AIDS: An Explosion of the Biological Time-bomb?
CHAPTER ONE: Historic Interest in Latent/Persistent Infections
1930-1945
Scientific interest in acquired diseases and immunodeficiency is not new and, though the Acquired Immunodeficiency Syndrome (AIDS) made official entry into the annals of medicine in 1981 and was haled as an unprecedented phenomenon, investigation of acquired immunodeficiencies has an extensive history [1]. Early interest in agents associated with capacity to initiate immunologic disturbances can be traced back to the avian (bird) sarcoma-related viruses which, prior to the advent of World War I, were subjects of study by both American and German scientists. Sarcoma is a fleshy, tumor of connective tissue, usually highly malignant, formed by excessive proliferation of tissue which had its primitive origin in the middle of the three primary germ layers of the developing embryo. Called the "mesoderm," this embryonic tissue gives eventual origin to all connective tissues, all body musculature, blood, cardiovascular and lymphatic systems, most of the urogenital system, and the lining of the body's major cavities.
Rous (1911) worked with a transmissible agent derived from chicken tumor cells [2] and this chicken tumor agent later came to be known as "Rous sarcoma" in honor of its originator. Before World War II began, Rous's chicken tumor agent was intensively investigated and discovered related to erythroblastosis, i.e., a hemolytic anemia not unlike the Rh-factor disease of newborns which is technically known as "erythroblastosis -fetalis," and to myelosis, i.e., a condition of abnormal proliferation of bone marrow-related cells and tissue that is often characterized by anemia, irregular fever, swelling of the spleen and liver, hemorrhagic disorders and fewer red blood cells circulating in the blood [3]. In short, infection by Rous's tumor agent would induce contagious forms of anemia and leukemia.
Claude (1936) investigated effects of enzymes on this transmissible avian sarcoma [4] and Keogh (1938) confirmed that Rous sarcoma would induce ectodermal lesions (i.e., pathologic change in tissue which has its primitive origin in the outer layer of cells in the embryo and from which eventually evolves the brain, spinal cord, nerves, sense organs, and skin, e.g., epithelial/mucous membranes and cutaneous tissue) in infected hosts [5]. Kabat (1939) demonstrated that the Rous sarcoma/leukemia virus produced enzymatic effects in infected cells [6] and thus, by the advent of World War II, a transmissible leukemia/sarcoma-causing virus was nearly hypothetically available as a biological weapon. Preventing its immediate consideration as a potential biological weapon at the start of the War, its transmission was restricted to only fowls. This restriction, known as "virus-species specificity" would, however, not long prove to be a major barrier in the march of science.
Kaposi's sarcoma, now seen in many cases of AIDS, has existed since its original characterization by Kaposi in the 19th century. Review of medical literature on Kaposi's sarcoma presented in the 1930s indicates a growing interest in Kaposi’s disease symptoms among minorities. Pardo-Castello (1931) reported appearance of a case in a black individual [7] and another was reported by Andrews (1932) [8]. In 1934, a case of Kaposi's sarcoma was reported in an American black [9]. Though these cases of Kaposi's sarcoma were extremely rare it is important to point out that the disease did exist prior to advent of World War II. As Rous sarcoma was investigated regarding its leukemia-inducing abilities it is only natural that Kaposi's disease was also subjected to similar investigation.
During the early days of World War II efforts were made with Rous sarcoma to "cancerize" cells [10] and interest in the genetics of leukemia had developed [11]. By 1943, Rous sarcoma was grown in cell culture and its effects on cells were observed [12]. In a related study, Earle (1943) developed a strain of cancerous mouse cells, called 'L-cells", that would serve to advance the study of the leukemias [13]. Earle's malignant L-cells were developed using connective tissues (technically called "fibroblasts") of a strain of mice, called "C3H," which are prone to developing mammary cancer. Though Rous Sarcoma Virus (RSV) and the C3H-related Mouse Mammary Tumor Virus (MMTV) were not yet capable of being grown in human cells, the desire to move viruses associated with enzymatic activity and immunological deficiencies, i.e., leukemia/sarcoma and mammary malignancies, into the human species had taken a major step forward.
Investigation of metabolic processes occurring within sarcomatous cells continued [14] and the role of the thymus gland (which produces T-lymphocytes), spleen and gonads in the development of leukemia was outlined by McEndy, et al. (1944) [15]. Cottrell et al. (1944) described a syndrome of generalized lymphadenitis (inflammation of the lymph nodes) with neutrophil leukopenia (an abnormally small number of white blood cells formed in the bone marrow circulating in the blood) [16] and, though this constellation of symptoms has been identified in AIDS, whether a direct relationship to Cottrell's report exists cannot be specifically determined. Marcussen (1944) describes another constellation of symptoms also seen existing in AIDS, i.e., lymphadenopathy, skin changes, and blood abnormalities [17] but, again, whether Marcussen's observations are directly related to AIDS is unknown. Finally, Glendy et al. (1945) described yet another symptom also reported in AIDS; a case of primary atypical pneumonia of unknown cause with unusual complications [18]. Whether these several reports of AIDS-like symptoms bear any correlation with investigations of leukemia/sarcoma agents in the context of the Allies' World War II interest in developing biological weapons with the destructive power equivalent to the atomic bomb cannot be directly ascertained.
Another line of research developed during the 1930s that is also important to the present discussion. Neurotropic agents, i.e., central nervous system-attacking agents, were investigated which, along with the study of leukemia/sarcoma agents and mammary tumor viruses, helped to set in motion a scientific paradigm that remains extant even to the present day. In the early 1930s, Rivers et al. experimentally produced a myelin (a lipid membrane covering nerve cell axons) -destroying encephalomyelitis [encephalo = brain; myelitis = inflammation of the spinal cord or bone marrow] by injecting foreign brain tissue into the brains of monkeys [19]. Ferro and Jervis (1940) continued to refine methods for development of encephalopathy [20] employing techniques similar to Rivers and by 1943 neurotropic viruses had become valuable additions to the biological arsenal.
To detect presence of infection by neurotropic (i.e., central nervous system-attacking agents) viruses Havens et al. developed a complement-fixation test, i.e., complement testing consists of detecting virus antigen/host antibody reactions within a given individual [21]. An antigen is the virus's toxic protein which can cause illness; an antibody is manufactured by the infected host's immune system to attack the viral antigen. When a direct antigen/antibody bonding/match exists then a complement (an antigen/antibody pair) is fixed. A fixed complement shows presence of infection by a given virus type or its' close relative as well as what host antibody reacts to what virus type. Such a test allowed then, and allows today, characterization of numerous neurotropic agents based on their respective antigens.
Work on experimental encephalomyelitis continued and it was discovered that an autoimmune disorder could be created within subject animals [22]. Casals (1944) described immunological relationships among some central nervous system neurotropic viruses [23] and Lennette and Koprowski examined the effect of age on susceptibility to encephalopathic viruses [24]. By 1944 sufficient understanding of experimentally induced encephalitis had accrued to allow introductory investigations of immune reactions associated to encephalitis [25]. Thus, by 1944, investigation of leukemias/sarcomas, mammary tumor viruses, and encephalopathic viruses was well established.
The association of blood as a vector in transmission of encephalitis was strengthened by demonstrations of passage of encephalitic agents to mice by ticks [26]. Efforts to isolate other neurotropic viruses in the blood of infected hosts inevitably led investigators to Africa where malaria, itself a neurologic virus, was epidemic [27]. Search for more neurotropic agents commenced in Africa during the mid-1940s [28] and Kaposi's sarcoma in Africa was investigated [29]. Other investigations of diseases associated with Blacks occurred during the mid-1940s [30] and sexual behavior of Africans was of scientific interest [31].
Continuing efforts to find new neurotropic agents led to isolation of a number of herpes-related viruses from many sources. Notably, Blattner et al. (1944) recovered a virus from a case of Kaposi's varicelliform eruption [32]. Though varicelliform eruption is not Kaposi's sarcoma, varicelliform eruption was originally characterized by the same Dr. Kaposi associated with the sarcoma. Indicative that recovery of very exotic neurotropic agents was a priority during World War II, Casals and Webster (1944) reported the similarity of the virus causing "Russian Spring-Summer encephalitis" in man to the virus causing the disease "louping ill" in sheep [33]. Other studies of viruses of animals, particularly mice, as potential biological weapons against humans, showed progress.
Kutter (1934) had shown what appeared to be very similar viruses existing in humans, hamsters, white mice and wild rats [34]. This recognition of the similarity of viruses across species eventually became extremely important in study of cross-species virus infection and would, in the not distant future, facilitate infection of any species by any other specie's viruses. During the mid-1930s, Strong (1935) established a line of mice especially for the study of mammary tumors [35]. It is extremely interesting that HIV, the causative agent of AIDS, is now grouped in the category of retroviruses that can cause immunodeficiencies in which Mouse Mammary Tumor Virus (MMTV) is also a member. Strong's mouse mammary tumor cell line, called "C3H," (referred to earlier) was of special scientific interest during World War II and served as a parent cell line for development of various strains of mouse mammary cancer [36].
Following in Kutter's path, rat mammary cancer was investigated during the early years of World War II and found probably linked to a viral agent [37]. The significance of investigation of mammary tumor agents during World War II appears to generally complete the scientific paradigm associated with virus-based biological weapons development as it evolved during the War.
Specifically, the scientific paradigm, as it evolved during World War II, dictated that biological warfare-related research would focus on viral agents associated with leukemia/sarcoma, encephalomyelitis, and mammary carcinomas as an approach most likely to achieve the Allied powers' goal of developing a biological weapon with the destructive equivalent of the atomic bomb. In light of today's information concerning AIDS and historic investigations during World War II it is highly likely that development of an immunodeficiency-causing weapon was under consideration during World War II. Whether one or several were actually developed hinged on the ability to overcome the natural barrier of virus/species specificity.
Viral agents capable of directly attacking the body's immune system were not unknown during the years immediately preceding World War II. Traub (1935) isolated a virus capable of direct immunological attack on infected white mice [38]. This viral agent, called "lymphocytic choriomeningitis virus," (LCM), though not a retrovirus (it is called an "arenavirus"), later served as a valuable model for understanding viral-caused immunodeficiency. Particularly interesting and about which more will be later mentioned, LCM's effects are directed against thymus-derived lymphocytes, i.e., T-cells, of the infected mouse host. Also receiving scientific attention during World War II was a mouse encephalomyelitis-causing agent, called Theiler's GDVII virus, that appeared capable of cross-species infection of cotton rats and rhesus monkeys [39]. Theiler's virus resulted in paralysis in infected mice. As a result of 1940s scientific awareness of various immunologically active viral agents, existence of T-cell attacking model systems, and exploratory investigations to move viral agents across species' natural immunologic barriers, it is a logical conclusion that motivation to create a viral agent capable of causing immunodeficiency in humans has existed since at least World War II.
Whether the appearance of an acute immunodeficiency-causing leukoencephalitis appearing in Australia during the early 1940s in humans [40] is associated with these war-time-related scientific interests or is a natural infection is unknown but it is definitely the case that efforts to begin modification of biologic materials began [41]. The work of Avery et al. resulted in creation of the ability to "transform" biologic material. The process of transformation can essentially be explained as the insertion of foreign deoxyribonucleic acid (DNA) into an existing cell; the altered cell then takes on qualities and processes of the foreign DNA donor organism. In effect, a given species' cell is transformed into another species' cell. With the ability to transform cells established, a method of breaking down inter-species virus-specific barriers to allow cross-species infections was theoretically in place. Moreover, the insertion of foreign species' DNA into a host cell's DNA is not unlike the process used by retroviruses and, as we will see later, is associated with induction of malignancies in these host cells.
1946-1950
Though the "day that will live in infamy" was eclipsed by two that saw the vaporization of Hiroshima and Nagasaki, the end of World War II did not see the end of the scientific paradigm guiding development of biological weapons. Uneasy settlements at Yalta helped to give birth to the age of the "cold war" and reason for the continuance of the paradigm.
Horsfall and Curnen (1946) investigated a progressive pneumonia virus of mice that suggested more evidence for existence of cross-species viruses [42]. This mouse pneumonia virus appeared particularly interesting in its ability to manifest a latent infection, i.e., the virus could infect a host and leave the infected host symptom free even while the virus waged its attack. This observation, along with that seen in LCM where another latent infection existed, suggests latent/slow infections were becoming prominent in the biological warfare weapon's development scientific paradigm.
McCarty and Avery (1946) continued their investigation of the transformation of pneumoccocal pneumonia types [43] while investigation of immunological effects in experimentally induced auto-immune disorders in animals progressed [44]. Methods to speed development of immunologically-induced encephalomyelitis in rhesus monkeys were developed [45]. Of interest, Dennison and Evans (1946) reported a single case of Kaposi's occurring in a West African individual and considered the case noteworthy because of the infrequency of cases of Kaposi's disease isolated in the region [46].
Continued investigation of development of immunologically-induced disseminated encephalomyelitis led, in 1947, to use of brain tissue from other species, e.g., rabbits, to induce via injection, disease in rhesus monkeys [47]. Meanwhile, Gross (1947) investigated immunological relationships of several mammary cancer strains in female mice [48] that would serve as a foundation for his later (1951) discovery that leukemia could be induced in mice. Stern (1947), consistent with the existing scientific paradigm, investigated the nucleoprotein structure of genes [49]. Genetic predisposition to infection by various viral agents would become even more important in the future and would, particularly, involve investigation of humans.
In 1948, and in accord with previously isolated neurotropic and latent agents in animals, Heyl et al. (1948) conducted a survey of pools of gamma globulin (IgG), an important immuno-conferring protein produced in response to infection, in various sections of the United States [50]. Of particular interest to Heyl was detection of the presence of herpes simplex, LCM, and epidemic keratoconjunctivitis-associated infection in these human gamma globulin pools. Herpes simplex is a neurologic virus capable of residing in a hidden state within neural ganglion of infected individuals on a permanent basis; LCM infection can occasionally be passed to humans from Syrian hamsters and result in a temporary immunodeficiency disorder and can exist as a latent infection; epidemic keratoconjunctivitis, a rapidly developing inflammation of the mucous membrane of the eyeball and eyelid, is caused by an adenovirus (i.e., a DNA-based virus associated with the respiratory system, adenoids, and nasopharyngeal area of the body) family of viruses about which more will be presented later. Again, in keeping with the existing scientific paradigm, search in 1948 in human gammaglobulin for herpes simplex, LCM, and adenoviruses was a consistent venture. Precedent for search for respiratory-related agents was set through investigation of the progressive pneumonia virus of mice and transformation of pneumoccocal types by Avery.
Also occurring in 1948, Koprowski and Cox (1948) grew rabies virus in chicken embryos [51]. Though seemingly a rather elementary investigation several things were able to be established from results. First, rabies virus does not commonly infect chickens but was found capable of infecting chicken tissue if embryonic tissue was used. This finding helped establish a method of passing viruses across species by infecting embryonic tissue before species-specific immunologic barriers had time to develop and mature. Secondly, the investigation set the stage for continued study of the chicken tumor agent, Rous sarcoma, as a candidate for cross-species transfer. Again seen is yet another way to move viruses across species types. While study of the avian leukemia/sarcoma sub-paradigm moved forward, investigation of other virus agents and animal systems continued [52].
Warren et al. (1949) established a method to purify viruses which was necessary to both quantitative and qualitative investigation of viruses [53]. In 1950 studies of various mouse leukemias, both "spontaneously" occurring and radiation-induced, focused on T-cell and thymus gland-specific relationships to pathology [54]. Not to be outdone, investigators in the avian sub-paradigm characterized the stability of the Rous sarcoma virus under differing conditions [55] in preparation for later passage of Rous sarcoma to other species. Efforts to isolate still more encephalitis-causing viral agents continued though, now, with special reference to their genetic transmission [56].
A GENERAL OVERVIEW OF THE PERIOD
Clearly scientific interest in latent/persistent viruses has a long history dating back to the years immediately prior to and during World War II. On January 2, 1942, less than month after the United States entered the War, the first Washington, DC Conference concerning biological warfare was held [57]. Before six months had passed President Franklin D. Roosevelt, at the end of May 1942, gave his approval to create a biological warfare research organization which was subsequently supervised by George W. Merck, Director of the War Research Service. From 1942 onwards the Americans and the British shared their resources on biological warfare just as they did with many other weapons development projects [58].
Accelerated research on development of biological weapons began immediately after the start of World War II and was centered in the United States at Fort Detrick in Frederick, Maryland (now home of the National Cancer Institute) and in England at Porton Down. It was, as mentioned earlier, the intent of the biological warfare development division, costing millions of dollars and employing thousands of people, to ultimately give the Allies a weapon with the destructive power equivalent to the atomic bomb. During 1943 research activities escalated because of fear the Nazis would use biological weapons and, it is interesting to note, Dr. Theodore Rosebury, the civilian in charge of airborne infection projects at Fort Detrick, quit his position there in 1943 because of fear that biological warfare weapons produced in the facility would be disseminated. Former Congressman Richard D. McCarthy in his 1969 book The Ultimate Folly - War by Pestilence, Asphyxiation and Defoliation reported concerns expressed to Washington Post writer John Hanrahan by an "unidentified" Fort Detrick scientist stating:
"Another scientist..... echoed Dr. Rosebury's concern about the basic thinking behind the work at Detrick. He said he also was disturbed about the participation in the program of the Central Intelligence Agency." [59]
The interested reader is advised that a full 40,000 word report, written by Drs. Theodore Rosebury and Elvin Kabat, warning of the potentials for and problems of waging biological warfare was published in the Journal of Immunology during the last week of May, 1947.
By the summer of 1944, the Chemical Warfare Service, with support from the Army Surgeon General's Office, was involved in research on at least 25 different "problems" associated with biological warfare [60]. By the end of 1944 the Chemical Warfare Services had established four biological warfare-related institutions in the United States: a research and development site at Fort Detrick at Frederick, Maryland; a production plant at Vigo, near Terre Haute, Indiana; and two field-testing facilities--one at Horn Island, near Pascagoula, Mississippi, and the other at Granite Peak, Dugway, Utah. At its zenith, the Chemical Warfare Service employed 3,900 persons (2,800 Army, 1,000 Navy, and 100 civilians) in its biological warfare "Special Projects Division.' [61]
Suggestive of both the substantial progress in the three short years of intensive biological warfare research and development since 1942 and the concerns about that progress, Dr. Paul Fildes, in November 1945,
"dismissed the idea that a country could defend itself against biological attack merely by a program of research and vaccination: discovering the vaccines could take years, and a mass immunization program would be so obvious as to invite attack with a different disease." [62]
United States Navy Rear Admiral Harold W. Smith, Chief of the Research Division under Admiral Mclntire's Bureau of Medicine & Surgery, opined in 1946 that:
"biological warfare is such an uncontrollable weapon, offering hazards to the invader as well as the invaded, that it would be used by an enemy only as a weapon of desperation." [63]
It would appear obvious that the American/English biological warfare research community had thought out a strategy of development and use of diseases in war and investigation was focusing on the creation of latent viruses associated with leukemia/sarcoma, encephalitis, mammary cancer and respiratory agents that would resist quick vaccine solution. Perry Githens, editor of Popular Science in 1946, in remarks before a gathering of Philadelphia's Poor Richard Club describing biological warfare during May 1946,said,
"Begin by imagining a world in which there are only two preponderantly powerful countries . . . in a conflict of basic beliefs. Call it cold war or, hot peace, both nations feel the world isn't big enough for their opposing political ideologies. Now suppose a few men in one of these countries decide the other nation must be 'removed,' that it must be wiped out by a war without warfare. Supposing they plan a war without the formalities of overt acts, a kind of global sabotage aimed not at capture but at destruction, a truly ‘preventive war.' In this creeping war there would be no blitzkrieg, no declaration, no massing of forces.
The weapons for secret warfare exist. That I am competent to assure you . . . In a secret war the country under attack might wither as a nation, without knowing it had even been sick . . The amazing thing was how little it took to make the powerful industrial machine grind to a crawl. And this without a single atomic bomb. . ." [64]
During a House debate on US Naval appropriations in late May 1946, then Congressman Albert Thomas (D-TX) said relative to biological weapons,
"We have something far more deadly than the atomic bomb. We have it today -- not tomorrow -- and, furthermore, it's in usable shape." [65]
At this same debate then Congressman Harry Sheppard, chairman of the Naval Appropriations subcommittee, stated,
"This nation is in possession of scientific factors which place it in an enviable position. The scientific factors at hand would result in devastation equal to, if not greater than, the atomic bomb." [66]
Between 1943 and at least 1946 biological warfare research (by "Medical Research Unit No. I") was conducted at the University of California-Davis, under US Navy auspices. In 1946 it was reported that the Navy had a biological weapon which could wipe out "all forms of life" in a metropolitan area and that the weapon was "a germ proposition . . . sprayed from airplanes that can fly high enough to be reasonably safe from ground fire." [67] That the US Navy had a biological weapon potentially more destructive than the atomic bomb in 1946 is true but is eclipsed by the fact that Great Britain had gone even farther with its biological weapons' development then the US [68].
In the context of the present AIDS epidemic, a global disaster likely to kill at least a quarter to a third of the world's population, documentation that the United States and the Allied powers were, during World War II, actively investigating neurotropic, immunodeficiency-causing, vaccine development-resistant viruses with special emphasis on agents that are today considered directly related to HIV, e.g., Mouse Mammary Tumor Virus (MMTV) and leukemia/sarcoma, certainly indicates major incongruities may exist in the presently "accepted" explanation for the origins of AIDS. Did the AIDS virus arise naturally from some remote nowhere or did it originate from pursuit of the biological weapons' development paradigm? When will the American people become sufficiently curious about the origins of AIDS to move past "expert opinion" and seek their own answers in documented history? When will the really hard questions about the AIDS epidemic be addressed openly and honestly?
End of Chapter 1