Lack of Prophylactic Efficacy of Oral Maraviroc in Macaques despite High Drug Concentrations in Rectal Tissues

Maraviroc (MVC) is a potent CCR5 coreceptor antagonist that is in clinical testing for daily oral pre-exposure prophylaxis (PrEP) for HIV prevention. We used a macaque model consisting of weekly SHIV_162p3 exposures to evaluate the efficacy of oral MVC in preventing rectal SHIV transmission. MVC dosing was informed by the pharmacokinetic profile seen in blood and rectal tissues and consisted of a human-equivalent dose given 24 h before virus exposure, followed by a booster postexposure dose. In rectal secretions, MVC peaked at 24 h (10,242 ng/ml) with concentrations at 48 h that were about 40 times those required to block SHIV infection of peripheral blood mononuclear cells (PBMCs) in vitro. Median MVC concentrations in rectal tissues at 24 h (1,404 ng/g) were 30 and 10 times those achieved in vaginal or lymphoid tissues, respectively. MVC significantly reduced macrophage inflammatory protein 1β-induced CCR5 internalization in rectal mononuclear cells, an indication of efficient binding to CCR5 in rectal lymphocytes. The half-life of CCR5-bound MVC in PBMCs was 2.6 days. Despite this favorable profile, 5/6 treated macaques were infected during five rectal SHIV exposures as were 3/4 controls. MVC treatment was associated with a significant increase in the percentage of CD3⁺/CCR5⁺ cells in blood. We show that high and durable MVC concentrations in rectal tissues are not sufficient to prevent SHIV infection in macaques. The increases in CD3⁺/CCR5⁺ cells seen during MVC treatment point to unique immunological effects of CCR5 inhibition by MVC. The implications of these immunological effects on PrEP with MVC require further evaluation.     

Rhesus Macaques Infected with Macrophage-Tropic Simian Immunodeficiency Virus (SIVmacR71/17E) Exhibit Extensive Focal Segmental and Global Glomerulosclerosis

We previously showed that inoculation of rhesus macaques with molecularly cloned lymphocytetropic simian immunodeficiency virus (SIV_mac239) results in SIV-associated nephropathy (SIVAN) and that the glomerulosclerotic lesions were associated with the selection of macrophagetropic (M-tropic) variants (V. H. Gattone et al., AIDS Res. Hum. Retroviruses 14:1163–1180, 1998). In the present study, seven rhesus macaques were inoculated with M-tropic SIV_macR71/17E, and the renal pathology was examined at necropsy. All SIV_macR71/17E-infected macaques developed AIDS, and most developed other systemic complications, including SIV-induced encephalitis and lentivirus interstitial pneumonia. There was no correlation between the length of infection (42 to 97 days), circulating CD4⁺ T-cell counts, and renal disease. Of the seven macaques inoculated with SIV_macR71/17E, five developed significant mesangial hyperplasia and expansion of matrix and four were clearly azotemic (serum urea nitrogen concentration of 40 to 112 mg/dl). These same five macaques developed focal segmental to global glomerulosclerotic lesions. Increased numbers of glomerular CD68⁺ cells (monocytes/macrophages) were found in glomeruli but not the tubulointerstitium of the macaques inoculated with SIV_macR71/17E. All macaques had glomerular deposits of immunoglobulin G (IgG), IgM, and tubuloreticular inclusions, and six of seven had IgA deposition. However, there was no correlation between the presence of circulating anti-SIV_mac antibodies, immunoglobulin deposition, and glomerular disease. Tubulointerstitial infiltrates were mild, with little or no correlation to azotemia, while microcystic tubules were evident in those with glomerulosclerosis or azotemia. The four most severely affected macaques were positive for diffuse glomerular immunostaining for viral core p27 antigen, and there was intense staining in the glomeruli of the two macaques with the most severe glomerulosclerosis. Viral sequences were isolated from glomerular and tubulointerstitial fractions from macaques with severe glomerulosclerosis but only from the tubulointerstitial compartment of those that did not develop glomerulosclerosis. Interviral recombinant viruses generated with env sequences isolated from glomeruli confirmed the M-tropic nature of the virus found in the glomeruli. The correlation between the increased number of CD68⁺ cells (monocytes/macrophages) in the glomeruli, the localization of p27 antigen in the glomeruli, and the glomerular pathology confirms and extends our previous observations of an association between glomerular infection and infiltration by M-tropic virus and SIVAN.     

Simian-Human Immunodeficiency Virus (SHIV) Containing the nef/Long Terminal Repeat Region of the Highly Virulent SIVsmmPBj14 Causes PBj-Like Activation of Cultured Resting Peripheral Blood Mononuclear Cells, but the Chimera Showed No Increase in Virulence

SIV_smmPBj14 is a highly pathogenic lentivirus which causes acute diarrhea, rash, massive lymphocyte proliferation predominantly in the gastrointestinal tract, and death within 7 to 14 days. In cell culture, the virus has mitogenic effects on resting macaque T lymphocytes. In contrast, SIV_mac239 causes AIDS in rhesus macaques, generally within 2 years after inoculation. In a previous study, replacement of amino acid residues 17 and 18 of the Nef protein of SIV_mac239 with the corresponding amino acid residues of the Nef protein of SIV_smmPBj14 yielded a PBj-like virus that caused extensive activation of resting T lymphocytes in cultures and acute PBj-like disease when inoculated into pig-tailed macaques. This study suggested that nef played a major role in both processes. In this study, we replaced the nef/long terminal repeat (LTR) region of a nonpathogenic simian-human immunodeficiency virus (SHIV), SHIV_PPc, with the corresponding region from SIV_smmPBj14 and examined the biological properties of the resultant virus. Like SIV_smmPBj14, SHIV_PPcPBjnef caused massive stimulation of resting peripheral blood mononuclear cells (PBMC), which then produced virus in the absence of extraneous interleukin 2. However, when inoculated into macaques, the virus failed to replicate productively or cause disease. Thus, while these results confirmed that the nef/LTR region of SIV_smmPBj14 played a major role in the activation of resting PBMC, duplication of the cellular activation process in macaques may require a further interaction between nef and the envelope glycoprotein of simian immunodeficiency virus because SHIV, containing the envelope of human immunodeficiency virus type 1, failed to cause activation in vivo.     

Peripheral NKT Cells in Simian Immunodeficiency Virus-Infected Macaques

NKT cells are a specialized population of T lymphocytes that have an increasingly recognized role in immunoregulation, including controlling the response to viral infections. The characteristics of NKT cells in the peripheral blood of macaques during simian immunodeficiency virus (SIV) or chimeric simian/human immunodeficiency virus (HIV) (SHIV) infection were assessed. NKT cells comprised a mean of 0.19% of peripheral blood lymphocytes across the 64 uninfected macaques studied. Although the range in the percentages of NKT cells was large (0 to 2.2%), levels were stable over time within individual macaques without SIV/SHIV infection. The majority of NKT cells in macaques were CD4⁺ (on average 67%) with smaller populations being CD8⁺ (21%) and CD4/CD8 double positive (13%). A precipitous decline in CD4⁺ NKT cells occurred in all six macaques infected with CXCR4-tropic SHIV_mn229 early after infection, with a concomitant rise in CD8⁺ NKT cells in some animals. The depletion of CD4⁺ NKT cells was tightly correlated with the depletion of total CD4⁺ T cells. R5-tropic SIV_mac251 infection of macaques resulted in a slower and more variable decline in CD4⁺ NKT cells, with animals that were able to control SIV virus levels maintaining higher levels of CD4⁺ NKT cells. An inverse correlation between the depletion of total and CD4⁺ NKT cells and SIV viral load during chronic infection was observed. Our results demonstrate the infection-driven depletion of peripheral CD4⁺ NKT cells during both SHIV and SIV infection of macaques. Further studies of the implications of the loss of NKT cell subsets in the pathogenesis of HIV disease are needed.     

Development of a chronically catheterized maternal-fetal macaque model to study in utero mother-to-fetus HIV transmission: A preliminary report

Abstract: The lack of a representative animal model that permits frequent in utero fetal blood sampling is a major limiting factor for the study of maternal-fetal HIV transmission. Therefore, we have developed a maternal-fetal virus infection model using chronically catheterized macaques to simultaneously study the time-course of viral infection in the mother and the response of the fetus to maternal HIV infection. Pregnant macaques were infected with 10³ infectious units of HIV-2₂₈₇; every 3 days blood samples from both the mother and the fetus as well as amniotic fluid samples were collected. We found a varying degree of peak and time-to-peak virus load, virus-infected PBMCs, and free virus (determined by QC-RNA-PCR method) in maternal blood. Two of the three mothers with more than 10⁸ copies of viral RNA/ml of plasma at peak viremia transmitted the virus to their fetuses at about 14 days post-infection. As observed with HIV-2₂₈₇ infected mothers, virus-infected fetuses also produced a rapid rate of CD4⁺ cell decline in utero.     

Pilot study of treatment of biochemotherapy-refractory stage IV melanoma patients with autologous dendritic cells pulsed with a heterologous melanoma cell line lysate

Eleven AJCC stage IV melanoma patients with progressive disease after treatment with biochemotherapy were treated with autologous dendritic cells pulsed with heterologous tumor cell lysates. The vaccine used mature DCs (CD1a⁺⁺⁺, CD40⁺⁺, CD80⁺⁺, CD83⁺, and CD86⁺⁺⁺) generated from peripheral blood monocytes in the presence of GM-CSF and IL-4. After 7 days, DCs were matured with a defined cocktail of cytokines (IL-1+IL-6+TNF-+PGE₂) and simultaneously pulsed with lysates of heterologous melanoma cell lines, for 2 days. A total of 4×10⁶ DCs was injected monthly under ultrasound control in an inguinal lymph node of normal appearance. The study was closed when all patients died as a consequence of tumor progression. No sign of toxicity was observed during the study. One patient experienced a partial response lasting 5 months, and two patients showed a mixed response which lasted 3 months. The median survival of the whole group was 7.3 months (range 3–14 months). This vaccination program had specific antitumoral activity in highly pretreated and large tumor burden stage IV melanoma patients and was well tolerated. The clinical responses and the median survival of the group of patients, together with the low toxicity of our DC vaccine, suggest that this approach could be applied to earlier AJCC stage IV melanoma patients.     

Aging Decreases Oxidative Metabolism and the Release and Synthesis of Acetylcholine

Acetylcholine (ACh) synthesis in vivo is known to decrease during the aging process (senescence). To elucidate the molecular mechanism(s) of this age-related decline, we studied brain slices from 3-, 10-, and 30-month-old mice of two strains (C57B1 and Balb/c). In low K⁺ media, oxidative metabolism as measured by ¹⁴CO₂ production decreased with aging from 100% (3 months) to 85% (10 months) or 71% (30 months) whether [U^?14C]glucose, [3,4-¹⁴C]glucose, or [l-¹⁴C]pyruvate was the substrate. In the aged brain (3 months) the increase in ¹⁴CO₂ production with K⁺ stimulation was about twofold higher than in the young brain (3 months). Thus, in high K⁺ media, only slight decreases (<10%) in oxidative metabolism occurred with aging. Changes in ACh synthesis paralleled the decreases in ¹⁴CO₂ production. Synthesis of [¹⁴C]ACh from [U-¹⁴C]glucose in low K⁺ media declined from 100% (3 months) to 85% (10 months) or 66% (30 months), while in high K⁺ media only slight decreases (<10.5%) occurred with aging. The Ca²⁺-dependent, K⁺-stimulated release of [¹⁴C]ACh declined from 100% (3 months) to 58% (10 months) or 25% (30 months). Only the decrease in the release of ACh declined to the same extent as the reduced in vivo synthesis of ACh with aging. The results suggest that decreases in oxidative metabolism, ACh synthesis, and in the release of ACh contribute to a reduction in cholinergic function in the senescent brain.     

Oral Immunization of Macaques with Attenuated Vaccine Virus Induces Protection against Vaginally Transmitted AIDS

The chimeric simian-human immunodeficiency virus SHIV_KU-1, bearing the envelope of human immunodeficiency virus type 1 (HIV-1), causes fulminant infection with subtotal loss of CD4⁺ T cells followed by development of AIDS in intravaginally inoculated macaques and thus provides a highly relevant model of sexually transmitted disease caused by HIV-1 in human beings. Previous studies using this SHIV model had shown that the vpu and nef genes were important in pathogenesis of the infection, and so we deleted portions of these genes to create two vaccines, ΔvpuΔnefSHIV-4 (vaccine 1) and ΔvpuSHIV_PPc (vaccine 2). Six adult macaques were immunized subcutaneously with vaccine 1, and six were immunized orally with vaccine 2. Both viruses caused infection in all inoculated animals, but whereas vaccine 1 virus caused only a nonproductive type of infection, vaccine 2 virus replicated productively but transiently for a 6- to 10-week period. Both groups were challenged 6 to 7 months later with pathogenic SHIV_KU-1 by the intravaginal route. All four unvaccinated controls developed low CD4⁺ T-cell counts (<200/μl) and AIDS. The 12 vaccinated animals all became infected with SHIV_KU-1, and two in group 1 developed a persistent productive infection followed by development of AIDS in one. The other 10 have maintained almost complete control over virus replication even though spliced viral RNA was detected in lymph nodes. This suppression of virus replication correlated with robust antiviral cell-mediated immune responses. This is the first demonstration of protection against virulent SHIV administered by the intravaginal route. This study supports the concept that sexually transmitted HIV disease can be prevented by parenteral or oral immunization.     

Pharmacological study of the second messengers that control rectal ion and fluid transport in the desert locust (Schistocerca gregaria)

The involvement of second messengers in modulating Schistocerca gregaria rectal ion and fluid transport was investigated using two in vitro bioassay systems: everted rectal sacs and rectal flat sheets. Various agents known to block or activate specific signal transduction pathways were employed in these bioassays. Cyclic AMP stimulated rectal fluid reabsorption (J_v) and Cl⁻ transport (I_sc) to the same extent as aqueous extracts of corpus cardiacum storage lobes. Cyclic GMP also partially (50%) stimulated both rectal J_v and I_sc. Exogenous Ca²⁺ was not required for the maintenance of rectal transport, indeed Ca²⁺ free conditions increased the amount of stimulatable J_v. There was some evidence indicating intracellular Ca²⁺ may play a minor role in controlling rectal transport. The phospholipase C mediated signal transduction pathway was not involved with the stimulation of rectal transport, and appeared to have an inhibitory role. Neuroparsins, antidiuretic neuropeptides from Locusta migratoria, showed no activity upon either S. gregaria rectal ion or fluid transport. The findings of this study show that the two closely related insects possess discrete antidiuretic factors which stimulate rectal transport via different signal transduction pathways. © 1996 Wiley-Liss, Inc.     

Subacute SARS-CoV-2 replication can be controlled in the absence of CD8+ T cells in cynomolgus macaques

SARS-CoV-2 infection presents clinical manifestations ranging from asymptomatic to fatal respiratory failure. Despite the induction of functional SARS-CoV-2-specific CD8⁺ T-cell responses in convalescent individuals, the role of virus-specific CD8⁺ T-cell responses in the control of SARS-CoV-2 replication remains unknown. In the present study, we show that subacute SARS-CoV-2 replication can be controlled in the absence of CD8⁺ T cells in cynomolgus macaques. Eight macaques were intranasally inoculated with 10⁵ or 10⁶ TCID₅₀ of SARS-CoV-2, and three of the eight macaques were treated with a monoclonal anti-CD8 antibody on days 5 and 7 post-infection. In these three macaques, CD8⁺ T cells were undetectable on day 7 and thereafter, while virus-specific CD8⁺ T-cell responses were induced in the remaining five untreated animals. Viral RNA was detected in nasopharyngeal swabs for 10–17 days post-infection in all macaques, and the kinetics of viral RNA levels in pharyngeal swabs and plasma neutralizing antibody titers were comparable between the anti-CD8 antibody treated and untreated animals. SARS-CoV-2 RNA was detected in the pharyngeal mucosa and/or retropharyngeal lymph node obtained at necropsy on day 21 in two of the untreated group but undetectable in all macaques treated with anti-CD8 antibody. CD8⁺ T-cell responses may contribute to viral control in SARS-CoV-2 infection, but our results indicate possible containment of subacute viral replication in the absence of CD8⁺ T cells, implying that CD8⁺ T-cell dysfunction may not solely lead to viral control failure.     

Synchronous mucinous adenocarcinoma of the rectosigmoid seeding onto a pre-existing anal fistula

Carcinoma within a long-standing fistula-in-ano is rare and may be defined by specific neoplastic involvement of the fistulous track in the absence of rectal mucosal carcinoma. The presence of a carcinoma of mucinous histology occurring synchronously in the perianal region and the colon is exceptionally rare. We present a case with a review of the literature concerning its aetiopathogenesis and treatment. A 72-year-old man with a 2 months history of dark red rectal bleeding and mucus per rectum with alternating constipation and diarrhoea, was observed. Clinical examination and a barium enema showed a perianal fistula and an annular stenosing lesion of the rectosigmoid. Preoperative CT scan confirmed the colonic lesion. Colonic resection and wide fistula excision were performed. Histology showed an adenocarcinoma with a clear resection margins. The fistula also showed a similar histology. Chemoradiation (5-Fluorouracil (425 mg/m²) and Leucovorin (20 mg/m²) with 4500 cGy external beam radiotherapy was utilized. Subsequent clinical follow-up and CT examination of the patient has not revealed recurrent disease at 14 months.     

Intra-amniotic inoculation of pigtailed macaque (Macaca nemestrina) fetuses with SIV and HIV-1

Six pregnant pigtailed macaques (Macaca nemestrina) were inoculated intra-amniotically (i.a.) with SIV_Mne. All became viremic and seroconverted; three viable offspring were SIV-positive and at autopsy showed disseminated viral infection; one of three abortuses had SIV-infected thymic macrophages. Three of five pregnant macaques inoculated i.v. and/or i.a. with HIV-1_LAI became virus-positive, and four seroconverted, suggesting fetal-maternal transmission. One abortus had HIV-1-antigen in lymph nodes and brain; one infant, culture-positive at birth, died at age 11 days of disseminated HIV-1 infection.     

Clinical and Pathologic Features of Cynomolgus Macaques (Macaca fascicularis) Infected with Aerosolized Yersinia pestis

Since the anthrax attacks of 2001, the emphasis on developing animal models of aerosolized select agent pathogens has increased. Many scientists believe that nonhuman primate models are the most appropriate to evaluate pulmonary response to, vaccines for, and treatments for select agents such as Yersinia pestis (Y. pestis), the causative agent of plague. A recent symposium concluded that the cynomolgus macaque (Macaca fascicularis) plague model should be characterized more fully. To date, a well-characterized cynomolgus macaque model of pneumonic plague using reproducible bioaerosols of viable Y. pestis has not been published. In the current study, methods for creating reproducible bioaerosols of viable Y. pestis strain CO92 (YpCO92) and pneumonic plague models were evaluated in 22 Indonesian-origin cynomolgus macaques. Five macaques exposed to doses lower than 250 CFU remained free of any indication of plague infection. Fifteen macaques developed fever, lethargy, and anorexia indicative of clinical plague. The 2 remaining macaques died without overt clinical signs but were plague-positive on culture and demonstrated pathology consistent with plague. The lethal dose of plague in humans is reputedly less than 100 organisms; in this study, 66 CFU was the dose at which half of the macaques developed fever and clinical signs (ED₅₀), The Indonesian cynomolgus macaque reproduces many aspects of human pneumonic plague and likely will provide an excellent model for studies that require a macaque model.Yersinia pestis is the causative agent of plague. Likely more people worldwide have died from Y. pestis infections than from any other single infectious disease.^26,27 Bubonic plague, the most common form of the disease, results when the bacterium is inoculated into the skin, typically by means of flea bites. The resulting cutaneous infection spreads to local lymph nodes; the swollen lymph nodes are known as bubos and often serve as a source of systemic infection. Although less common, the bacterium also can spread by aerosol, causing pneumonic plague. Pneumonic plague can result from pulmonary spread of systemic infection or from deliberate dissemination and is associated with nearly 100% human mortality if left untreated. Y. pestis is susceptible to commonly available antibiotics if treatment begins soon after infection. However, depending on the route of infection, the time at which infection is confirmed is often too late for antibiotics to prevent significant morbidity or mortality.¹⁰ Because pneumonic plague is the form most likely to be seen in bioterrorism events,¹⁶ interest in animal models has arisen to support development of vaccines and improved therapeutics.Potential vaccines and therapeutic agents for plague must protect against the pneumonic disease, but contemporary published data regarding disease pathogenesis using aerosolized Y. pestis pathogenesis in nonhuman primates are scant.^4,9,21,23,24 In the United States, when vaccine or antibiotic efficacy cannot be evaluated in humans, an animal species that is reasonably expected to recapitulate human disease must be used.⁹ For many biothreat agents such as plague, a nonhuman primate model often is required. Although some laboratories have examined the cynomolgus macaque model of aerosolized plague briefly,¹ no published reports fully characterize this model. Published studies have examined plague in the African green monkey or vervet (Chlorocebus spp., formerly Cercopithecus aethiops) and rhesus macaque (Macaca mulatta).¹ Vervets reportedly are more sensitive to plague than are macaques,^4,24 such that some vervets are susceptible to infection with vaccine strains, casting some doubt on applicability of this species for plague studies.¹ The disease in rhesus macaques differs from that in humans in that rhesus macaques frequently develop disseminated intravascular coagulation (DIC) and chronic pneumonia as a result of pneumonic plague while humans usually develop acute pneumonia without DIC.^1,7Many participants at a recent symposium sponsored by the Food and Drug Administration and National Institute of Allergy and Infectious Disease endorsed the development of a cynomolgus macaque pneumonic plague model to support plague therapeutic and vaccine studies.⁸ The current study was undertaken to evaluate the Indonesian cynomolgus macaque as a model of aerosolized Y. pestis Colorado 92 (YpCO92) for subsequent vaccine and therapeutic trials. We also sought to determine whether fever development could be used to determine a humane endpoint to the study, as an alternative to LD₅₀ methods.     

Dynamics of Cytokine/Chemokine Responses in Intestinal CD4+ and CD8+ T Cells during Acute Simian Immunodeficiency Virus Infection

Loss of intestinal CD4⁺ T cells was associated with decreased production of several T-helper 1 (T_H1) and T_H2 cytokines and increased production of interleukin 17 (IL-17), gamma interferon (IFN-γ), CCL4, and granulocyte-macrophage colony-stimulating factor (GM-CSF) by CD8⁺ T cells 21 days after simian immunodeficiency virus (SIV) infection in rhesus macaques. Shifting of mucosal T_H1 to T_H2 or T-cytotoxic 1 (T_C1) to T_C2 cytokine profiles was not evident. Additionally, both CD4⁺ and CD8⁺ T cells showed upregulation of macrophage migration inhibition factor (MIF) and basic fibroblast growth factor (FGF-basic) cytokines that have been linked to HIV disease progression.     

HSV-2 infection of dendritic cells amplifies a highly susceptible HIV-1 cell target

Herpes simplex virus type 2 (HSV-2) increases the risk of HIV-1 infection and, although several reports describe the interaction between these two viruses, the exact mechanism for this increased susceptibility remains unclear. Dendritic cells (DCs) at the site of entry of HSV-2 and HIV-1 contribute to viral spread in the mucosa. Specialized DCs present in the gut-associated lymphoid tissues produce retinoic acid (RA), an important immunomodulator, able to influence HIV-1 replication and a key mediator of integrin α₄β₇ on lymphocytes. α₄β₇ can be engaged by HIV-1 on the cell-surface and CD4⁺ T cells expressing high levels of this integrin (α₄β₇ ^high) are particularly susceptible to HIV-1 infection. Herein we provide in-vivo data in macaques showing an increased percentage of α₄β₇ ^high CD4⁺ T cells in rectal mucosa, iliac lymph nodes and blood within 6 days of rectal exposure to live (n = 11), but not UV-treated (n = 8), HSV-2. We found that CD11c⁺ DCs are a major target of HSV-2 infection in in-vitro exposed PBMCs. We determined that immature monocyte-derived DCs (moDCs) express aldehyde dehydrogenase ALDH1A1, an enzyme essential for RA production, which increases upon HSV-2 infection. Moreover, HSV-2-infected moDCs significantly increase α₄β₇ expression on CD4⁺ T lymphocytes and HIV-1 infection in DC-T cell mixtures in a RA-dependent manner. Thus, we propose that HSV-2 modulates its microenviroment, influencing DC function, increasing RA production capability and amplifying a α₄β₇ ^highCD4⁺ T cells. These factors may play a role in increasing the susceptibility to HIV-1.     

Pathogenicity and mucosal transmissibility of the R5-tropic simian/human immunodeficiency virus SHIV(AD8) in rhesus macaques: implications for use in vaccine studies

There is an urgent need to develop new pathogenic R5 simian/human immunodeficiency viruses (SHIVs) for the evaluation of candidate anti-HIV vaccines in nonhuman primates. Here, we characterize swarm SHIV_AD8 stocks, prepared from three infected rhesus macaques with documented immunodeficiency at the time of euthanasia, for their capacity to establish durable infections in macaques following inoculation by the intravenous (i.v.) or intrarectal (i.r.) route. All three viral stocks (SHIV_AD8-CE8J, SHIV_AD8-CK15, and SHIV_AD8-CL98) exhibited robust replication in vivo and caused marked depletion of CD4⁺ T cells affecting both memory and naïve CD4⁺ T lymphocyte subsets following administration by either route. Eleven of 22 macaques inoculated with the new SHIV_AD8 stocks were euthanized with clinical symptoms of immunodeficiency and evidence of opportunistic infections (Pneumocystis, Candida, and Mycobacterium). A single but unique founder virus, also present in the SHIV_AD8-CE8J swarm stock, was transmitted to two animals following a single i.r. inoculation of approximately 3 50% animal infectious doses, which is close to the threshold required to establish infection in all exposed animals. Because the three new SHIV_AD8 viruses are mucosally transmissible, exhibited tier 2 sensitivity to anti-HIV-1 neutralizing antibodies, deplete CD4⁺ T lymphocytes in vivo, and induce AIDS in macaques, they are eminently suitable as challenge viruses in vaccine experiments.     

Laparoscopic ovarian transposition before pelvic radiation in rectal cancer patient: safety and feasibility

Background

Infertility due to pelvic radiation for advanced rectal cancer treatment is a major concern particularly in young patients. Pre-radiation laparoscopic ovarian transposition may offer preservation of ovarian function during the treatment however its use is limited.

Aim

The study investigates the safety, feasibility and effectiveness of pre-radiation laparoscopic ovarian transposition and its effect on ovarian function in the treatment o locally advanced rectal cancer.

Methods

Charts review of all young female patients diagnosed with locally advanced rectal cancer, underwent laparoscopic ovarian transposition, then received preoperative radiotherapy at king Faisal Specialist Hospital and Research Centre between 2003?C2007.

Results

During the period studied three single patients age between 21?C27?years underwent pre-radiation laparoscopic ovarian transposition for advanced rectal cancer. All required pretreatment laparoscopic diversion stoma due to rectal stricture secondary to tumor that was performed at the same time. One patient died of metastatic disease during treatment. The ovarian hormonal levels (FSH and LH) were normal in two patients. One has had normal menstrual period and other had amenorrhoea after 4?months follow-up however her ovarian hormonal level were within normal limits.

Conclusions

Laparoscopic ovarian transposition before pelvic radiation in advanced rectal cancer treatment is an effective and feasible way of preservation of ovarian function in young patients at risk of radiotherapy induced ovarian failure. However, this procedure is still under used and it is advisable to discuss and propose it to suitable patients.