Assessment of neutrophil apoptosis ex vivo in hepatosplenic patients with neutropenia pre and post splenectomy.

UNLABELLED: The pathophysiology of neutropenia seen in patients with schistosomiasis or hepatitis C infection that complicates the course of liver disease is poorly understood. We evaluated the neutrophil apoptosis before and after splenectomy to clarify the role of apoptosis and splenomegaly in the occurrence of neutropenia. Neutrophils were isolated from 23 hepato-splenic patients with neutropenia, 8 hepatosplenic patients with normal neutrophil counts, 7 patients who were post splenectomy, and a further ten normal control subjects. These were cultured for 24 h and the time course of neutrophil apoptosis was assessed by determination of Annexin V and propidium iodide binding by flow cytometry. Fas and Bcl2 expression were determined on fresh neutrophils using flow cytometry. Levels of tumor necrosis factor alpha, interleukin 3, and gamma interferon were evaluated using an immunosorbent assay. Neutrophil apoptosis was minimal in the fresh neutrophils, however, cultured neutrophils exhibited significantly greater apoptosis in neutropenic patients when compared to non-neutropenic patients (P=0.01 at 4 h and P<0.05 at 24 h) and control group (P<0.01 at 4 h and 24 h). After splenectomy, the percentage of neutrophil apoptosis declined to the normal control levels (P>0.05). Fas and Bcl2 expression on neutrophil were significantly higher in the neutropenic group as compared to normal controls (P<0.05, P=0.01 respectively). Serum TNF alpha, IL-3, and IFN gamma levels were not significantly different in all studied groups. IN CONCLUSION: Neutrophils from neutropenic hepatosplenic patients exhibit markedly accelerated apoptosis, which is normalized after splenectomy. Thus increased neutrophil apoptosis may in part be responsible for the occurrence of neutropenia.

The Relevance of Circulating Interleukin-5 (IL-5) in Lymphoproliferative Disorders.

It is well substantiated that several cytokines have a regulatory action on the neoplastic process of different lymphoproliferative disorders (LPDs). The objective of this study was to clarify the role of interleukin-5 (IL-5) as a factor in disease phenotype and progression and as a mediator of eosinophilia in patients with LPDs. We have therefore measured the concentrations of IL-5 in sera of 49 untreated patients with different LPDs with mean (SD) age of 34.2 (21.2) years and M/F ratio of 29/20. Patients were subdivided according to the category of LPD into: Group 1 (NHL; n = 36), Group 2 (CLL; n = 5) and Group 3 (HD; n = 8). In addition, 14 matched controls were studied in parallel. The major differences among the three categories of LPDs were elicited in parameters reflecting the lymphocytic tumor burden; i.e. peripheral blood (F= 73.785; p =.000) and bone marrow (F = 55.662; p =.000) lymphocytic counts. Serum IL-5 level came next in statistical significance to lymphocytic parameters (F = 10.291; p =.000) with the highest levels being encountered in CLL patients. In NHL group, a concomitant rise of serum IL-5 levels accompanied the increasing grade of lymphoma (X(2) = 13.11; p =.004). Furthermore, IL-5 concentration was well correlated with different features known to be characteristic of LPDs; particularly and in a descending order: absolute eosinophilia (r =.599; p =.000), absolute lymphocytosis (r=.498; p =.000), bone marrow lymphocytosis (r =.436; p =.002) and bone marrow infiltration (r =.375; p =.008). The data are in favorof the fact that IL-5 is crucial in the generation of neoplastic phenotype and may also be responsible for some paraneoplastic features seen in LPDs.

Intestinal spore-forming protozoa among patients suffering from chronic renal failure.

Cryptosporidium parvum, Isospora belli, Cyclospora cayetanensis and Microsporidia are four intestinal spore-forming protozoa that cause diarrhoea in immuno-competent individuals and immuno-suppressed patients. Fresh stool samples were obtained from 120 patients suffering from CRF and attending the Dialysis Unit of Zagazig University Hospital. Also, stool samples were obtained from 40 immuno-competent individuals complaining of diarrhoea (control group). The stool samples were examined by direct smear and formol-ether concentration methods then stained by Giemsa, Modified Ziehl Neelsen (MZN) and Aniline carbol methyl violet stains. The four intestinal spore-forming protozoa were detected in 40/120 (33.3%) of patients with CRF and in 2/40 (5.0%) of the control group with a statistically highly significant difference (P < 0.001). C. parvum, Microsporidia, C. cayetanensis and I. belli were detected in 18/120 (15%), 10/120 (8.3%), 9/120 (7.5%) and 3/120 (2.5%), respectively. The four protozoa were found as mixed infections with other pathogens or as single infections confirming their role alone as a cause of diarrhoea. MZN stain was the most efficient simple, and not expensive.

Value of estimating intraocular antibody production in diagnosis of typical and atypical lesions of ocular toxoplasmosis.

Serum and aqueous humor (AH) samples were collected from 45 patients: 20 with typically active or reactivated retinal lesions of Toxoplasma (Group I), 16 with atypical lesions (Group II) and 9 with old quiescent scars (Group III). Also, serum and AH samples were collected from 10 patients with chronic toxoplasmosis without any ocular manifestation (Group IV). T. gondii specific IgG, IgA and IgM antibodies were measured by ELISA in AH and serum and the intraocular (local) antibody production was determined by calculating Goldman-Witmer coefficient (G.W.C.). IgG antibodies were the only class detected in all sera of patients with ocular and nonocular toxoplasmosis. An intraocular IgG antibody synthesis was confirmed in 95% and 37.5% of patients with typical (Group I) and atypical (Group II) posterior uveitis respectively and in none of either patients with quiescent scars (Group III) or the ophthalmologically free patients (Group IV). As regard the typical active lesions, the sensitivity of the IgG assay (95%) was higher than that of IgA (60%) and IgM (5%) assays. Beside the conclusion that AH analysis to detect local antibody production is more reliable than the estimating of serum antibodies for the diagnosis of ocular toxoplasmosis, the detection of AH specific antibodies in 6 atypical cases, who were treated successfully by antitoxoplasmic therapy, represent a help to increase the number of uveitis cases in which specific treatment can be established.

Evaluation of the role of Ancylostoma caninum in humans as a cause of acute and recurrent abdominal pain.

Ancylostoma caninum is responsible for cases with eosinophilic enteritis (EE) and unexplained abdominal pain with peripheral eosinophilia in man. Ninety-five patients with obscure acute or recurrent abdominal pain and ten asymptomatic healthy parasite free were subjected to thorough history taking, clinical examination, sonography, routine laboratory investigations and serotesting by IgG ELISA to detect antibodies to excretory/secretory (ES) antigens of adult A. caninum and by IgG and IgG4 Western blot (W.B.) to detect antibodies to Ac68 antigen. Eleven male patients (11.6%) (5 with acute abdomen, 3 diagnosed as appendicitis and 3 had recurrent mild to moderate abdominal pain) fulfilled the criteria of case definition of human enteric infection with A. caninum (G.I). The study also detected human hookworm infection in 14 patients (G.IIb) other parasites in 34 patients (GIIc) and 36 patients had no parasites (G.IIa). Although 3 patients from group I were diagnosed as appendicitis and were dealt with surgically, the pain recurred and mebendazole only put an end to the patient's complaints. The obtained appendices of these operated cases showed marked eosinophilic infiltration but no adult canine hookworms were detected. IgG ELISA was positive in 72.7%, 8.3%, 100%, 23.5% and 0% in groups and control respectively. IgG and IgG4 W.B. did not increase the sensitivity but IgG4 W.B. elevated specificity to 100% excluding those with HH infection (Group Iib) who showed 100% cross-reactions. Stool analysis was the only differentiation between these two types of hookworms. These findings confirmed the presence of human enteric infection with A. caninum as clinical entity in the study community and referred to its value in differential diagnosis of the obscure abdominal pain.

Toxocariasis as a cause of renal disease in children in Sharkia Governorate, Egypt.

Eighty four children (40 males and 44 female) suffering from renal troubles were chosen as well as 20 healthy children as a control group. Urine and stool of patients were examined and chosen to be free from parasitic infections other than Toxocara. Each child was subjected to history taking, full clinical examination, urine analysis, kidney function tests and differential leucocytic count, examination of sera and urine by ELISA and microprecipitin tests for Toxocara antibodies. ELISA revealed 10.7% of patients to be seropositive for toxocariasis versus 5.3% in control group. This difference was statistically insignificant P > 0.05. In urine, ELISA revealed 2 positive cases out of the 84 patients, while it was negative in control group. These 2 cases were suffering from nephrotic syndrome. Microprecipitin test in sera was positive in 9.5% of patients and negative in control group. It was also negative in urine of patients and control group. Eosinophilia was found in 66.6% of seropositive patients. IgG antibodies to Toxocara were detected in males more than females between the age of 2-7 years, but insignificant (P > 0.05). It was also found in 77.7% of rural compared to 22.2% of urban areas. This difference was statistically significant (P < 0.05). It was concluded that toxocariasis should not be missed in the differential diagnosis of such renal diseases especially those who are not responds to the traditional management.

Serological diagnosis of extraintestinal Sarcocystosis.

The present study was carried out on eighty patients attending Zagazig University Hospitals. Forty cases suffered idiopathic cardiac diseases (28 with cardiomyopathy, 8 with myocarditis & 4 with valvular lesions) and forty cases suffered idiopathic rheumatic diseases (30 with musculoskeletal complaints and 10 with myositis). Sera were investigated by enzyme-linked immunosorbent assay (ELISA) and indirect fluorescent antibody technique (IFAT) using Sarcocystis fusiformis antigen in order to detect the role of Sarcocystis in initiation of these diseases. Twenty positive toxoplasmic sera and sera from twenty normal individuals were considered as control group. The sera of the investigated cases were tested against Toxoplasma gondii antigen to exclude it as one of the causative agents of these idiopathic lesions. No statistical difference was found between IFAT and ELISA in diagnosis of sarcocystosis (P < 0.05). Also, there was no cross reaction between Sarcocystis and Toxoplasma. This study showed that Sarcocystis can be considered as one of the possible causes of some idiopathic diseases.

Prevalence of Fasciola infection among school children in Sharkia Governorate, Egypt.

This study was performed on 1350 school children from 9 different villages in Sharkia Governorate to investigate the real situation of endemicity of fascioliasis in the area. Stool examination using modified Kato thick smear method was performed to detect Fasciola infection and other parasites. Those with negative stool samples were examined serologically by ELISA test to detect anti-Fasciola IgG. All cases with positive anti-Fasciola IgG were further examined by circum-oval precipitin test (COPT) against viable S. mansoni eggs to exclude the crossly reacted Schistosoma infections. Sixty nine cases were found to pass Fasciola eggs in their stool samples (5.1%). Anti-Fasciola IgG was detected in the sera of 231 children (17.1%) using ELISA test. Eighty four out of the 231 children were found positive by COPT and were considered as schistosomal cases. The remaining 147 who gave negative COPT were considered as Fasciola infections. All of the 69 Fasciola positive stool cases were found positive by ELISA test and negative by COPT test. The sensitivity of stool analysis was 47% versus 100% sensitivity of ELISA, whereas the specificity of ELISA was 63%. The total number of Fasciola positive cases by ELISA and stool analysis were 147 cases among 1350 children indicating a prevalence of 10.9% among school children in Sharkia Governorate. This results highlighting the importance of health education and snail control in decreasing the high prevalence.

Tumor necrosis factor and human acute leukemia.

Tumor necrosis factor (TNF) is a major regulator of AML growth in vitro and markedly enhances AML growth induced by GM-CSF/IL-3. TNF, on the other hand, suppresses the G-CSF stimulated AML cell proliferation and serves as a modulator of growth factor receptors on AML cells. It upregulates GM-CSF and IL-3 receptors by a mechanism which depends on new protein synthesis and downregulates G-CSF receptors by activation of protein kinase C (PCK). The leukemic cells from patients with acute or chronic leukemias have similar TNF receptor structures (MW 76 kD). Serum TNF levels increase in patients with both acute and chronic leukemias especially in those with advanced disease. The clinical application of TNF in association with GM-CSF or IL-3 may be of value for patients with AML.

Analysis of the TNF receptors on human leukaemia cells by affinity cross-linking.

Tumour necrosis factor (TNF) affects the growth of human leukaemic cells by different modes of action depending on the type of leukaemia involved. We have analysed the structure of TNF receptors on cells from different types of leukaemia, including acute lymphoblastic leukaemia (ALL), acute myeloblastic leukaemia (AML), chronic lymphocytic leukaemia (CLL), and chronic myelocytic leukaemia (CML) either in chronic phase (CML-CP) or blastic crisis (CML-BC). The affinity crosslinking technique showed the existence of TNF receptors on cells from all the leukaemic cases studied with similar receptor structures. The TNF receptor showed a molecular weight of 76 kD when examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. In conclusion, we provide evidence for existence of TNF receptors on several types of human leukaemia cells with an apparent molecular weight of 76 kD. Apparently, the discrepancy of TNF actions on the leukaemic growth are not related to the structure of TNF receptors.

Tumor necrosis factor downregulates granulocyte-colony-stimulating factor receptor expression on human acute myeloid leukemia cells and granulocytes.

Tumor necrosis factor (TNF) inhibits granulocyte-colony-stimulating factor (G-CSF)-induced human acute myeloid leukemia (AML) growth in vitro. Incubation of blasts from three patients with AML in serum-free medium with TNF (10(3) U/ml), and subsequent binding studies using 125I-G-CSF reveal that TNF downregulates the numbers of G-CSF receptors by approximately 70%. G-CSF receptor numbers on purified blood granulocytes are also downmodulated by TNF. Downregulation of G-CSF receptor expression becomes evident within 10 min after incubation of the cells with TNF at 37 degrees C and is not associated with an apparent change of the dissociation constant (Kd). The TNF effect does not occur at 0 degrees C and cannot be induced by IL-2, IL-6, or GM-CSF. TNF probably exerts its effect through activation of protein kinase C (PKC) as the TNF effect on G-CSF receptor levels can be mimicked by 12-O-tetradecanoylphorbol-13- acetate. The PKC inhibitor Staurosporine (Sigma Chemical Co., St. Louis, MO) as well as protease inhibitors can completely prevent G-CSF receptor downmodulation. Thus, it appears TNF may act as a regulator of G-CSF receptor expression in myeloid cells and shut off G-CSF dependent hematopoiesis. The regulatory ability of TNF may explain the antagonism between TNF and G-CSF stimulation.

Tumor necrosis factor regulates the expression of granulocyte-macrophage colony-stimulating factor and interleukin-3 receptors on human acute myeloid leukemia cells.

Tumor necrosis factor (TNF) acts as a potent enhancer of granulocyte-macrophage colony-stimulating factor (GM-CSF)- and interleukin-3 (IL-3)-induced human acute myeloid leukemia (AML) growth in vitro. We have analyzed the effects of TNF alpha on the expression of GM-CSF and IL-3 receptors on AML cells. Incubation of blasts from seven patients with AML in serum-free medium with TNF (10(3) U/mL) and subsequent binding studies using 125I-GM-CSF and 125I-IL-3 show that TNF increases the specific binding of GM-CSF (30% to 280%) and IL-3 (40% to 600%) in all cases. From Scatchard plot analysis it appears that TNF upregulates (1) low-affinity GM-CSF binding sites, (2) common high-affinity IL-3/GM-CSF binding sites, and (3) unique (non-GM-CSF binding) IL-3 binding sites. The effect of TNF is dose dependent and is half maximal at a concentration of 100 U/mL, and becomes evident at 18 hours of incubation with TNF at 37 degrees C, but not at 0 degree C. The GM-CSF dose-response curve of AML-colony-forming units plateaus at a higher level in the presence of TNF, which indicates that additional numbers of cells become responsive to GM-CSF. Incubation of AML blasts with the phorbol ester 12-0-tetradecanoylphorbol-13-acetate or formyl-Met-Leu-Phe (protein kinase C activators) does not influence GM-CSF receptor expression, suggesting that receptor upregulation by TNF is not mediated through activation of protein kinase C. On the other hand, the protein synthesis inhibitor cycloheximide abrogates receptor upregulation induced by TNF. In contrast to these findings in AML, TNF does not upregulate GM-CSF receptor numbers on blood granulocytes or monocytes. We conclude that TNF exerts positive effects on growth factor receptor expression of hematopoietic cells.

Common binding structure for granulocyte macrophage colony-stimulating factor and interleukin-3 on human acute myeloid leukemia cells and monocytes.

Granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) control the proliferation of human acute myeloid leukemia (AML) cells in vitro. Previously, we have shown that receptors for GM-CSF and IL-3 are often coexpressed on AML cells. Here we present experiments with purified AML blasts, normal monocytes, and granulocytes that were conducted to analyze the properties of GM-CSF and IL-3 binding proteins in more detail. On AML cells from eight cases we demonstrate two types of GM-CSF receptors: one with low affinity (dissociation constant [kd] 5.1 to 24.8 nmol/L) and one with a high affinity (kd 31 to 104 pmol/L). These AML cells also expressed high affinity receptors for IL-3 (kd 24 to 104 pmol/L). Cross-competition experiments showed that an excess concentration of nonlabeled IL-3 completely prevented the high affinity binding of radiolabled GM-CSF. This competition occurred at 37 degrees C as well as 4 degrees C. Low affinity GM-CSF binding was not affected by IL-3. Binding of radiolabeled IL-3 could be prevented by nonlabeled GM-CSF. In certain cases, this competition was complete, whereas in others only partial (49% to 77%) reduction of the radiolabeled IL-3 binding was seen. On the basis of these ligand binding features, we propose the existence of three receptor types on AML cells: (1) low affinity GM-CSF receptors that do not bind IL-3, (2) dual high affinity GM-CSF/IL-3 receptors, and (3) high affinity IL-3 receptors that do not bind GM-CSF. We could also demonstrate these receptor types on normal monocytes. In addition, a fourth type of receptor was apparent on normal granulocytes (4), incapable of binding IL-3 and with an intermediate affinity for GM-CSF (approximately 400 pmol/L). Chemical crosslinking showed that GM-CSF and IL-3 both bind to proteins with molecular weight values of 130, 105, and 75, which provides additional evidence for the existence of a common GM-CSF/IL-3 receptor complex.

Modulation of colony stimulating factor-(CSF) dependent growth of acute myeloid leukemia by tumor necrosis factor.

In this study we demonstrate that tumor necrosis factors (TNF alpha and TNF beta) are potent modulators of the in vitro proliferation of human AML cells. Blast cells from 11 cases of acute myeloblastic leukemia (AML) were incubated with recombinant TNF alpha or TNF beta in serum-free 3H-TdR uptake and colony culture systems in the presence or absence of recombinant interleukin-3 (IL-3), granulocyte macrophage colony-stimulating factor (GM-CSF), G-CSF, or M-CSF. Depending on the supplemented CSF, TNF could upregulate or suppress AML blast proliferation. Enhancement of AML growth by TNF was observed in the presence of IL-3 (in 9 of 11 cases in 3H-TdR assay; 6 of 9 cases in colony assay) and GM-CSF (in 8 of 11 cases in 3H-TdR assay; 4 of 9 cases in colony assay). In certain cases in which IL-3 or GM-CSF alone was unable to induce proliferative responses of AML cells, the simultaneous addition of TNF elicited colony growth and DNA synthesis suggesting a synergistic action between TNF and IL-3 or GM-CSF. In contrast, TNF suppressed G-CSF-induced growth (9 of 10 cases in 3H-TdR assay; 5 of 6 cases in colony assay). TNF could also stimulate DNA synthesis (in 2 of 11 cases) or colony formation (in 2 of 9 cases) in AML cultures without the addition of other growth factors. Experiments with neutralizing antibodies and specific radioimmunoassays for individual CSFs showed that the synergistic and antagonistic effects of TNF on AML growth could not be attributed to a release of one of these CSFs by the AML cells. The opposing consequence of exposure of AML blasts to TNF are of interest in view of our understanding of the pathophysiology of AML growth and the in vivo application of recombinant cytokines in AML patients.

Early diagnosis of cytomegalovirus infection in renal transplant and dialysis patients by DNA-DNA hybridisation assay.

One hundred forty-eight urine specimens were collected from 47 renal transplant and dialysis patients and screened for the detection of cytomegalovirus (CMV). Diagnosis of CMV infection was suggested in 17 out of 47 patients (36.2%) by more than one of the five methods used. DNA hybridisation assay (DNA HA) using 32P-labelled probe detected CMV DNA in 15 (31.9%) of 47 patients, whereas virus isolation on conventional tube cell cultures (CTC), immunofluorescence incorporating monoclonal antibodies on centrifugation vial cultures (IF), complement fixation test (CFT), and electron microscopy (EM) yielded positive results in only nine (19.2%), 12 (25.2%), 11 (23.4%), and one (2.1%) of 47 patients, respectively. The significance of these results obtained by DNA HA lies not only in the apparent increase in number of patients diagnosed, but also in both early and rapid detection of CMV DNA. More importantly, the DNA HA is highly specific in that it correlates accurately with clinical and laboratory data characteristic of CMV disease. In respect of clinically manifest CMV disease, the specificity of DNA HA, CTC, IF, CFT, and EM was 87.5, 43.7, 56.3, 43.7, and 6.3%, respectively. These advantages of DNA HA make it the test of choice for early diagnosis of CMV infections in immunosuppressed patients.

Maturation of human acute myeloid leukaemia in vitro: the response to five recombinant haematopoietic factors in a serum-free system.

The abilities of human recombinant IL-3, GM-CSF, G-CSF, M-CSF and Epo to induce maturation in human AML cells in vitro were investigated using cell specimens from 25 AML patients. The experiments were carried out under exactly defined serum-free culture conditions. In the absence of CSFs, monocytic and/or granulocytic maturation was detected in 14/25 cases. IL-3, GM-CSF, G-CSF and M-CSF elevated the proportions of monocyte/macrophages in 3/25, 2/25, 1/25 and 6/25 cases respectively, and increased the percentages of mature granulocytes in 2/25, 1/25, 1/25 and 0/25 cases, and if so only to a limited extent (values below 50%). The 3H-thymidine (3H-TdR) uptake studies revealed that IL-3, GM-CSF, G-CSF and M-CSF were efficient stimulators of DNA synthesis of AML cells in 19, 15, 13 and four of those cases, respectively. Thus, although the cells in most cases responded to CSFs by activation of DNA synthesis, they were unable to give rise to terminally differentiated stages. Provision of CSFs in combination was more frequently effective in enhancing maturation and also increased the magnitude of maturation response. Monocytic versus granulocytic maturation of AML cells after culture did not correlate with the FAB cytology nor with the type of CSF presented; but generally granulocytic maturation was an infrequent phenomenon. Epo stimulated erythroid differentiation and DNA synthesis only in the case of erythroleukaemia, but it had no effect on the cells of 10 other AML cases. Extrapolation of these in vitro findings would suggest that CSFs would have a limited therapeutic utility to induce AML cell maturation in vivo and that hazards of stimulating blast cell proliferation with these factors may be anticipated.

Combined use of sonication and monoclonal antibodies for the detection of early and late cytomegalovirus antigens in centrifugation cultures.

A total of 157 clinical specimens was inoculated into shell vials and conventional tube cell cultures containing confluent monolayers of human embryonic lung fibroblasts (HELF). Of 31 clinical cytomegalovirus (CMV) isolates, 30 specimens (96.8%) were positive by the immunofluorescence method on centrifugation vial cultures (CVC-IF), whereas the cytopathic effects (CPE) of CMV were detected in only 14 specimens (45.2%) in conventional tube cell cultures (CCC), P less than 0.001 and in 22 specimens (70.9%) in centrifugation vial cultures (CVC-P), P less than 0.1. Significantly more fluorescent foci were detected in centrifugation cultures inoculated with sonicated urine samples (P less than 0.001). CVC-P is more sensitive than CCC for the diagnosis of CMV (P less than 0.05), and a highly significant difference was observed when we compared the mean day to initial detection of CPE (P less than 0.001). For optimal detection of CMV, both CVC-IF and CVC-P should be used for the laboratory diagnosis of this virus infection.

New and sensitive standard cell culture technique for the detection of cytomegalovirus in clinical specimens.

Conventional tube cell culture has been recognised as the most sensitive technique available for human cytomegalovirus (HCMV) detection. Low-speed centrifugation of specimen inocula onto cell culture monolayers has been shown to increase the efficiency of infection with the AD 169 strain of HCMV. Therefore a centrifugal force of 900g for 1 hour at 37 degrees C was used to enhance the detection of HCMV cytopathic effect (CPE) in shell vials that contained circular coverslips with a monolayer of human embryonic lung (HEL) fibroblasts. Of 195 specimens, HCMV CPE was detected in 18 specimens (9.02%) on shell vial culture assay, whereas conventional tube cell culture was positive in only 13 specimens (6.6%). The shell vial culture assay was significantly more sensitive (P less than 0.05). Furthermore the development of the cytopathic effect on shell vial culture assay was significantly earlier (P less than 0.01) and more extensive. Urine samples were sonicated and the results obtained with immunofluorescence using human immune serum demonstrated that sonication increased both the intensity of fluorescence and number of fluorescent foci of HCMV-infected cells and also decreased the non-specific fluorescence of the background.

Human blood groups in Dakahlya, Egypt.

New data on blood groups among Egyptians (Dakahlya province) are obtained by studying eight blood group systems: ABO, Rhesus, MNSs, Kell, Duffy, Kidd, P and Lewis. Comparing our results with the data reported in neighbouring countries, we found in Egypt a high frequency of B, NS, cDe and K genes, a moderately high frequency of P and the presence of Fy gene. The Egyptian population appears as a mixture of African, Asiatic and Arabian characteristics.