Increased Plasma Human Immunodeficiency Virus Type 1 Burden following Antigenic Challenge with Pneumococcal Vaccine

Beda Brichacek 0 1 2 3 Susan Swindells 0 1 2 Edward N. Janoff 0 1 2 Samuel Pirruccello 0 1 2 Mario Stevenson 0 1 2 3 0 The Journal of Infectious Diseases 1996; 174:1191-9 1996 by The University of Chicago. All rights reserved. 0022-1899/96/7406-0007$01.00 1 Received 3 November 1995; revised 25 June 1996. Presented in part: 35th Interscience Conference on Antimicrobial Agents and Chemotherapy , San Francisco , September 1995. Written informed consent was obtained from all volunteers involved in this study, which was approved by the human subjects committees at the universi ties of Nebraska and Minnesota. Financial support: NIH (AI-30386, AI-32890 to M.S; AI-31373, DE-42600 to E.N.J.); VA Research Service (to E.N.J.). Infectious Disease Section (lllF) , One Veterans Dr., Minneapolis, MN 55417 2 Departments of Pathology and Microbiology and of Internal Medicine, University of Nebraska Medical Center, and Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha; Infectious Disease Section, Department of Medicine, VA Medical Center, and University of Minnesota School of Medicine , Minneapolis 3 Present affiliation: Program in Molecular Medicine, University of Massa chusetts Medical Center , Worcester, Massachusetts Primary factors that influence virus burden during human immunodeficiency virus type 1 (HIV1) disease progression remain a fundamental issue in pathogenesis. Because pneumococcal vaccine is routinely given to HIV-l-infected patients and replication of HIV-l within CD4 T cells is dependent on the activation state of the cell, it was investigated whether the T cell activation that enhances the immune response to vaccines may also enhance HIV-1 replication. Vaccination of asymptomatic HIV-l-infected patients led to rapid and significant increases in virus burden in some patients. The magnitude of these increases correlated significantly with the extent of the antibody response to the vaccination. Thus, antigenic stimulation by vaccines designed to prevent secondary infections may promote HIV-1 replication in certain patients. These findings provide a window for examining HIV -1 pathogenesis and for determining the appropriate preventive measures against other diseases in HIV -1- infected persons. - Vaccinations. Twelve asymptomatic HIV-1- infected and 18 HIV-1- seronegative control subjects were enrolled. Baseline char acteristics of vaccinees recruited from the HIV-1 clinic population of the University of Nebraska Medical Center are shown in table 1. Volunteers received an intramuscular injection of 0.5 mL of pneumococcal capsular polysaccharide vaccine (PNU-immune 23; Lederle Laboratories Division, American Cyanamid, Pearl River, NY) containing 25 J..lg of each of the 23 capsular polysaccharide types. A second control group was selected from among asymp tomatic HIV-I-infected patients, who received an intramuscular injection of 0.5 mL of subvirion influenza vaccine (Wyeth-Ayerst, Marietta, PA) containing 5 J..lg of hemagglutinin from each of the 3 influenza strains (AiTexas/36/9I, A1Beijing/353/89, and B/ Panama/45/90.23). The first control group of HIV-I-seronegative persons allowed a comparison of the vaccination response in these persons with those in HIV-seropositive persons. The second con trol group comprised HIV-I-seropositive persons who did not mount a significant response to another vaccine (influenza). This latter group allowed for comparison of virus load changes between individuals who did mount an immune response to vaccine chal lenge and those who did not. The second control group was also Clinical, immunologic, and virologic characteristics of HIV-1- seropositive asymptomatic needed to exclude indirect effects of study design (e.g., stress of clinic visits, natural variation in virus load) in contributing to the changes in virus load observed following vaccination. The demographics of HIV -1 - infected patients receiving pneumococcal or influenza vaccines were similar (mean age, 35.4 1.5 vs. 33.8 2.4 years; race, 92% vs. 88% Caucasian; and sex, 92% vs. 100% male, respectively). Vaccinated persons were examined at ~ 1, 3, 5, 9, and 12-16 weeks after vaccination for adverse reactions. At these intervals, blood samples were drawn for analysis of viral and immune param eters. For most analyses, "pre" represents the sampling point prior to vaccination, and "post" represents the sampling point at which the highest virus load was detected (the point selected in related studies [15, 16]). Quantitation of plasma virus burden by quantitative competi tive-polymerase chain reaction (QC-PCR) [19]. Aliquots ofpa tient plasma (0.6-1.0 mL) were adjusted to 1.5 mL with serum free RPMI (GIBCO BRL, Grand Island, NY), and virus particles were pelleted (90 min, 18,000 g, 4C). The virus pellet was resus pended in 100 p,L of serum-free RPMI containing 5 U of DNase 1 (Worthington Biochemical, Freehold, NJ) and incubated at 37C for 60 min. DNase-treated virus particles were again pelleted as above, and virions were solubilized in 400 p,L of RNAzo1 (Te1 Test "B," Friendswood, TX). We added 3 p,g of yeast tRNA (Sigma, 81. Louis), and 2000 RNA copies (1000 virions) of an HIV -1 integrase deletion mutant (MFA DIN 2) [20] as an internal competitor template were added to doubling dilutions of viral RNAzo1 lysate. The internal standard was distinguishable from target sequences due to the presence of an 89-bp deletion in the integrase coding region. The internal standard was quantitated by negative stain electron microscopy to determine the number of virus particles as well as by reverse transcription PCR amplifica tion of viral RNA followed by comparison with a known copy number dilution series generated by PCR amplification of DNA from a full-length HIV -1 molecular clone (HIV -1 MF) [20]. Target and internal standard virion RNAs were reverse-tran scribed in a 10-p,L reaction containing 44 pmol of an HIV -1 plus strand primer specific for HIV -1 integrase (5' -C49 17TGTCCCTGT AATAAACCC-3' (numbering according to Ratner et al. [21]). Reverse transcription proceeded at 42C for 17 min and was inacti vated at 99C for 6 min. Minus-strand primer (15 pmol) (5' G454 1CAGGAAGATGGCCAGTA-3') was added, and reverse transcripts were amplified by 35 cycles of PCR in which each cycle comprised a 30-s denaturation step (95C), a 30-s annealing step (58C), and a 60-s extension step (72C), followed by a single 7-min extension (72C). Southern blots of PCR products were visualized after hybridization to an HIV -1- specific oligonucleo tide probe (5'-G4585CTGCCATTGTCAGTATG-3') and quanti tated with a molecular phosphorimager (Molecular Dynamics SF, Sunnvale, CA) by volume integration as described [22]. Viral RNA copy number in the original plasma sample was calculated from the plasma dilution that resulted in a signal intensity equivalent to that obtained with the internal standard [19]. The sensitivity of this assay was 200 copies when c (...truncated)