Genetically Modified Hematopoietic Stem Cell Transplantation for HIV-1–infected Patients: Can We Achieve a Cure?

The cure of a human immunodeficiency virus (HIV)-1–infected patient following allogeneic transplantation from a CCR5-null donor and potential cure of two patients transplanted with CCR5 wild-type hematopoietic stem cells (HSC) have provided renewed optimism that a potential alternative to conventional antiretroviral therapy (ART) is forthcoming. While allogeneic grafts have thus far suggested complete eradication of viral reservoirs, it has yet to be observed following autologous HSC transplantation. Development of curative autologous transplantation strategies would significantly increase the number of treatable patients, eliminating the need for matched donors and reducing the risks of adverse events. Recent studies suggest gene therapy may provide a mechanism for developing curative therapies. Expression of cellular/artificial restriction factors or disruption of CCR5 has been shown to limit viral replication and provide protection of genetically modified cells. However, significant obstacles remain with regards to the depletion of established viral reservoirs in an autologous transplantation setting devoid of the “allo-effect”. Here, we discuss results from early-stage clinical trials and recent findings in animal models of gene modified HSC transplantation. Finally, we propose innovative combination therapies that may aid in the reduction and/or elimination of viral reservoirs in HIV-1–infected patients and promote the artificial development of a natural controller phenotype.Gene therapy approaches have recently come to the forefront of alternative methods in the quest for the development of curative strategies for the treatment of human immunodeficiency virus (HIV)-1–infected patients. Nearly all of these studies have been aimed at developing infection-resistant immune cell populations highlighting the findings published by Hütter et al., in which a single HIV-1–infected patient, known as the “Berlin patient”, was effectively cured of HIV following allogeneic hematopoietic stem cell transplantation (HSCT) from a CCR5-null donor.¹ While several questions remain concerning what aspects of treatment or if multiple interventions led to the cure of this patient, a new role for gene therapy in the pursuit of a cure for HIV/acquired immunodeficiency syndrome has emerged.Although current antiretroviral therapy (ART) is perhaps one of the most vital breakthroughs in the modern era of medicine, this therapy does not equate a cure. Strategies to genetically modify target cells have evolved over the last two decades; however, for the most part, the underlying theme of preventing the expression of cellular factors needed for viral infection and/or the expression of restrictive factors has remained relatively unchanged (see ref. ² for review of previously characterized methods for developing infection-resistant cells). Few approaches aimed at targeting proviral DNA have been developed; however, recent breakthroughs in genetic engineering of sequence specific nucleases may pave the way for future targeted therapies aimed at reducing viral reservoirs (reviewed in ref. ³). This review discusses the early-stage clinical findings, the current progress made in preclinical animal models, the ambitious goals needed to achieve a functional cure with relation to findings in elite controllers, and the innovative therapies that may be needed to eliminate or reduce viral reservoirs in combination with autologous, gene modified HSCT. Here, a “functional cure” is defined as conditions that lead to the complete and sustainable control of plasma viremia at levels that are currently achievable by conventional highly active ART (HAART). We refer to “eradication” as a sterilizing cure in which no replication competent forms of HIV exist.     

Rescue therapy with tacrolimus in a patient with toxic megacolon

BACKGROUND: Toxic megacolon is a life-threatening complication most commonly observed in patients with ulcerative colitis or Crohn's disease that is characterized by total or segmental nonobstructive colonic dilatation of at least 6 cm on plain abdominal films associated with systemic toxicity. CASE REPORT: We report an unusual case of fulminant steroid-refractory ulcerative colitis complicated by toxic megacolon treated successfully with the immunosuppressant tacrolimus. CONCLUSION: Tacrolimus administration induced clinical remission and bridged the time interval, until the standard immunosuppressant azathioprine could maintain clinical remission, thereby avoiding eminent emergency colectomy.     

Molecular genotyping in a malaria treatment trial in Uganda - unexpected high rate of new infections within 2 weeks after treatment

Polymerase chain reaction (PCR) genotyping of malaria parasites in drug efficacy trials helps differentiate reinfections from recrudescences. A combination therapy trial of one (n = 115) or three (n = 117) days artesunate (1AS, 3AS 4 mg/kg/day) plus sulphadoxine-pyrimethamine (SP) vs. SP alone (n = 153) was conducted in Mbarara, a mesoendemic area of western Uganda. All paired recurrent Plasmodium falciparum parasitaemias on days 7, 14, 21 and 28 post-treatment were genotyped by PCR amplification and analysis of glutamate-rich protein (glurp) and merozoite surface proteins (msp) 1 and 2 genes to distinguish recrudescent from new infections. A total of 156 (1AS = 61, 3AS = 35, SP alone = 60) of 199 paired recurrent samples were successfully analysed and were resolved as 79 recrudescences (1AS = 32, 3AS = 8, SP = 39) and 77 as new infections (1AS = 29, 3AS = 27, SP = 21). The ratios of proportions of new to recrudescent infections were 0.2, 0.9, 1.4 and 1.9 on days 7, 14, 21 and 28, respectively (P < 0.001, chi(2) test for linear trend). Unexpected high new infection rates were observed early in follow-up on days 7 [5/26 (19.2%)] and 14 [24/51 (47.1%)]. These results impact significantly on resistance monitoring and point to the value of genotyping all recurrent infections in antimalarial trials.     

Immune response to capsular polysaccharide and surface proteins of Streptococcus pneumoniae in patients with invasive pneumococcal disease

The immune response to pneumococcal capsular polysaccharides (CPSs) and to the pneumococcal surface proteins cell wall-associated serine proteinase A (PrtA), pneumococcal surface protein A (PspA), and Streptococcus pneumoniae pullulanase A was evaluated in 45 patients with invasive pneumococcal disease compared with healthy adults. In serum from patients with meningitis and pneumonia, CPS antibody levels were low, compared with healthy adults; antibody levels did not differ between groups and did not change between phases. Levels of immunoglobulin G directed against the investigated pneumococcal surface proteins in patients with invasive pneumococcal disease were in the same range as in healthy adults. However, median PrtA and PspA antibody levels tended to increase during early convalescent phase. Low levels of CPS antibody, rather than of antibodies directed against the pneumococcal surface proteins, may predispose to invasive pneumococcal infection.     

Transition from primary Raynaud's phenomenon to secondary Raynaud's phenomenon identified by diagnosis of an associated disease: results of ten years of prospective surveillance

OBJECTIVE: To assess the early signs, risk factors, and rate of transition from primary Raynaud's phenomenon (primary RP) to secondary RP. METHODS: A clinical sample of 307 consecutive patients with RP was included in a prospective followup study. After an initial screening, 244 patients were classified as having primary RP, of whom 236 were followed up for a mean +/- SD of 11.2 +/- 3.9 years. Patients classified according to the screening as having suspected secondary RP underwent an extended screening program annually until transition to secondary RP occurred. RESULTS: The initial prevalence of secondary RP was 11%. The annual incidence of transition to suspected secondary RP was 2%, and the annual incidence of transition to secondary RP was 1%. Overall, 46 patients were classified as having suspected secondary RP, and 23 of these later were classified as having secondary RP. Older age at onset of RP (hazard ratio 2.59, 95% confidence interval [95% CI] 1.40-4.80), shorter duration of RP at enrollment (hazard ratio 0.87, 95% CI 0.81-0.94), and abnormal findings on thoracic outlet test (hazard ratio 2.69, 95% CI 1.12-6.48) were associated with an increased risk for transition to secondary RP. Compared with patients with suspected secondary RP, those diagnosed as having secondary RP had a higher number and earlier occurrence of pathologic findings. Furthermore, antinuclear antibodies at a titer of > or = 1:320 and positive findings in specific serologic subsets were associated with a significantly increased risk for developing a connective tissue disease. CONCLUSION: Patients diagnosed initially as having primary RP may actually comprise 1 of 3 groups: those with idiopathic RP, those with a rather benign disease course, and those with a more severe course of the disease.     

Komplizierte Divertikulitis

ZusammenfassungHintergrund: Die Sigmadivertikulitis nimmt in 10–20% einen komplizierten Verlauf, der der chirurgischen Therapie bedarf. Neben freier Perforation, Abszess und Blutung sind Fisteln eine Indikation. Vergleichsweise selten handelt es sich dabei um sigmoidovaginale Fisteln.Methodik: Der Stellenwert der Laparoskopie bei komplizierter Divertikulitis ist kontrovers. Sie kann jedoch ein sicheres und effektives Operationsverfahren darstellen. Anhand der verfügbaren Literatur greifen die Autoren gezielt die Erfahrungen mit der minimalinvasiven Chirurgie (MIC) bei sigmoidovaginaler Fistel auf und präsentieren mit drei Fallbeispielen ein eigenes Therapiekonzept. Hierbei werden die laparoskopische Sigmaresektion und primäre Anastomosierung um eine intraabdominelle Naht der Scheide sowie plastische Deckung mittels Netzplombe ergänzt.Ergebnisse: Alle Operationen wurden laparoskopisch vollendet. Die mittlere Operationsdauer betrug 243 Minuten. Hinsichtlich der Morbidität (1 Majorkomplikation, 1 Minorkomplikation) und Letalität (0) stand der postoperative Verlauf in guter Übereinstimmung mit der Literatur. Der Kostaufbau beanspruchte im Mittel 1,7 Tage (flüssige Kost) bzw. 6,3 Tage (feste Kost), die Aufenthaltsdauer 13 Tage. Fistelrezidive traten während der 30-tägigen Nachbeobachtung nicht auf.Schlussfolgerung: Die Ergebnisse bestätigen den Stellenwert der Laparoskopie als operatives Standardverfahren bei komplizierter Divertikulitis an der eigenen Klinik.     

Endosonography of pararectal lymph nodes

One hundred thirteen patients with carcinoma of the rectum were evaluated for lymph node metastases by endorectal ultrasound. With the use of 7.5 MHz and based on different echo patterns, two main groups of lymph nodes can be differentiated: hypoechoic and hyperechoic lymph nodes. Compared with pathologic findings, hypoechoic lymph nodes represent metastases, whereas hyperechoic lymph nodes are visualized due to unspecific inflammation. Lymph node metastases can be predicted with a sensitivity of 72 percent and inflammatory lymph nodes with a specificity of 83 percent. The physical basis of the differentiation of lymph nodes was assessed in vitro by the determination of ultrasound parameters (speed of sound, acoustic impedance, attenuation, and backscattered amplitude). The attenuation coefficient of benign lymph nodes [2.5 dB/(MHz×cm)] is significantly higher than the mean value of lymph node metastases [1.3 db/(MHz×cm)]. The results demonstrate that involved nodes can principally be differentiated from not involved nodes. Micrometastases, mixed lymph nodes, and changing echo patterns within inflammatory nodes explain the accuracy rate of 78 percent.Supported by a grant from the Deutsche Forschungsgemeinschaft Hi 385/1-1