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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the absence of direct epidemiological evidence, molecular evolutionary studies of primate lentiviruses provide the most definitive information about the origins of human immunodeficiency virus (HIV)-1 and HIV-2. Related lentiviruses have been found infecting numerous species of primates in sub-Saharan Africa. The only species naturally infected with viruses closely related to HIV-2 is the sooty mangabey (Cercocebus atys) from western Africa, the region where HIV-2 is known to be endemic. Similarly, the only viruses very closely related to HIV-1 have been isolated from chimpanzees (Pan troglodytes), and in particular those from western equatorial Africa, again coinciding with the region that appears to be the hearth of the HIV-1 pandemic. HIV-1 and HIV-2 have each arisen several times: in the case of HIV-1, the three groups (M, N and O) are the result of independent cross-species transmission events. Consistent with the phylogenetic position of a 'fossil' virus from 1959, molecular clock analyses using realistic models of HIV-1 sequence evolution place the last common ancestor of the M group prior to 1940, and several lines of evidence indicate that the jump from chimpanzees to humans occurred before then. Both the inferred geographical origin of HIV-1 and the timing of the cross-species transmission are inconsistent with the suggestion that oral polio vaccines, putatively contaminated with viruses from chimpanzees in eastern equatorial Africa in the late 1950s, could be responsible for the origin of acquired immune deficiency syndrome.
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PMID:The origins of acquired immune deficiency syndrome viruses: where and when? 1140 34

In the light of the evidence and discussion presented during The Royal Society Discussion Meeting it seems to me that the oral polio vaccine (OPV) hypothesis for the origins of human immunodeficiency virus (HIV) and the acquired immune deficiency syndrome epidemic is less tenable now than one year earlier. The OPV hypothesis does not accord with HIV phylogenetic studies: the geographical correlation has been challenged; the testimony of those directly involved with OPV trial vaccines denies the use of chimpanzees, corroborating tests on the still-available vials of the CHAT vaccines, which contain neither simian immunodeficiency virus nor chimpanzee DNA. Yet one lesson to be learned from considering OPV as a source of HIV is how plausibly it might have happened and how cautious we need to be over introducing medical treatments derived from animal tissues, such as live, attenuated vaccines or xenotransplantation. To cast doubt on the OPV hypothesis is not to dismiss entirely the role of iatrogenic factors in HIV transmission from chimpanzees in the first instance, in HIV adaptation to onward transmission during its early phase in humans, or in the later spread of HIV to patients, for example, with haemophilia. To reduce the argument over the origins of HIV to the 'OPV hypothesis' versus the 'cut-hunter hypothesis' is an oversimplistic and false antithesis. Both natural and iatrogenic transmission of many retroviruses, including HIV, have been thoroughly documented and are not mutually exclusive. Exactly how, when and where the first human(s) became infected with the progenitor of HIV-1 group M, which gave rise to the pandemic strain, is likely, however, to remain a matter of conjecture.
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PMID:Natural and iatrogenic factors in human immunodeficiency virus transmission. 1140 45

The action of immunomodulators, purified staphylococcal toxoid (PST) and lycopid, on secondary immunodeficiency state developing during infection caused by Coxsackie virus B3 was studied. This defect was manifested by delayed hypersensitivity to sheep red blood cells (SRBC) and the suppression of neutralizing antibodies to poliomyelitis virus. Depending on the scheme of the experiment, PST normalized the defects of immune response to SRBC or poliovirus, increased suppression or showed no activity. Lycopid corrected the defects of humoral response to SRBC. The combination of PST and lycopid was found to produce no increase of suppression. The suggestion was made on the expediency of combination of two (and probably more) immunomodulators for increasing the efficiency of correction of secondary immunodeficiency.
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PMID:[Correction of immune response using purified staphylococcal toxoid and likopid in the secondary immunodeficiency induced by Coxsackie virus B3]. 1187

Specific humoral immunity, total immune status and typing of HLA antigens, class 1, in loci A and B were studied in children with vaccine-associated paralytic poliomyelitis (VAPP). The immune status investigation revealed that changes in the content of serum immunoglobulins were most frequent. Out of 8 examined children, 5 children had IgA deficiency and 1 child had total variable immunodeficiency. In one case disturbances in cell-mediated immunity prevailed. Tissue typing revealed the presence of HLA A2 and B44 in 5 out of 6 examined children, which considerably exceeded their average occurrence among the Belorussian population. In spite of frequent detection of immunological disturbances in VAPP patients, out of 38 serologically examined children 36 (95%) were found to have virus-neutralizing serum antibodies to poliovirus, which was indicative of the capacity of their immune system for response to the administration of vaccine virus. To minimize the risk of VAPP in children and to achieve the goal of poliomyelitis eradication the combined immunization scheme consisting of 1-3 vaccinations with inactivated poliovaccine with subsequent administration of oral vaccine prepared from attenuated Sabin viruses is regarded as most promising.
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PMID:[Characterization of the immune status of patients with vaccine-associated poliomyelitis]. 1204 52

The practical elements of BCG vaccination in neonates are used in most developing countries are outlined. The World Health Organization that all neonates be vaccinated, as well as all unvaccinated children when they present for health care, without prior PPD testing. BCG vaccine is a live attenuated TB vaccine in lyophilized state, so it must be kept cold and away from light. After redissolving, the vaccine is given intradermally with a 0.45% 10 mm needle either on the volar left forearm or the posterior left arm, at a consistent site in each country. The dose must be 0.05 ml for babies 1 year old, and 0.1 ml for older children. A wheal is formed that disappears in 30 minutes, followed by a red nodule in 3-4 weeks. The depressed scar is evidence of vaccination. In rare cases, lymphadenitis may appear, sometimes with a fistula. This is more likely when 0,1 ml is given to infants, the vaccine is not diluted properly, or the injection is given too deeply. While immunodeficiency is considered a contraindication for BCG vaccination, infants born to HIV-positive mothers have received it without adverse effects. Other immunizations such as oral polio may be given concomitantly. Verification of BCG vaccination is by presence of the scar or PPD testing. About 30-50% of children entering school are still positive; negative children may be revaccinated.
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PMID:BCG vaccination. 1234 45

To obtain insight into the mechanism(s) of posttransplantation humoral immunodeficiency, we evaluated factors affecting serum antibody levels against polio, tetanus, Haemophilus influenzae, and Streptococcus pneumoniae in 87 patients. Patients with hematologic malignancies were randomized to receive marrow versus blood stem cells, which contain approximately 10 times more lymphocytes than marrow. Blood stem cell recipients did not have higher antibody levels than marrow recipients. Recipient pretransplantation antibody levels were correlated with the posttransplantation levels, especially in the first 6 months after transplantation when the correlation coefficients typically exceeded 0.6. Donor pretransplantation antibody levels had less of a correlation with posttransplantation levels in the recipient. Patient or donor age, total body irradiation, and graft-versus-host disease or its treatment appeared to have no effect. In conclusion, antibody levels in the first year after transplantation are affected primarily by pretransplantation antibody levels in the recipient and, to a lesser degree, in the donor. These findings suggest that immunization of the recipient and the donor before transplantation may be more effective in improving antibody immunity after transplantation than manipulating graft-versus-host disease, changing conditioning, or increasing the number of lymphocytes in the graft.
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PMID:Factors affecting antibody levels after allogeneic hematopoietic cell transplantation. 1250 30

Several virus inactivation procedures like heat treatment, gamma irradiation and chemical sterilization are used to increase the safety of bone tissue transplants. In this study we present data on the virus-inactivating effect of heat disinfection on human femoral heads, using the Marburg bone bank system 'Lobator sd-2'. Three enveloped viruses (human immunodeficiency virus type 2 [HIV-2], bovine viral diarrhoea virus as a model for Hepatitis C virus [HCV], and the herpesvirus pseudorabies virus), and three non-enveloped viruses (hepatitis A virus, poliomyelitis virus, and bovine parvovirus) were investigated. In a model system the central part of human femoral heads was contaminated with the respective cell-free virus suspension, establishing a direct contact between virus and native bone tissue. The core temperature in the femoral heads during the sterilization process was determined in additional model experiments. A temperature of 82.5 degrees C, given by the manufacturer as the effective temperature for virus inactivation, was maintained for at least 15 min in decartilaged femoral heads with a diameter of < or = 56 mm. Heat treatment using the Lobator sd-2 inactivated all viruses in human femoral heads below the detection limit (at least by a factor of > or =4 log(10)). By combining a well-focussed anamnesis of the donors and serological testing for relevant infection markers (anti-HIV-1/2, HBsAg, anti-HBcore, anti-HCV, TPHA) with heat treatment of femoral heads in the Lobator sd-2 system, a high safety level is achieved. To further increase virus safety of cadaveric bone transplants, it is recommended that multi-organ donors are tested by nucleic acid testing (i.e. polymerase chain reaction) for HIV, HBV and HCV genome.
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PMID:Virus inactivation in bone tissue transplants (femoral heads) by moist heat with the 'Marburg bone bank system'. 1262 62

This paper reviews the English language literature on the safety, immunogenicity and effectiveness in children infected with the human immunodeficiency virus (HIV) of vaccines currently recommended by WHO for use in national immunization programmes. Immunization is generally safe and beneficial for children infected with HIV, although HIV-induced immune suppression reduces the benefit compared with that obtained in HIV-uninfected children. However, serious complications can occur following immunization of severely immunocompromised children with bacillus Calmette-Gu rin (BCG) vaccine. The risk of serious complications attributable to yellow fever vaccine in HIV-infected persons has not been determined. WHO guidelines for immunizing children with HIV infection and infants born to HIV-infected women differ only slightly from the general guidelines. BCG and yellow fever vaccines should be withheld from symptomatic HIV-infected children. Only one serious complication (fatal pneumonia) has been attributed to measles vaccine administered to a severely immunocompromised adult. Although two HIV-infected infants have developed vaccine-associated paralytic poliomyelitis, several million infected children have been vaccinated and the evidence does not suggest that there is an increased risk. The benefits of measles and poliovirus vaccines far outweigh the potential risks in HIV-infected children. The policy of administering routine vaccines to all children, regardless of possible HIV exposure, has been very effective in obtaining high immunization coverage and control of preventable diseases. Any changes in this policy would have to be carefully examined for a potential negative impact on disease control programmes in many countries.
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PMID:Immunization of children at risk of infection with human immunodeficiency virus. 1264 Apr 78

Despite strong evidence to the contrary, speculation continues that the AIDS virus, human immunodeficiency virus type 1 (HIV-1), may have crossed into humans as a result of contamination of the oral polio vaccine (OPV). This 'OPV/AIDS theory' claims that chimpanzees from the vicinity of Stanleyville--now Kisangani in the Democratic Republic of Congo--were the source of a simian immunodeficiency virus (SIVcpz) that was transmitted to humans when chimpanzee tissues were allegedly used in the preparation of OPV. Here we show that SIVcpz is indeed endemic in wild chimpanzees of this region but that the circulating virus is phylogenetically distinct from all strains of HIV-1, providing direct evidence that these chimpanzees were not the source of the human AIDS pandemic.
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PMID:Origin of AIDS: contaminated polio vaccine theory refuted. 1510 67

We determined the complete genomic sequences of nine type 1 immunodeficient vaccine-derived poliovirus (iVDPV) isolates obtained over a 337-day period from a poliomyelitis patient from Taiwan with common variable immunodeficiency. The iVDPV isolates differed from the Sabin type 1 oral poliovirus vaccine (OPV) strain at 1.84% to 3.15% of total open reading frame positions and had diverged into at least five distinct lineages. Phylogenetic analysis suggested that the chronic infection was initiated by the fifth and last OPV dose, given 567 days before onset of paralysis, and that divergence of major lineages began very early in the chronic infection. Key determinants of attenuation in Sabin 1 had reverted in the iVDPV isolates, and representative isolates of each lineage showed increased neurovirulence for PVR-Tg21 transgenic mice. None of the isolates had retained the temperature-sensitive phenotype of Sabin 1. All isolates were antigenic variants of Sabin 1, having multiple amino acid substitutions within or near neutralizing antigenic sites 1, 2, and 3a. Antigenic divergence of the iVDPV variants from Sabin 1 followed two major independent evolutionary pathways. The emergence of distinct coreplicating lineages suggests that iVDPVs can replicate for many months at separate sites in the gastrointestinal tract. Some isolates had mosaic genome structures indicative of recombination across and within lineages. iVDPV excretion apparently ceased after 30 to 35 months of chronic infection. The appearance of a chronic VDPV excretor in a tropical, developing country has important implications for the strategy to stop OPV immunization after eradication of wild polioviruses.
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PMID:Intratypic recombination among lineages of type 1 vaccine-derived poliovirus emerging during chronic infection of an immunodeficient patient. 1618 64


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