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Antibodies against HTLV-III, neopterin levels in blood and urine, TH/TS ratio and hepatitis marker were determined in 34 clinically symptom-free persons known to be intravenous drug abusers. 15 persons were positive in the ELISA and Western-blot tests. There was a strong reaction to protein p24 compared with that to protein p41. In 12 of 14 persons who were antibody-positive the neopterin level in morning urine was elevated; an abnormal TH/TS ratio was present in nine of 13 persons. In future, determination of neopterin and of antibodies against certain proteins of HTLV-III may make it possible to provide a simple way of prognosticating on the course of an HTLV-III infection.

Emergence of viral agents in Europe is influenced by various factors. Climatic changes influencing possible vectors, insufficient vaccination, and travel of man and goods are among the most important reasons to explain these changes. Fever and arthralgia are the leading symptoms in infection with Dengue, Sindbis, or Chikungunya virus. In contrast, tick-born encephalitis (TBE), Toscana, or West Nile virus infections mainly lead to meningo-encephalitis. In Europe, hemorrhagic fever is caused by Crimean Congo and Hanta virus. Protective vaccines are available for emerging viral agents like TBE, influenza and measles.

Infectious agents may be divided according to their conventional classification starting with virus, bacteria, fungi, protozoa and worms. Of these agents only virus has been important for transmission by clotting product and due to donor selection, NAT (nucleic acid testing) and antibody screening, inactivation and removal, the transmission rate of transfusion relevant virus, such as HIV (human immunodeficiency virus), HTLV-I (human T leukemia virus type 1), HBV (hepatitis B virus) and HCV (hepatitis C virus) has been reduced to figures below 10 7 . In 2004 newly arisen has the risk of transmission of prion by blood transfusion and consecutively by plasma components as well, since two cases of transmission of vCJD by blood transfusion had been reported in UK [13, 17]. There are two new viruses and the vCJD agent which are giving concern to consider the safety of the administration of plasma component once more.

Risk of HIV transmission during the different modes of treatment depends on the HIV prevalence within the patient population and the instruments used during invasive procedures. Generally HIV may be transmitted from patient to the health care worker, from patient to patient and from health care worker to patient. Prevention of all modes of transmission is sterilisation or single use of equipment and if this is not possible proper disinfection of the equipment. HIV may be transmitted to patients by transplants that have not been sufficiently checked or pretreated. The most common route of HIV transmission is by stab wounds or puncture wounds by sharp instruments including needles. All reagents used for disinfection of other infectious agents are also valid for HIV. Infected staff should when ever possible avoid or refrain from performing operative procedures. HIV transmission is easily to prevent and part of all daily activities in medicine.

Genetic variation among HIV isolates creates challenges for their detection by serologic and genetic techniques. To characterize the sequence variation and its correlation to serologic diversity of HIV-1 Group O and HIV-2 isolates, samples were identified by differential reactivity in selected commercial and research assays. Analysis of sera from Equatorial Guinea (EG) led to identification of 4 HIV-1 Group O variants. Viral RNA, extracted from these samples was used to PCR amplify overlapping sequences of the entire envelope gene using multiple primer pairs. Sequence analysis indicated that the V3 loop nucleotide and protein sequences aligned more closely with HIVANT70 compared to other Group O sequences. The amino acid sequences at the octameric tip of the V3 loop were RIGPLAWY, RIGPMAWY, or GLGPLAVY. The tetrameric tip GPLA is represented only once in the published 1994 HIV database (Los Alamos) but was present in 2 of 4 of EG samples. The immuno-dominant region (IDR) sequences derived from EG sera were unique in that none of the sequences were completely homologous to other HIV-1 group O variants. Further, the HIV-1 group O sequence variation could be correlated with differential serologic reactivity using IDR peptides. Compared to HIV-1, the sequence information on HIV-2 isolates is relatively limited, though the HIV-2 isolates also show genetic variation similar to HIV-1. To further establish a correlation between the genetic diversity and serologic detection of HIV-2, plasma samples from Western Africa were evaluated. Eight samples were selected based on weak serologic reactivity to env proteins. PCR amplification and sequence analysis of the gag, env V3 loop, and env IDR regions indicated that the samples could be classified as subtypes A (4 samples), B (3 samples) and D (1 sample). Across the subtypes, there was conservation in the IDR region of the sequence WGCAFRQVCHT. This region is absolutely conserved among the majority of currently known HIV-2 and related SIV viruses (1994 HIV database). One subtype B sample had a unique sequence immediately adjacent to the IDR, however, this did not change the serologic detection using a HIV-2 IDR specific monoclonal antibody.

The aim of the study was to evaluate a new ELISA for detection of HIV-1, HIV-2 and HIV-1 subtype 0 (HIV-0) antibodies. The assay format is based on the antigen sandwich principle. To enable specific detection of HIV-0 antibodies, in addition to HIV-1 and HIV-2 antigens HIV-0 antigen is used for coating the solid phase and for the conjugate. The results show that all 12 HIV-0 samples tested were detected with a high degree of reactivity, as were all the 1,144 anti-HIV-1 and 424 anti-HIV-2 positive samples. The capacity of the test to enable early detection of seroconversions is equivalent to that of other sandwich ELISAs. The specificity of the assay was determined to be 99.89/99.94% (initial/after retest) using 58,366 samples, which is superior to the other ELISAs used for comparison. Even with difficult samples (i.e. samples of African origin, samples known to cause false-positive reactivity in different ELISAs, or samples containing potential interference factors) there were very few false-positive reactions. Therefore, the new assay is well suited for screening blood donations as well as for evaluating samples from patients of different geographic origin.

Estimating the risk of HIV transmission by blood or inactivated plasma transfusion. A discussion of the methods and techniques for the diagnosis of HIV infection in blood donors.Reports in German and English on this topic as well as own experiences of the authors.No specific selection criteria.Transfusion associated HIV infection may be prevented by donor selection, the very efficient anti-HIV testing, by p24-antigen testing that may detect some anti-HIV negative donations especially during the early time of seroconversion and by more recent introduced techniques like polymerase chain reaction (PCR) and signal amplification assay (SAA). PCR and SAA are under development and until now not sensitive and specific enough to contribute significantly to an earlier detection of HIV infected blood. Procedures for the inactivation of HIV in plasma or whole blood have been described. Until now use of psoralens, methylene blue or direct UV irradiation may reduce viral load but have not definitely been proven by clinical trials to be 100% efficient.To minimize transfusion associated HIV infection in future years reduction of total amount of transfused units, restriction to regional donor recruiting and further refinement of tests will be necessary. A 100% safety of blood transfusion for infectious agent cannot be achieved, especially considering new agents and further spread of until now geographically restricted viruses.

Risk of HIV transmission during the different modes of treatment depends on the HIV prevalence within the patient population and the instruments used during invasive procedures. Generally HIV may be transmitted from patient to the health care worker, from patient to patient and from health care worker to patient. Prevention of all modes of transmission is sterilisation or single use of equipment and if this is not possible proper disinfection of the equipment. HIV may be transmitted to patients by transplants that have not been sufficiently checked or pretreated. The most common route of HIV transmission is by stab wounds or puncture wounds by sharp instruments including needles. All reagents used for disinfection of other infectious agents are also valid for HIV. Infected staff should when ever possible avoid or refrain from performing operative procedures. HIV transmission is easily to prevent and part of all daily activities in medicine.

The epidemiology of HIV-1 and HIV-2 infection in 1989/90 shows a further spread of both viruses, especially in southern Europe, eastern Asia and central Africa. The sequence analysis of an immunodeficiency virus of a chimpanzee indicates the presence of SIV-1, in contrast to all other monkey isolates analyzed hitherto as members of SIV-2. The occurrence of eight newly HIV-infected hemophiliacs by one factor IX product gives rise to the question whether a 100% safety of blood products can be achieved. Analysis of HIV nucleic acids by PCR leads not to an improvement compared to the serological tests for the screening of blood donors. Despite all the efforts in the recent years, a safe and effective HIV vaccine will not be available in the near future.

Aufgrund der Nukleinsauren-Sequenzanalyse sind die bisher charakterisierten SIV-Isolate, dem menschlichen HIV-2 ahnlicher als dem HIV-1. Zu diesen als SIV-2 zusammengefasten Viren gehoren die aus der afrikanischen grunen Meerkatze [1], Rhesusaffe [2], Mangabe [3] und Mandrill [4]. Die Untersuchungen der verschiedenen Affen zeigte, das die Verbreitung von SIV-2 in Afrika wesentlich weitflachiger ist als die Durchseuchung der Menschen mit HIV-2.

Der virustatische Effekt des Interferons ist seit langem bekannt. Das auch das HIV-Virus durch Interferon in der Replikation inhibiert wird, konnte 1985 von Ho in vitro nachgewiesen werden. Auch konnte gezeigt werden, das Alpha-Interferon zu Regressionen des Kaposi-Sarkoms bei HIV-Infizierten fuhrt. In einigen Studien wurde dabei auch eine positive Beeinflussung der immunologischen Situation der HIV-Infizierten beobachtet.

Activities of the ecto-enzymes 5′-nucleotidase (5′-N) and phosphatase were determined on the surface of intact cells from 15 different established lines of human B- and T-lymphoblasts. Whereas all the lines express phosphatase, 10 of the lines were negative for 5′-N. 5′-N-negative cell lines are found among B as well as T cells, and they do not carry cryptic enzyme activity. In a 5′-N-positive line activity of this enzyme is correlated with growth showing a peak during the logarithmic phase. On the other hand, inhibition of 5′-N does not change the growth curve of this line. Neuraminidase treatment of the cell surface brings about an increase in phosphatase but not in 5′-N activity. 5′-N of two B-cell lines and of human peripheral blood lymphocytes shows complete crossreactivity with an antiserum obtained against human placental 5′-N. However, the enzyme of one lymphoma line with B-cell properties (EHR-A-Ramos) does not cross-react with this serum. The results are discussed with respect to suitability of these lymphoblast lines as model systems for the study of immunodeficiencies.

The presence of antibodies to HIV-1 (anti-HIV-1) was tested in 167 hemophiliacs surveyed and treated at Munich hemophilia center. Increasing numbers of HIV infected patients were observed in the years 1981 to 1986 from 0% to 51,5% (86 positive patients in January 1987 of 167 followed patients). Most of the seroconver-sions occured between 1982 and 1984. The 150 clinically severe affected hemophiliacs (F-VIII-levels up to 5% and need of replacement therapy) showed positive HIV-test results in 55,3% (83 patients) and negative results in 44,7% (67 patients). 5 patients died since 1981, one because of AIDS. 17 patients were not seen since 1984, 14 of those belong to the severly affected group, 12 of them were negative. Since spring 1985 only heat or chemically treated clotting factor preparations are used for substitution. Despite this still 5 seroconversions were observed. Two may be attributed to the use of a preparation heat inactivated in dry state, this preparation is no longer used. The other 3 seroconversions possibly were caused by an occasional use of an noninactivated preparation in the beginning of the change to inactivated clotting factor preparations. 38 of the anti-HIV-1 positive sera were tested for the presence of HIV-2 antibodies also. The methods were ELISA,immunofluorescence and immunoblot. HIV-2 (LAV-2) for these tests was kindly provided by L. Montagnier. Antibodies specific for HIV-2 antigens were not detected, but crossreactions were observed between anti-HIV-1 with HIV-2 antigens particularly epitopes on HIV-2-p27.The data indicate that the use of adequately inactivated clotting factors can prevent infection of hemophilia patients by this route and that HIV-2 was not present in the clotting factor preparations used for the substitution of this group of patients. The incidence of full blown AIDS since 1981 in our group of hemophiliacs is still low (1,2%).

Antibodies against HTLV-III, neopterin levels in blood and urine, TH/TS ratio and hepatitis marker were determined in 34 clinically symptom-free persons known to be intravenous drug abusers. 15 persons were positive in the ELISA and Western-blot tests. There was a strong reaction to protein p24 compared with that to protein p41. In 12 of 14 persons who were antibody-positive the neopterin level in morning urine was elevated; an abnormal TH/TS ratio was present in nine of 13 persons. In future, determination of neopterin and of antibodies against certain proteins of HTLV-III may make it possible to provide a simple way of prognosticating on the course of an HTLV-III infection.

Hamophile sind durch die Abhangigkeit von der Substitution mit menschlichen Faktor VIII- oder IX-Praparaten in der Gefahr, verschiedene infektios wirkende Agenzien ubertragen zu bekommen. Dies betrifft vor allem das Hepatitis B-Virus [1–5], die Hepatitis Non A/Non B-Viren [6–9] und andere Viren wie das Cytomegalie-virus und das Epstein-Barr-Virus. Ebenso besteht durch die Praparate die Moglichkeit einer Ubertragung von viralen Antigenen bzw, deren Antikorper [10].

Seit etwa eineinhalb Jahren werden bei uns gegen Hepatitis B-Marker seronegative Hamophiliepatienten geimpft. Bis heute sind es 13, zwischen 2 und 10 Jahren alt. Zwei von ihnen haben eine Hamophilie B und werden mit virusinaktiviertem Prothrombinkomplex bzw. mit hitzebehandeltem Faktor IX therapiert.

When ficoll purified peripheral blood lymphocytes were treated with fluorescein conjugated lectins from lentils (LCH), castor beans (RCA) and phaseolus coccineus beans (L- and E-PHA) for 15 min and the percentages of the cap forming cells were examined, the values of leukemic lymphocytes were reduced compared to the values obtained with normal lymphocytes. The reduction was more than half in patients with acute and chronic myelogenous leukemia and immunoblastoma, it was only one quarter in patients with chronic lymphocytic leukemia, Hodgkin's disease and lymphosarcoma. The lowest number of cap forming cells was found in lymphoblasts of established lymphoblastoid cell lines. The four different lectins showed nearly the same capacity in the induction of caps. After successive binding, the different lectins showed cocapping on the lymphocyte surface.

Die Herstellung von Gerinnungspraparaten ist von drei Hauptproblemen gekennzeichnet, die in zum Teil kontrar wirkender Richtung miteinander verknupft sind: 1. Faktormenge, d.h. fur die Produktion mus genugend Ausgangsplasma (2000–5000 Liter) vorhanden sein, um einen effizienten Herstellungsprozes einzuleiten [1]. 2. Faktorreinheit; die Faktor VIII- und IX-Praparate enthalten eine Vielzahl von anderen Proteinen des Plasmas. Die Herstellung und die anschliesende Virusinak-tivierung kann zur Proteindenaturierung fuhren. Uber die dauerhafte Zufuhr von strukturell veranderten Proteinen ist eine Immunmodulation im Hamophilie-Patienten zu erwarten. 3. Infektiositat. Die Infektiositat der Praparate wird beherrscht auf der einen Seite von dem Phanomen, das aufgrund der bestehenden Viramie bei einem Spender ein ganzer Pool mit einem Virus verseucht werden kann (NANB-Regel), auf der anderen Seite die meisten moglichen drastischen Verfahren zur Inaktivierung von Viren aufgrund der Labilitat der Gerinnungsfaktoren nicht angewendet werden konnen. Wegen der „Klebrigkeit“ von infektiosen Agentien an Proteinen und Proteinkomplexen konnen diese Partikel nicht durch einfache biochemische Methoden abgetrennt werden.