern directly correlated with the dimension of the lesion. Epithelial rests of Malassez were strongly positive; the reaction product was also evident in the epithelial lining of the cysts. Blood vessels, mainly observed around the lesion, were immunoreactive for CD44.

CONCLUSIONS

Our findings demonstrate that CD44H and its V3 variant are expressed in at least 3 different tissue types of periapical lesions. These glycoproteins may be involved in different steps of periapical lesion pathogenesis and evolution.

Alteration in alpha 2 integrin immunocytochemical expression on cultured human gingival fibroblasts following nicotine exposure

BACKGROUND

Clinical epidemiologic studies carried out in smokers versus non smokers support the concept that tobacco-related factor may affect the periodontal tissues and wound healing.

METHODS

In this study, the role of nicotine on the integrin alpha 2 chain immunocytochemical expression, in human gingival fibroblasts (HGF) was investigated in vitro. The kinetic induction of this type of integrin on HGF in response to increasing percentage of nicotine was been characterized. A human gingival fibroblast strain, derived from a healthy individual with non-inflamed gingiva, was used in this study. The cells were then grown on acetylated microscope slides and fixed with cold ethanol, samples were then incubated for 16 to 19 hrs at 4 degrees C to anti-human alpha 2 integrin chain monoclonal antibody.

RESULTS

In control cultures and in HGF treated with 0.025 microM nicotine the initial higher expression of alpha 2 chain decreased (grade 1 in both culture) while in HGF treated with 0.075 microM increased (grade 3). After 48 hours HGF exposed to 0.075 microM nicotine, increased further their expression of alpha 2 chain.

CONCLUSIONS

The results obtained demonstrate a dose-time dependent nicotine influence on immunocytochemical expression of alpha 2 integrin chain. These data suggest that nicotine may promote a collagene breakdown via an increase of alpha 2 integrin chain expression.

Blood levels of transforming growth factor-beta 1 (TGF-beta1) are elevated in both relapsing remitting and chronic progressive multiple sclerosis (MS) patients and are further augmented by treatment with interferon-beta 1b (IFN-beta1b)

The serum levels of TGF-beta1, measured by solid-phase ELISA, were determined to be significantly augmented in patients with both relapsing remitting (RR) and secondary chronic progressive (CP) MS compared with sex- and age-matched healthy controls. Moreover, in RR MS patients, the blood levels of the cytokine were further augmented either during relapses or, in a rapid but reversible fashion, by s.c. injection with 8 million International Units (MIU) IFN-beta1b. Because TGF-beta1 possesses multiple anti-inflammatory activities, we hypothesize that the increase in its circulating levels in RR and CP MS patients might represent an endogenous anti-inflammatory mechanism aimed at counteracting ongoing immunoinflammatory events, and that IFN-beta may further potentiate this natural defensive apparatus.

Expression of alpha6 and beta4 integrin subunits on human endometrium throughout the menstrual cycle and during early pregnancy

OBJECTIVE

To evaluate the expression of alpha6 and beta4 integrin subunits on surface and glandular endometrium throughout the menstrual cycle and during early pregnancy.

SETTING

Second Department of Obstetrics and Gynecology, University of Catania, Catania, Italy.

PATIENT(S)

Thirty-two women. Nineteen of the women regularly menstruated in different phases of the cycle, and 13 were in the sixth to ninth week of gestation and required voluntary abortion.

INTERVENTION(S)

Endometrial specimens collected during endometrial biopsy, hysterectomy, or voluntary abortion.

MAIN OUTCOME MEASURE(S)

Immunohistochemical staining for alpha6 and beta4 integrin subunits in endometrial tissues.

RESULT(S)

Both subunits (poorly expressed in preimplantation days) reached a significant peak on the endometrial surface during the implantation window, which tended to disappear in the postimplantation phase. On glandular endometrium they exhibited an opposite trend, showing high levels in the preimplantation and postimplantation days, whereas their expression decreased during the implantation window. The two subunits tended to disappear in early pregnancy.

CONCLUSION(S)

alpha6 and beta4 integrin subunits are uniformly distributed and highly expressed on the endometrial surface during the implantation window; they decreased dramatically in the postimplantation phase. These results could suggest involvement of integrin-extracellular matrix components in blastocyst-endometrium interaction during the early stages of implantation.

Paradoxical antidiabetogenic effect of gamma-interferon in DP-BB rats

Previous studies have shown that anti-gamma-interferon (IFN-gamma) antibody reduces the frequency of autoimmune IDDM in the DP-BB rat. We tested the effects of systemically administered recombinant rat IFN-gamma in both DP-BB and DR-BB rats. Unexpectedly, IFN-gamma markedly reduced the incidence of IDDM as compared with control rats when administered six times per week at a dosage of 280,000 U between ages 30-35 to 105 days or ages 60-64 to 105 days. A lower dosage (28,000 U on alternate days) was also protective when administered to DP-BB rats between birth and age 60 days. However, long-lasting protection against IDDM development over the 1-year study period was achieved only by the highest dosage of IFN-gamma administered from age 30 to 105 days. Ex vivo production of tumor necrosis factor-alpha from splenic lymphoid cells (SLCs) and peritoneal macrophages of the rats treated with IFN-gamma was comparable with that of controls; however, SLCs from the IFN-gamma-treated animals secreted lower amounts of IFN-gamma after stimulation with concanavalin A. IFN-gamma treatment also markedly reduced the frequency of phenotypically activated SLC-expressing class II antigens and interleukin-2 receptor. Finally, in agreement with the observed antidiabetogenic effects, exogenously administered IFN-gamma induced neither insulitis nor IDDM development in DR-BB rats, a subline of DP-BB rats in which autoimmune diabetes rarely occurs spontaneously but can be induced by administration of polyinosinic-polycytidilic acid.

Pituitary adenylate cyclase activating polypeptide prevents apoptosis in cultured cerebellar granule neurons

The two forms of pituitary adenylate cyclase-activating polypeptide, PACAP27 and PACAP38, are two neuropeptide hormones related to the vasoactive intestinal peptide/secretin/ glucagon family of peptides. PACAP receptors that are positively coupled to adenylyl cyclase and phospholipase C have been identified in cultured cerebellar granule cells. Using the reverse transcription-polymerase chain reaction methodology, we demonstrated the expression of the PACAP-R and PACAP-R-hop mRNAs in cultured granule cells. When grown in the absence of serum or in low K+ concentrations, these neurons underwent apoptosis, a naturally occurring process characterized by cell shrinkage and internucleosomal DNA cleavage. We used these models of programmed cell death to study the relationship between PACAP receptor activation and neuronal apoptosis. Treatment with PACAP27 and PACAP38 reduced the development of apoptosis in a dose-dependent manner. The neuroprotective activity of PACAP was mimicked by high concentrations of vasoactive intestinal peptide or forskolin but not by carbamylcholine. Thus, we suggest that the activation of type I PACAP receptors may contribute to the survival of cerebellar granule neurons.

Tissue-specific and developmental expression of pituitary adenylate cyclase-activating polypeptide (PACAP) receptors in rat brain

The two forms of pituitary adenylate cyclase-activating polypeptide, PACAP27,and PACAP38, are novel members of the vasoactive intestinal peptide (VIP)/secretin/glucagon family of peptides. PACAP receptors that are positively coupled to adenylate cyclase and phospholipase C have been recently identified. We examined the expression of PACAP receptors in the rat cortex, hippocampus, cerebellum and hypothalamus during postnatal development. Functional studies revealed PACAP stimulation of cAMP formation in all the brain areas examined and [3H]inositol monophosphate ([3H]InsP) accumulation only in the cerebellum and hypothalamus. Throughout development, the efficacy or PACAP in stimulating cAMP formation slightly increased in the cortex and hypothalamus and decreased in the hippocampus and cerebellum; PACAP stimulation of [3H]InsP formation decreased in the cerebellum and remained steady in the hypothalamus. The effects of PACAP27 and PACAP38 on cAMP levels and inositol phospholipid hydrolysis were dose-dependent between 1 and 100 nM. In the same brain areas, treatment with VIP increased cAMP formation at doses greater than 100nM and failed to affect [3H]InsP content, thus suggesting the existence of type-1 PACAP receptors. The reverse transcription polymerase chain reaction (RT-PCR) was used to analyse the mRNA expression of type-1 PACAP receptor splice variants. PACAP receptor gene expression in the central nervous system was regulated in a developmental- and tissue-specific manner. The PACAP-R transcript was detected in all the brain areas examined whereas PACAP-R-hop mRNA ocurred only in the cerebellum and hypothalamus. The different expression profiles and functional properties of PACAP receptors in the developing rat brain suggest an involvement of PACAP in histogenesis, maturation and neurotransmission.

Differentiation induces pituitary adenylate cyclase-activating polypeptide receptor expression in PC-12 cells

The two forms of pituitary adenylate cyclase-activating polypeptide (PACAP), PACAP27 and PACAP38, are neuropeptide hormones related to the vasoactive intestinal peptide/secretin/glucagon family of peptides. PACAP receptors that are positively coupled to adenylyl cyclase and phospholipase C have been recently identified. We have investigated the expression of PACAP-Rs in undifferentiated and differentiated PC-12 cells. PACAP27 and PACAP38 failed to significantly increase cAMP or [3H]inositol monophosphate levels in undifferentiated PC-12 cells treated with vehicle, insulin-like growth factor I, or epidermal growth factor but greatly elevated levels after differentiation with nerve growth factor (NGF) or basic fibroblast growth factor. PACAP responsiveness increased significantly after 24 hr of NGF treatment, reaching a maximum within 4 days. At this time of differentiation, the effect of PACAP was dose dependent between 1 nM and 0.1 microM, whereas vasoactive intestinal peptide, at the maximal dose of 10 microM, slightly increased cAMP formation and failed to affect [3H]inositol monophosphate content. Radioreceptor assays, performed with 125I-PACAP27, revealed the induction of high affinity type I PACAP receptors in differentiated PC-12 cells. Using reverse transcription-polymerase chain reaction methodology, we showed the absence of type I PACAP receptor mRNAs in undifferentiated PC-12 cells and the expression of PACAP-R-hop mRNA after NGF or basic fibroblast growth factor treatment. The increased PACAP responsiveness induced by these growth factors in PC-12 cells may therefore result from the expression of the PACAP-R-hop isoform, positively coupled to both adenylyl cyclase and phospholipase C.

[A polymorphism study of the DNA extracted from dental tissues]

Often teeth are the only items which can be used for personal identification in forensic medicine. In the present work we describe a method to extract and amplify DNA from dental elements ranging from 2 weeks to 5 year from the avulsion. PCR (polymerase chain reaction) was used to amplify VNTR sequences; the alleles products were electrophoresed, visualized by traditional methods and compared to the amplified products obtained from the matching blood sample. Our results give a new and powerful investigative tool for personal identification in the field of forensic odontostomatology, since such a procedure can be successfully applied both to recent and to ancient teeth.

[Immunologic study on patients with head and neck cancer treated with thymopentin associated with surgery, chemotherapy and radiotherapy]

Patients with H&N tumours treated with surgery, chemo- and radiotherapy also underwent an immunologic therapy with timopentina to evaluate clinic and immunologic efficacy during a 1-year follow-up. Twenty-five patients were recorded in this study divided at random into two groups. In group A the patients were administered timopentina (50 mg/3 times per week/6 weeks) subcutaneously in 4 o 5 cycles during the year. Group B were not administered timopentina. The immunologic state was assessed through investigation of the following: Evaluation of PBL and their T and B cell subpopulations Phagocytosis and blastigenesis Surface receptor and soluble receptor of IL2 NK activity IL1 production. The immunologic values of the two groups were correlated against a control group of twenty non-neoplastic patients. Our study revealed a better immunologic conditions at the end of follow-up in patients treated with timopentina compared to the other patients.

Expression of ornithine decarboxylase gene in elderly human monocytes

The proliferative capacity of the immune system is impaired in elderly subjects and the expression of various genes involved in cell cycle progression is reduced in PHA stimulated lymphocytes during the aging process. Macrophages play a fundamental role in the immune system response. It has recently been demonstrated that the process of macrophage activation is accompanied by a rapid, transient rise of ornithine decarboxylase (ODC) mRNA levels. In fact, the ODC gene seems to be involved in macrophage activation and differentiation. The authors demonstrated that the steady-state levels of ODC mRNA and the correlated superoxide anion production are lower in the monocytes of elderly subjects with respect to those in young subjects used as control. These results confirmed the impaired immune function of the elderly.

A simplified method of pig islet isolation

This study reports a simplified, low-cost, easily performed chemico-mechanical isolation method of the islets of Langerhans. The experimental study was carried out on 15 adult pigs. Our method used collagenase and a digestion chamber for islet isolation and yielded 2,240 +/- 613 islets per g treated pancreas after purification. This demonstrates that the method is reliable and can give satisfactory results.

[Different behavior of phagocytes in young and old subjects]

Ageing is a dynamic phenomenon in which there is a physiological decay in all the functions of the individual. The consequence is an increased susceptibility to infections, autoimmune diseases and cancer. Phagocytic cells as polymorphonuclear leukocytes (PMNL) and monocytes (Mo) are of prime importance in the defence against invasive agents, PMNL and Mo seek out and destroy invading micro-organisms. Chemotaxis and phagocytosis are two mechanisms that are activated by these cells for this purpose. In this study, using "in vitro" techniques, we have verified if, at the level of such functions of cell defense, there could be variations in elderly subjects with respect to younger subjects. Our results show a chemotactic activity of PMNL in the elderly that is higher and a phagocytic activity that is lower. As regards Mo, there is a lower chemotactic activity in the elderly and only a slight difference in phagocytic activity with respect to the younger subjects. These results are in agreement with those found at the clinical level showing the elderly less protected from infection with respect to younger subjects.

Expression of cell cycle-dependent genes and proliferative state of lymphocytes in aging

The authors analyzed the expression of some genes involved in the control of T lymphocyte proliferation in a group of healthy elderly subjects. They focused their attention on genes involved in the G(0)/G(1) transition (TK, PCNA, H3, IL2-R) and showed decreased expression in the TK, H3 and IL2-R genes. Using flow cytofluorimetry, delayed transition from the G(0)/G(1) to the S stage was observed.

[Immunogenic activity of a polyvalent oral vaccine]

The AA. studied the effects of a polyvalent oral vaccine on the cellular immunity, and on IgA level in animal. They also studied its ability to reactivate the response to the Clostridium tetani toxin in human volunteers. The results show a very good ability of the vaccine as specific and aspecific stimulator.

[Protection of an oral vaccine against experimental infection of mice and its role combined with the administration of penicillin]

The AA. studied the immunologic profile of an oral vaccine to prevent the experimental infection in mice and its effect when it was administered with antibiotic. The mice were infected with Staphylococcus aureus and protected by the vaccine administration. Our results confirmed the higher survival in the group that used this combination. The observed mortality was lower in group of mice treated with vaccine and penicillin combination, than in the untreated group.

Pathophysiology of the immune system in elderly subjects with or without diabetes and variations after recombinant interleukin-2

This study reports two groups of elderly diabetic patients and normal subjects, with or without hypercholesterolemia and hypertriglyceridemia, who presented a decrease of the T lymphocyte-mediated function, proliferative capacity, phagocytosis, cytotoxicity and surface markers. This fall was more evident in hypercholesterolemic and hypertriglyceridemic subjects. The humoral responses and other parameters studied did not reveal significant variations. The authors also observed that recombinant interleukin-2 (rIL-2) stimulation determined a satisfactory response in healthy and diabetic subjects, while it did not normalize values in patients with altered lipid balance.

[Immunologic characteristics of a polyvalent vaccine]

A lot of bacterial vaccines show a very interesting immunostimulating profile. The AA. studied the effects of a polyvalent vaccine on the phagocytosis, on the cellular immunity and on the IgA production. They also investigated its capacity to reactivate the response to the C tetani toxin (Booster effect), both "in vitro" and in human volunteers. The results show a significant improvement in the immunity response to specific and aspecific stimuli.

Complement and its fractions (C3-C4) pattern in subjects with neoplasia

The total complement (CH50) and its fractions C3 and C4 have been assayed for up to two years after surgery in subjects with breast, gastric and colon-rectum carcinomas. In all three types of pathology a constant pattern has been observed. Before surgery the CH50 stayed below the normal range but was increased following surgery. After a month it was again within the normal range and subsequently, according to the clinical evolution of the disease, it remained normal in those patients without relapse or any apparent metastasis, whereas in those patients who displayed metastasis and/or approached the terminal phase it fell below the normal range. The C3 fraction followed the CH50 pattern whereas the C4 did not show any variation correlated with the stages of the disease.

Effect of immunization against human chorionic gonadotropin (hCG) on transplantation of Yoshida ascitic tumour

The human chorionic gonadotropin (hCG) is considered a marker of DNA derepression on neoplastic cells. The human chorionic gonadotropin antibodies (anti-hCG antibody) inhibit the growth of yoshida tumour cells in preimmunized recipient rats. A close relationship between the anti-hCG antibodies and tumour cell transplantation has been observed. This relationship and further experimental implications are briefly discussed.

Effect of levamisole and methisoprinol on in vitro lymphocyte reactivity in chronically irradiated subjects and patients affected by neoplasias

The data of this experiment show that Levamisole moderately stimulates T-lymphocyte proliferation and efficiency in vitro and methisoprinol markedly does so when both drugs act in combination with PHA in subjects with severely impaired cell-mediated responsiveness, whereas they do not exert any effect on lymphocytes in normal subjects. B-lymphocyte in vitro responsiveness does not appear to be affected by the immunomodulators, except for some cases of cancer of the stomach wherein B-lymphocyte responsiveness is stimulated in vitro by Levamisole and more evidently by Methisoprinol. These data support the use of Methisoprinol or Levamisole in therapy, and further investigations regarding the mechanisms whereby they might act and the dose-effect relationship which might show to be important for the type of desired immunomodulation would appear appropriate.

[Action of levamisole on lymphocytic reactivity in naso-laryngeal carcinoma]

It was confirmed that the mitogenic reactivity and rosette-forming cells capacity of T and B lymphocytes were depressed in nose-pharyngeal tumor bearing patients. Using levamisole treatment, the response of T cells was increased till almost the normal value. B cells response was normal or slightly increased after levamisole treatment. Our experiments suggests that the levamisole is capable to induce an increased response of the immune system when compared to untreated tumor bearing patients.

[Immunological monitoring of patients with carcinoma of the lung. Study method and preliminary research]

It is by now an established fact that the status of the immune system stands in some relationship with the onset and evolution of malignancy. To clarify this relationship the authors investigated the immune system of patients with pulmonary carcinoma, with special regard to the functions of the T and B lymphocyte lines. After suitable explanation of their experimental protocol, which involved immunological monitoring and the study of relationships between immunological changes and the extent and histological type of malignancy, and also the effects of any treatments being administered, the authors describe the results obtained in 18 preoperative patients. The study revealed an overall diminution of cell-mediated immune activity: less strongly positive DNCB skin tests, reduced capacity for making E rosettes, reduced blast transformation with PHA. With B lymphocytes the EA rosette test was often depressed, whereas antibody titers were normal or even above normal, and the pokeweed blast test was invariable above normal values. These preliminary results show that at the time of diagnosing malignancy, the greater aggressiveness characteristic of the less differentiated cellular types, or of stages of diffuse malignancy, is associated with overpowering of cell defenses and (within certain limits) enhancement of the humoral response.

Immuno-deficiency in Schwartz-Jampel syndrome

Two sisters born in a consanguineous marriage and affected by Schwartz-Jampel syndrome had a complex immunodeficiency, involving not only the humoral but also the cellular immune response.

[Effects of lymphocyte stimulation in vitro of alkaline salts of some aroyl-hydrazino-carbodithioic acids and 1,3,4-oxadiazole derivatives: preliminary research]

The behaviour of alkaline salts of some aroyl-hydrazine-carbodithioic acids [comp. Ia,b,c,] and derivatives of 1,3,4-oxadiazole [comp. IIa,b,c, e IIIa,b,c] , has been studied, on the capability of lymphoblasts in vitro, in consequence of stimulation by some mitogen agents (PHA, PWM). It has been pointed out that the considered compounds inhibit the cellular mitosis in variable percentage in relation to their structure and to the used mitogen agent, frequently causing some mitogen-like morphological modification, also revealable under a optical microscope. The higher inhibition has been obtained by the Ic, IIc, and IIIc compounds, in which Ar is the 3,4-dihydroxymethylenephenyl radical, proving selective, in some cases, for the T lymphocytes.

[Changes in the membrane receptors of lymphocyte populations during immunization]

A population of splenic lymphocytes has been studied as well as their surface antibodies and their affinity for antigen in different days and periods of immunization. Fractionation of a specific population of lymphocytes having an affinity for antigens coated on glass beads were accomplished. The other aspecific population did not bind ot the glass beads and was not retained on the column. During the primary immuno-response the number of lymphocytic cells with surface antibodies specific for antigen was higher than in the booster response: in secondary response only the total number of antibody forming-cells increases while the number of lymphocytes with surface antibodies is constant. The authors suppose that the surface of spleen lymphocytes is modificated in different way at different time, by immunizing antigen.