1
|
Thomas JA, Gireesh Moly AG, Xavier H, Suboj P, Ladha A, Gupta G, Singh SK, Palit P, Babykutty S. Enhancement of immune surveillance in breast cancer by targeting hypoxic tumor endothelium: Can it be an immunological switch point? Front Oncol 2023; 13:1063051. [PMID: 37056346 PMCID: PMC10088512 DOI: 10.3389/fonc.2023.1063051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 02/17/2023] [Indexed: 03/30/2023] Open
Abstract
Breast cancer ranks second among the causes of cancer-related deaths in women. In spite of the recent advances achieved in the diagnosis and treatment of breast cancer, further study is required to overcome the risk of cancer resistance to treatment and thereby improve the prognosis of individuals with advanced-stage breast cancer. The existence of a hypoxic microenvironment is a well-known event in the development of mutagenesis and rapid proliferation of cancer cells. Tumor cells, purposefully cause local hypoxia in order to induce angiogenesis and growth factors that promote tumor growth and metastatic characteristics, while healthy tissue surrounding the tumor suffers damage or mutate. It has been found that these settings with low oxygen levels cause immunosuppression and a lack of immune surveillance by reducing the activation and recruitment of tumor infiltrating leukocytes (TILs). The immune system is further suppressed by hypoxic tumor endothelium through a variety of ways, which creates an immunosuppressive milieu in the tumor microenvironment. Non responsiveness of tumor endothelium to inflammatory signals or endothelial anergy exclude effector T cells from the tumor milieu. Expression of endothelial specific antigens and immunoinhibitory molecules like Programmed death ligand 1,2 (PDL-1, 2) and T cell immunoglobulin and mucin-domain containing-3 (TIM-3) by tumor endothelium adds fuel to the fire by inhibiting T lymphocytes while promoting regulatory T cells. The hypoxic microenvironment in turn recruits Myeloid Derived Suppressor Cells (MDSCs), Tumor Associated Macrophages (TAMs) and T regulatory cells (Treg). The structure and function of newly generated blood vessels within tumors, on the other hand, are aberrant, lacking the specific organization of normal tissue vasculature. Vascular normalisation may work for a variety of tumour types and show to be an advantageous complement to immunotherapy for improving tumour access. By enhancing immune response in the hypoxic tumor microenvironment, via immune-herbal therapeutic and immune-nutraceuticals based approaches that leverage immunological evasion of tumor, will be briefly reviewed in this article. Whether these tactics may be the game changer for emerging immunological switch point to attenuate the breast cancer growth and prevent metastatic cell division, is the key concern of the current study.
Collapse
Affiliation(s)
- Juvin Ann Thomas
- Centre for Tumor Immunology and Microenvironment, Department of Zoology, Mar Ivanios College, Nalanchira, Thiruvananthapuram, Kerala, India
| | - Athira Gireesh Gireesh Moly
- Centre for Tumor Immunology and Microenvironment, Department of Zoology, Mar Ivanios College, Nalanchira, Thiruvananthapuram, Kerala, India
| | - Hima Xavier
- Centre for Tumor Immunology and Microenvironment, Department of Zoology, Mar Ivanios College, Nalanchira, Thiruvananthapuram, Kerala, India
| | - Priya Suboj
- Department of Botany and Biotechnology, St. Xaviers College, Thumba, Thiruvananthapuram, Kerala, India
| | - Amit Ladha
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, West-Midlands, United Kingdom
| | - Gaurav Gupta
- Department of Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - Santosh Kumar Singh
- Centre of Experimental Medicine and Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Partha Palit
- Drug Discovery Research Laboratory, Assam University, Silchar, Department of Pharmaceutical Sciences, Assam, India
| | - Suboj Babykutty
- Centre for Tumor Immunology and Microenvironment, Department of Zoology, Mar Ivanios College, Nalanchira, Thiruvananthapuram, Kerala, India
| |
Collapse
|
2
|
Kumar A, Ladha A, Choudhury A, Ikbal AMA, Bhattacharjee B, Das T, Gupta G, Sharma C, Sarbajna A, Mandal SC, Choudhury MD, Ali N, Slama P, Rezaei N, Palit P, Tiwari ON. The chimera of S1 and N proteins of SARS-CoV-2: can it be a potential vaccine candidate for COVID-19? Expert Rev Vaccines 2022; 21:1071-1086. [PMID: 35604776 DOI: 10.1080/14760584.2022.2081156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as one of the biggest global health issues. Spike protein (S) and nucleoprotein (N), the major immunogenic components of SARS-CoV-2, have been shown to be involved in the attachment and replication of the virus inside the host cell. AREAS COVERED Several investigations have shown that the SARS-CoV-2 nucleoprotein can elicit a cell-mediated immune response capable of regulating viral replication and lowering viral burden. However, the development of an effective vaccine that can stop the transmission of SARS-CoV-2 remains a matter of concern. Literature was retrieved using the keywords COVID-19 vaccine, role of nucleoprotein as vaccine candidate, spike protein, nucleoprotein immune responses against SARS-CoV-2, and chimera vaccine in PubMed, Google Scholar, and Google. EXPERT OPINION We have focussed on the use of chimera protein, consisting of N and S-1 protein components of SARS-CoV-2, as a potential vaccine candidate. This may act as a polyvalent mixed recombinant protein vaccine to elicit a strong T and B cell immune response, which will be capable of neutralizing the wild and mutated variants of SARS-CoV-2, and also restricting its attachment, replication, and budding in the host cell.
Collapse
Affiliation(s)
- Amresh Kumar
- Department of Life Sciences and Bioinformatics, Assam University, Silchar, India
| | - Amit Ladha
- Area of Biotechnology and Bioinformatics, NIIT University, Neemrana, India
| | - Ankita Choudhury
- Department of Pharmaceutical Sciences, Allama TR College of Pharmacy, Hospital Rd, Srigouri, India
| | - Abu Md Ashif Ikbal
- Department of Pharmacy, Tripura University (A Central University), Suryamaninagar, Tripura (W), India
| | - Bedanta Bhattacharjee
- Department of Pharmaceutical Sciences, Faculty of Science and Engineering, Dibrugarh University, Dibrugarh, India
| | - Tanmay Das
- Department of Business Administration, Assam University Silchar, India
| | - Gaurav Gupta
- Area of Biotechnology and Bioinformatics, NIIT University, Neemrana, India.,Department of Immunology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Chhavi Sharma
- Area of Biotechnology and Bioinformatics, NIIT University, Neemrana, India
| | - Adity Sarbajna
- Department of Zoology, Surendranath College, Kolkata, India
| | - Subhash C Mandal
- Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India
| | | | - Nahid Ali
- Division of Immunology, Department of Infectious Diseases, INDIAN INSTITUTE OF CHEMICAL BIOLOGY, Kolkata, India
| | - Petr Slama
- Laboratory of Animal Immunology and Biotechnology, Department of Animal Morphology, Physiology and Genetics, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, Brno, Czech Republic
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran.,Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Stockholm, Sweden
| | - Partha Palit
- Department of Pharmaceutical Sciences Drug Discovery research Laboratory, Assam University, Silchar, India
| | - Onkar Nath Tiwari
- Centre for Conservation and Utilisation of Blue Green Algae (CCUBGA), Division of Microbiology, ICAR-Indian Agricultural Research Institute (IARI), New Delhi, India
| |
Collapse
|
3
|
Ladha A, Garg P, Puranik C. A simplified easily reproducible pudendal nerve block technique for anorectal surgery (SEPTA) - a video vignette. Colorectal Dis 2018; 20:829. [PMID: 29770547 DOI: 10.1111/codi.14261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 04/23/2018] [Indexed: 02/08/2023]
Affiliation(s)
- A Ladha
- Vishesh Hospital, Indore, Madhya Pradesh, India
| | - P Garg
- Garg Fistula Research Institute, Panchkula, Haryana, India.,Indus Super Speciality Hospital, Mohali, India
| | - C Puranik
- Vishesh Hospital, Indore, Madhya Pradesh, India
| |
Collapse
|
4
|
Ladha A, Alam A, Idestrup C, Sawyer J, Choi S. Spinal haematoma after removal of a thoracic epidural catheter in a patient with coagulopathy resulting from unexpected vitamin K deficiency. Anaesthesia 2013; 68:856-60. [DOI: 10.1111/anae.12285] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2013] [Indexed: 12/18/2022]
Affiliation(s)
- A. Ladha
- Department of Anesthesia; University of Toronto; Toronto; Canada
| | - A. Alam
- Department of Anesthesia and Pain Medicine; The Hospital for Sick Children and Department of Laboratory Medicine and Pathobiology; University of Toronto; Toronto; Canada
| | - C. Idestrup
- Department of Anesthesia; Sunnybrook Health Sciences Centre; University of Toronto; Toronto; Canada
| | - J. Sawyer
- Acute Pain Service; Sunnybrook Health Sciences Centre and Adjunct Lecturer; Lawrence Bloomberg Faculty of Nursing; University of Toronto; Toronto; Canada
| | - S. Choi
- Department of Anesthesia; Sunnybrook Health Sciences Centre; University of Toronto; Toronto; Canada
| |
Collapse
|
5
|
Namias N, Harvill S, Ball S, McKenney MG, Sleeman D, Ladha A, Civetta J. A reappraisal of the role of Gram's stains of tracheal aspirates in guiding antibiotic selection in the surgical intensive care unit. J Trauma 1998; 44:102-6. [PMID: 9464756 DOI: 10.1097/00005373-199801000-00012] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Tracheal aspirate Gram's stains are used to guide antibiotic selection in empiric pneumonia treatment in the surgical intensive care unit (SICU). We questioned whether Gram's stains predict the organism cultured. METHODS A retrospective review of prospectively collected data. RESULTS Gram's stains correlated with the cultured organism in 284 of 543 (52%) SICU cultures and in 226 of 403 (56%) trauma intensive care unit (TICU) cultures. Gram-negative rod (GNR) stains yielded GNR organisms in 182 of 205 (89%) SICU cultures and in 160 of 176 (91%) TICU cultures. Gram-positive coccus (GPC) stains yielded GPC organisms in 75 of 228 (33%) SICU cultures and in 52 of 149 (35%) TICU cultures. Noncorrelates in the GPC group were predominantly GNRs (185 of 250 (74%)). CONCLUSION When the clinical decision has been made that empiric antibiotic coverage is necessary, GNR coverage should be instituted regardless of Gram's stain result. The decision to institute GPC coverage needs to be supported by clinical data other than the Gram's stain.
Collapse
Affiliation(s)
- N Namias
- Emory University School of Medicine, Atlanta, Georgia 30303, USA
| | | | | | | | | | | | | |
Collapse
|
6
|
Lee-Ruff E, Ostrowski M, Ladha A, Stynes DV, Vernik I, Jiang JL, Wan WQ, Ding SF, Joshi S. Synthesis and HIV inhibition activity of 2',3'-dideoxy-3'-C-hydroxymethyl nucleosides. J Med Chem 1996; 39:5276-80. [PMID: 8978856 DOI: 10.1021/jm950822k] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A series if 2',3'-dideoxy-3'-C-hydroxymethyl purine nucleosides were prepared based on the photochemical ring expansion of a chiral cyclobutanone precursor, (2S)-trans-2,3-bis[(benzoyloxy)methyl]cyclobutanone, in the presence of a 6-substituted purine. Both alpha- and beta-anomers are produced in this transformation. Deprotection was effected by reaction of the photoadducts with saturated methanolic ammonia. Nine purine nucleosides were tested for their inhibitory effect of HIV IIIB virus on H9 cells. The 6-hexyloxy and adenine derivatives 4e,c, respectively, appeared to be most effective at inhibiting viral reproduction with 4c comparable in activity to ddI and AZT.
Collapse
Affiliation(s)
- E Lee-Ruff
- Department of Chemistry, York University, Toronto, Ontario, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Soyannwo MA, Khan N, Kommajosyula S, Abdel Rahman AR, Khadaji M, Sing R, Laithy SU, Ladha A, Azzam A, Desmukh S. Hepatitis C antibodies in haemodialysis and pattern of end-stage renal failure in Gassim, Saudi Arabia. Afr J Med Med Sci 1996; 25:13-22. [PMID: 9110050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
As by the end of 1992, 96 (47 females; 49 females) patients were on regular dialysis treatment for end stage renal failure (ESRF) in 5 haemodialysis HD units, the Gassim region of Saudi Arabia. Because of lack of facilities, paediatric patients were under-represented, age range being 11 to 80 years. Systemic hypertension (47%), followed by hereditary/congenital conditions (23%) and non-insulin dependent diabetes mellitus NIDDM (19%) were the most common causes of ESRF in the region. One patients developed ESRF 14 years after donor nephrectomy. Overall prevalence of HCAb was 50% with a range of 17.24% to 83%. Based, especially, on the findings in two of the units which between them handle 57% (55/96) of the patients, we believe that the practice of machine isolation policy (MIP) rather than blood transfusion is largely responsible for this wide variation in prevalence between the centres. Considering the very high overall prevalence of the Kingdom, we suggest the MIP should no longer be optional and should be part of the universal infection precautions for HD patients. Comparing Gassim with findings from Taif, there may be some variation in the pattern of ESRF between different parts of the Kingdom. More reports will be needed to document this. Donor nephrectomy as a cause of ESRF is being recorded for the first time in the Kingdom. Vigilance is important. Similarly, we believe that sexual intercourse as a probable route of hepatitis C virus HCV transmission is being recorded for the first time in the Kingdom.
Collapse
Affiliation(s)
- M A Soyannwo
- Nephrology unit, King Fahd specialist hospital, Buraidah, Gasim, Saudi Arabia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Ladha A. Effect of refrigeration on Mantoux test result. Indian Pediatr 1995; 32:1036-5. [PMID: 8935274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|
9
|
Friborg J, Ladha A, Göttlinger H, Haseltine WA, Cohen EA. Functional analysis of the phosphorylation sites on the human immunodeficiency virus type 1 Vpu protein. J Acquir Immune Defic Syndr Hum Retrovirol 1995; 8:10-22. [PMID: 8548340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The human immunodeficiency virus type 1 (HIV-1)-encoded vpu product is a small class 1 integral membrane protein that is phosphorylated by the ubiquitous casein kinase II (CKII) in HIV-1-infected cells. The Vpu protein facilitates the release of budding virions from the surface of infected cells and delays the rate of syncytium formation. In this study, we investigated the role of phosphorylation in the biological activity of Vpu. Our results show that phosphorylation of Vpu occurs on serine residues at positions 52 and 56 located in a highly conserved dodecapeptide sequence. Mutation of either Ser 56, or both Ser 52 and Ser 56 impaired the ability of Vpu to delay the rate of syncytium formation while retaining virion release activity at levels comparable to vpu+ proviruses. Flow cytometry analysis indicates that the relative amounts of envelope glycoprotein gp120 expressed at the surface of cells transfected with these vpu mutant proviruses was two- to threefold greater than that observed on cells transfected with a vpu+ provirus. This increased expression of gp120 at the cell surface may explain the more rapid onset of syncytium formation observed in cell transfected with vpu mutant proviruses. These results suggest that Vpu-facilitated virion release and delayed cytopathic effect are the consequence of two distinct functional activities of the protein.
Collapse
Affiliation(s)
- J Friborg
- Département de Microbiologie et Immunologie, Faculté de Médecine, Université de Montréal, Québec, Canada
| | | | | | | | | |
Collapse
|
10
|
Lavallée C, Yao XJ, Ladha A, Göttlinger H, Haseltine WA, Cohen EA. Requirement of the Pr55gag precursor for incorporation of the Vpr product into human immunodeficiency virus type 1 viral particles. J Virol 1994; 68:1926-34. [PMID: 8107252 PMCID: PMC236654 DOI: 10.1128/jvi.68.3.1926-1934.1994] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) particles consists of two molecules of genomic RNA as well as molecules originating from gag, pol, and env products, all synthesized as precursor proteins. The 96-amino-acid Vpr protein, the only virion-associated HIV-1 regulatory protein, is not part of the virus polyprotein precursors, and its incorporation into virus particles must occur by way of an interaction with a component normally found in virions. To investigate the mechanism of incorporation of Vpr into the HIV-1 virion, Vpr- proviral DNA constructs harboring mutations or deletions in specific virion-associated gene products were cotransfected with Vpr expressor plasmids in COS cells. Virus released from the transfected cells was tested for the presence of Vpr by immunoprecipitation with Vpr-specific antibodies. The results of these experiments show that Vpr is trans-incorporated into virions but at a lower efficiency than when Vpr is expressed from a proviral construct. The minimal viral genetic information necessary for Vpr incorporation was a deleted provirus encoding only the pr55gag polyprotein precursor. Incorporation of Vpr requires the expression but not the processing of gag products and is independent of pol and env expression. Direct interaction of Vpr with the Pr55gag precursor protein was demonstrated by coprecipitation experiments with gag product-specific antibodies. Overall, these results indicate that HIV-1 Vpr is incorporated into the nascent virion through an interaction with the Gag precursor polyprotein and demonstrate a novel mechanism by which viral protein can be incorporated into virus particles.
Collapse
Affiliation(s)
- C Lavallée
- Département de Microbiologie et Immunologie, Faculté de Médecine, Université de Montréal, Quebec, Canada
| | | | | | | | | | | |
Collapse
|
11
|
Jiang M, Mak J, Ladha A, Cohen E, Klein M, Rovinski B, Kleiman L. Identification of tRNAs incorporated into wild-type and mutant human immunodeficiency virus type 1. J Virol 1993; 67:3246-53. [PMID: 8497049 PMCID: PMC237665 DOI: 10.1128/jvi.67.6.3246-3253.1993] [Citation(s) in RCA: 171] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have identified the tRNAs which are incorporated into both wild-type human immunodeficiency virus type 1 strain IIIB (HIV-1IIIB) produced in COS-7 cells transfected with HIV-1 proviral DNA and mutant, noninfectious HIV-1Lai particles produced in a genetically engineered Vero cell line. The mutant proviral DNA contains nucleotides 678 to 8944; i.e., both long terminal repeats and the primer binding site are absent. As analyzed by two-dimensional polyacrylamide gel electrophoresis, both mutant and wild-type HIV-1 contain four major-abundance tRNA species, which include tRNA(1,2Lys), tRNA(3Lys) (the putative primer for HIV-1 reverse transcriptase) and tRNA(Ile). Identification was accomplished by comparing the electrophoretic mobilities and RNase T1 digests with those of tRNA(3Lys) and tRNA(1,2Lys) purified from human placenta and comparing the partial nucleotide sequence at the 3' end of each viral tRNA species with published tRNA sequences. Thus, the absence of the primer binding site in the mutant virus does not affect tRNA(Lys) incorporation into HIV-1. However, only the wild-type virus contains tRNA(3Lys) tightly associated with the viral RNA genome. The identification of the tightly associated tRNA as tRNA(3Lys) is based upon an electrophoretic mobility identical to that of tRNA(3Lys) and the ability of this RNA to hybridize with a tRNA(3Lys)-specific DNA probe. In addition to the four wild-type tRNA species, the mutant HIV-1-like particle contains two tRNA(His) species and three tRNA-sized species that we have been unable to identify. Their absence in wild-type virus makes it unlikely that they are required for viral infectivity.
Collapse
MESH Headings
- Acquired Immunodeficiency Syndrome/genetics
- Acquired Immunodeficiency Syndrome/metabolism
- Animals
- Base Sequence
- Genome, Viral
- HIV-1/genetics
- HIV-1/growth & development
- Humans
- Molecular Sequence Data
- Mutation
- RNA, Transfer/genetics
- RNA, Transfer/metabolism
- RNA, Transfer, Lys/genetics
- RNA, Transfer, Lys/metabolism
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Repetitive Sequences, Nucleic Acid/genetics
- Ribonuclease T1/metabolism
- Sequence Analysis, RNA
Collapse
Affiliation(s)
- M Jiang
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Montreal, Quebec, Canada
| | | | | | | | | | | | | |
Collapse
|
12
|
Ahmad A, Ladha A, Cohen EA, Menezes J. Stable expression of the transfected HIV-1 env gene in a human B cell line: characterization of gp120-expressing clones and immunobiological studies. Virology 1993; 192:447-57. [PMID: 8421893 DOI: 10.1006/viro.1993.1060] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The env gene of human immunodeficiency virus type 1 (HIV-1) encodes gp 120/41 which plays an important role in the viral infection process and pathogenesis. The surface glycoprotein gp120 is a candidate molecule for the development of a subunit vaccine against HIV-1-induced acquired immunodeficiency syndrome (AIDS). However, thorough studies on the immunobiology of this molecule are hampered by the lack of a suitable model. With this background in mind, and in order to learn more on anti-gp120 cellular immunity, we attempted to develop gp120-expressing human cell clones. Thus by transfecting a human lymphoid cell line of B lineage (Raji), which is known to be resistant to the natural killer cell activity, with an expression vector encoding the envelope and vpu, we established three clones that stably express gp120/41 and vpu. The surface glycoprotein gp 120 is also expressed on the cell surface of these clones. The transfected cells from syncytia with CD4+ human cell lines as well as with peripheral blood mononuclear cells (PBMC) leading to the death of the fused cells. This observation represents additional evidence for the eventual depletion of CD4+ viral targets that fuse with adjacent HIV-infected, gp 120-expressing cells. The latent Epstein-Barr virus genome present in the transfected cells, was not induced to express the lytic cycle antigens. The densities of the surface expression of a number of molecules examined remained unchanged in the transfected cells except for the surface IgM, which increased significantly (P < 0.05) in two clones. One of the clones exhibited a significantly (P < 0.05) reduced proliferation rate as compared to the other clones. The transfected cells of all the three clones showed a significantly (P < 0.01) increased susceptibility to lysis by the PBMC from normal, healthy individuals in a 16-hr 51Cr-release assay. This is the first report of the MHC- and antibody-independent lysis of human cells transfected with the HIV-1 surface glycoprotein. The transfected cells also served as targets in a gp120-specific antibody-dependent cellular cytotoxicity assay. We anticipate that the present model will prove very useful for studying the gp120-specific immune responses in HIV-infected individuals.
Collapse
Affiliation(s)
- A Ahmad
- Laboratory of Immunovirology, Sainte-Justine Hospital, Montreal, Qc., Canada
| | | | | | | |
Collapse
|
13
|
Abstract
A modification of the technique suggested by Hopkinson for the repair of rectal prolapse via the perineal route is described. This technique involves the use of an Angelchik Anti-Reflux Prosthesis and is particularly suitable for elderly patients in whom abdominal rectopexy would be hazardous because of general health.
Collapse
|